Nylon Timing gears

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Model T Ford Forum: Forum 2016: Nylon Timing gears
Top of pagePrevious messageNext messageBottom of page Link to this message  By Dan Hatch on Monday, January 11, 2016 - 08:57 am:

Had an email this weekend about failing Nylon Timing gears. 3 out of 4 failed in a friend's cars. Teeth are cracking off. Anyone had the same problem? Dan


Top of pagePrevious messageNext messageBottom of page Link to this message  By Roger Karlsson, southern Sweden on Monday, January 11, 2016 - 10:30 am:

There have been a few occasional reports here about failed nylon gears, but many others have used them for many miles without problems. Guess it's a bit like the older fiber gears - many more have experienced trouble with them, but there are still a couple of very experienced T:ers that keeps on using the fiber gears for many many miles without trouble: Les Schubert and Dean Yoder.. Very careful fitting might be the key - and luck?

Here's a 2015 thread on nylon failures: http://www.mtfca.com/discus/messages/506218/534074.html?1429159905


Top of pagePrevious messageNext messageBottom of page Link to this message  By Steve Jelf, Parkerfield KS on Monday, January 11, 2016 - 10:45 am:

I have no experience with the Model T version, but my bad experience with a nylon timing gear in a Chebby makes me a disbeliever. I do have first-hand experience with a fiber Model T gear. Never again. I'll stick with a Ford or a McEachern gear. Oh, but those aren't as QUIET. Really? You can hear the timing gear over all the other noise a T makes? OK, enjoy how quiet it is after it goes to pieces.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ted Dumas on Monday, January 11, 2016 - 10:46 am:

It could be stresses from the manufacturing process:

http://www.plasticsintl.com/documents/NylonandReinforcedNylonAnnealing.pdf


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ken Todd, ............Red Deer, Alberta on Monday, January 11, 2016 - 11:29 am:

"failing Nylon Timing gears. 3 out of 4 failed in a friend's cars."

What condition were the mating gears in? If new nylon gears were run against previously used gears it stands to reason that they would fail prematurely.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Henry Petrino in Modesto, CA on Monday, January 11, 2016 - 01:05 pm:

That's funny Steve. You're 100% correct. When the timing gears let go the engine gets very quiet very suddenly. :-)


Top of pagePrevious messageNext messageBottom of page Link to this message  By Dan Hatch on Monday, January 11, 2016 - 01:10 pm:

Ken: New Babbitt, new gears, crank and gen. 3 engines out of 4 engines. Was told gear mesh was right. Has anyone else seen this. Dan


Top of pagePrevious messageNext messageBottom of page Link to this message  By Roger Karlsson, southern Sweden on Monday, January 11, 2016 - 01:10 pm:

I like Jim Rose's comment at the linked thread: "Model T's are supposed to be noisy and smell bad so the blind can hate them too" ;-)


Top of pagePrevious messageNext messageBottom of page Link to this message  By Roger Karlsson, southern Sweden on Monday, January 11, 2016 - 01:23 pm:

I haven't heard anybody have a failure with a Ford steel gear, neither with the available aluminium and bronze gears. Can't see any real need to look much further, but it's good there are options for the adventurous :-)


Top of pagePrevious messageNext messageBottom of page Link to this message  By Mark Gregush Portland Oregon on Monday, January 11, 2016 - 02:24 pm:

No issues so far. Few miles on crank gear before putting the cam gear on don't recall if gen gear was new or used. Didn't do anything special, just slapped that puppy together. Have run the engine for more then a few miles with it on, then ran for a while without it, now it's back on.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Brian Dowell on Monday, January 11, 2016 - 02:38 pm:

About a thousand miles after rebuild, During the last oil change little nylon pieces in oil. Teeth were shearing off the timing gear. This was last year at the MTFCI tour in Branson.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Constantine in Australia on Monday, January 11, 2016 - 02:42 pm:

Isn't a "quiet Model T" an oxymoron?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Dallas TX on Monday, January 11, 2016 - 02:50 pm:

Guess I need to look at mine again. Close to 5000 miles, in the '12. Have not noticed anything in the oil or the oil screen.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Constantine in Australia on Monday, January 11, 2016 - 03:00 pm:

I would never use a nylon gear...but if I was forced to I'd use only non-detergent non-synthetic motor oil. Why? How could anyone forget Russ Potter's research back in 2009 that concluded synthetic motor oil destroys babbitt...perhaps it also destroys nylon???


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Dallas TX on Monday, January 11, 2016 - 03:29 pm:

Constantine,

Anyone who concluded that motor oil - synthetic or not, detergent or not - destroys Babbitt is delusional.

I don't recall Russ Potter ever posting that here - where did this epiphany occur?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Tom Carnegie Spokane, WA on Monday, January 11, 2016 - 03:33 pm:

The last time I won the Montana 500, I was most surprised when my motor was torn down to find that my nylon timing gear was missing parts of several teeth and a few whole teeth. It did not effect how it ran at all, as far as I could tell. I chalked it up to the high-lift cam that I was running plus the fact that the gears that were being made at the time had the helix cut at the wrong angle. The newest gears that I have been getting, from a different source as the first, have the helix cut at the correct angle. So far we haven't had any trouble with these new gears out of dozens sold.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Kevin Whelihan Danbury, WI on Monday, January 11, 2016 - 03:37 pm:

I agree with Royce, if synthetic oil destroyed babbitt then every newer car on the road right now would have knocking connecting rods and low oil pressure. After 212K miles using synthetic oil in my '04 Escape, the oil pressure is right where it was the day I bought it.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Frank van Ekeren (Australia) on Monday, January 11, 2016 - 04:06 pm:

Bold statement Royce, do your research, synthetic oils are designed to overcome the problems of oxidation in mineral oils. Problems with oxidation for babbitt was a big problem in slow running bearings with high lead content, not so much in high tin babbitt.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jerry VanOoteghem - SE Michigan on Monday, January 11, 2016 - 04:09 pm:

Frank,

Had any babbitt destroyed by oil lately?

I don't think high lead babbitt for slow running bearings has anything to do with internal combustion engines or the oil used in them.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Constantine in Australia on Monday, January 11, 2016 - 04:27 pm:

Royce, the "Babbittgate" scandal (heh, heh) happened back in 2009, see these posts (you're in there too!) :

http://www.mtfca.com/discus/messages/80257/98647.html?1248057403

http://www.mtfca.com/discus/messages/80257/100671.html?1249441930


By rdupree on Monday, August 03, 2009 - 10:37 pm:

"I will share my 'first hand' experience in this matter. In about 2002 a friend of ours wanted to buy a nice Model T. At that time, one of our club members living in Kewanee, Illinois was wanting to sell the car his dad had owned. The story we were told is that Russ had rebuilt the engine, it had major problems, and was re-rebuilt by Russ. The seller had put maybe 2000 miles on the rebuilt engine. Our friends bought the car, and in less than 1000 miles had problems with the master clutch, which meant we needed to pull the engine. While the engine was apart, we decided to check the general condition of the bottom end. First, number 3 rod had excessive clearance, then we found that number 2 main was worn out as well. After some thought, we took the block, and fresh crank and rod cores to Tony Verschoore for a fresh rebuild. I knew that Russ had rebuilt the engine, so I took the bad rod to the Indy swap meet that fall to see if he could shed any light on the subject. His response was "I told the stupid ... not to use synthetic oil after the first time he ruined the engine". When we got the engine back from Tony, I tried to spend some time to insure that the fourth main was in proper alignment. I tried for a LONG time to get the tailshaft dialed into alignment, but could not get below about 0.020" tir or so UNTIL I put on a different flywheel. (This was the flywheel that had been on the car). The runout of the tailshaft immediately dropped to about 0.005" tir or less. We buttoned everything up, and the owner put 10,000 or more miles on the car in the next few years with no adjustments to the bottom end.

Did the use of synthetic oil during break-in cause the problems we saw? Or was the tailshaft alignment the problem?

Ron Dupree"

(Message edited by m2m on January 11, 2016)


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jay - In Northern California on Monday, January 11, 2016 - 04:45 pm:

Nylon? ........ We don't need no stinking Nylon!


Top of pagePrevious messageNext messageBottom of page Link to this message  By Frank van Ekeren (Australia) on Monday, January 11, 2016 - 05:21 pm:

No Jerry, but only this week I pulled down a T engine that was rebuilt in 2010, only run on test bench for 2 hrs and then left sitting, some clown had used lead babbitt rods, (bought from USA) and now all black from oxidation.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jay - In Northern California on Monday, January 11, 2016 - 05:26 pm:

Check out this link on babbitt
http://www.fordgarage.com/pages/babbittgrades.htm


Top of pagePrevious messageNext messageBottom of page Link to this message  By Les VonNordheim on Monday, January 11, 2016 - 05:33 pm:

Have the Nylon gears only failed in engines running gear driven generators or alternators? Very important question!

I have been using synthetic oil 10-30 in my model T for 15 years and NO bearing adjustments or failures.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Les Schubert on Monday, January 11, 2016 - 06:34 pm:

Like others I have been running synthetic oil for years now with no problems.
Gears. I have witnessed some TERRIBLE gear mesh fits over the years. I am "fastidious " about the gear mesh and am now approaching 40 years on one car and 15 on another one using fiber gears. Of course I also do my own line boring and space the crank to the cam at 3.937" (+or- .0002"). It is absolutely easy with right fixtures to do repeatedly!!


Top of pagePrevious messageNext messageBottom of page Link to this message  By Charlie B actually in Toms River N.J. on Monday, January 11, 2016 - 06:51 pm:

Oh hell, I'm not buying that excuse. Some one posted above: "has anyone's babbit been destroyed by oil lately"? It says it all doesn't it?


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Dewey, N. California on Monday, January 11, 2016 - 07:21 pm:

I wouldn't use nylon because it shrinks--proably the amount of shrinkage is related to the formula used to make it. I had an 85 Honda with power windows; had to replace the window motors because the nylon gears had shrunk and cracked as the metal centers didn't shrink! Of course, couldn't use junkyard motors, because their gears were also cracked! Based on that experience, I'd have to see some real good manufacturing and testing documentation on a Nylon timing gear before I'd even consider it.
This, of course, is just IMHO, and only worth what you are paying for it!
T'
David D.


Top of pagePrevious messageNext messageBottom of page Link to this message  By gene french on Monday, January 11, 2016 - 08:31 pm:

Dan:
regarding failed timing gears , either nylon or fiber (phenolic) ...i have observed numerous instances where the cam gear retaining nut was tightened using a cold chisel...the resulting impact from using a chisel to tighten the nut probably did a bunch to damage the bonding in the fiber type of gear ( assuming the gears were meshed together )...probably a similar effect on nylon tooth profiles ...just a guess ...always an optimist ...gene french


Top of pagePrevious messageNext messageBottom of page Link to this message  By Constantine in Australia on Monday, January 11, 2016 - 10:20 pm:

It's been mentioned before on this forum many times that fiber gears made in recent years are NOT of the same construction/quality as ones made decades ago...the ones Les Schubert and Dean Yoder are using. Fiber is likely to lead you to failure.

With nylon, many good reviews and many people love them, but like fiber there's just too many reported failures. Why are we not hearing report after report of bronze gears failing? Anyone?

Of course synthetic motor oil will not destroy your engine. The reason I brought up the famous Russ Potter "Babbittgate" scandal was to highlight something all too common in the T world. Namely, based on zero evidence and void of critical thinking people pluck ideas or theories out of the sky then peddle it out like it's a known fact.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Aaron Griffey, Hayward Ca. on Monday, January 11, 2016 - 10:56 pm:

Think gene French hit the nail on the head.
I once tightened the cam gear nut without holding the cam gear but just let the crankshaft hold it.
The car came back the next day with a bad knocking noise coming from the fiber cam gear.
A couple of the teeth were starting to break off.
I learned a lesson that time......stop and think before tightening the nut.
I bought an F1 pickup with a rebuilt engine in it.
I tore it down before using it just to see if it was done right.
All I found was the valves were too tight an I did not like the fiber timing gear.
Every now and then I try to listen for the metal gear noise.
I don't hear any.
I see no reason to use a non metal cam gear, unless it is to save money.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Aaron Griffey, Hayward Ca. on Monday, January 11, 2016 - 11:06 pm:

I wonder why synthetic oil doesn't eat the Babbitt off insert bearings in newer cars.?
Synthetic oil is far less likely to hurt any engine than mineral oil.


Top of pagePrevious messageNext messageBottom of page Link to this message  By gene french on Tuesday, January 12, 2016 - 09:44 am:

Aaron:
just for your interest ...i have made several "barrel vise" type holders to clamp the front cam journal into a bench vise ...this allows the camshaft to be held firmly without any force being applied to the gear teeth , then the cam gear retaining nut is tightened ...2 pieces of aluminum bar stock are bored to the journal diameter with a .010 to .015 shim between the 2 pieces of stock ...bore to actual journal diameter at the parting line ...remove the shims and you have a non-marring clamp that will hold against any reasonable tightening force needed ...always an optimist ...gene french


Top of pagePrevious messageNext messageBottom of page Link to this message  By George_Cherry Hill NJ on Tuesday, January 12, 2016 - 10:31 am:

Typically the nylon/nylatron gear running against a steel gear would require twice the cold clearance as a steel to steel/iron to steel arrangement. It's the physics of thermal growth differences between the alternate materials. Nylatron grows the most, so close clearance by choice at install becomes interference at temperature. Root radius failure point will almost always be caused by thermal growth causing the clearance to go negative regardless of materials.

Just Sayin' not preaching, draw your own conclusion and keep in mind that once the clearance goes to 0 the squish leads to additional localized heat that leads to even more thermal growth that leads to more interference, etc.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bill Robinson Salty Bottom, AL on Tuesday, January 12, 2016 - 11:32 am:

George- I like your explanation. It makes sense.

I think that I am probably the friend that Dan is referring to about having 3 failed nylon timing gears. On Dec 16, 2015 I posted some pictures on a thread about fiber timing gears. These pictures are of a failed nylon timing gear that lost 32 of the 64 teeth. http://www.mtfca.com/discus/messages/506218/595102.html?1450327895

The distance between the crankshaft and the camshaft measured 3.396. A machinist's specs should be 3.397. Plus or minus .002" is acceptable. Mine was within .001" of specs.

Gearlash: It was too late to measure the gear lash on the nylon gear- too far gone, but when the new gear was installed, lash measured within specs of between .004 & .006".

Car and nylon timing gear #2 had about the same results, except all teeth were intact (some were just hanging on one end, but were still on the gear. Again the distance between the crankshaft and the camshaft are within specs.

Car and nylon timing gear #3 (pictured below). Out of 64 teeth, 62 are cracked, the other 2 teeth were broken but recovered. Again the distance between the crankshaft and the camshaft are within specs.

Car #4 gear inspection will begin tomorrow, and I will report the findings at that time.

I am sure that some of you will find fault in something that was done wrong in the past installation of the nylon gears or in the installation of the new bronze gears. You always do. My intent here is to get your curiosity up and if your car or cars have the nylon gear, simply remove the generator and shine a flashlight upon the teeth for a simple inspection. Rotate the crank and inspect each and every tooth.



Zoomed in:


Top of pagePrevious messageNext messageBottom of page Link to this message  By Steve Jelf, Parkerfield KS on Tuesday, January 12, 2016 - 12:00 pm:

I've spun the crank with both hands for fifty years, and never had a kickback.

I've always used the stock pinion sleeve, and never had one fail.

I've driven thousands of miles with a nylon
[or fiber] timing gear and never had a failure.

Fine. Congratulations. But old sayings become old sayings because of the element of truth they contain, and the applicable old saying here is Where there's smoke there's fire. The fact that some, many, or most people don't experience a problem doesn't mean the problem doesn't exist. On the other hand, how many have broken an arm pulling up on the crank with the left hand? How many have had a FP pinion bearing fail? How many have had a bronze timing gear go south on them?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bill Robinson Salty Bottom, AL on Tuesday, January 12, 2016 - 12:19 pm:

Review this thread from last week on yearly mileage driven. Judging from the discussion, the average Model T owner drives from 20 to 300 miles per year. Some drive -0- miles.
http://www.mtfca.com/discus/messages/599638/602214.html?1452304317

A few drive 10,000 miles or more.

The forum members who drive on club tours drive 300-500 miles per tour.

Personally, My wife and I attend 4 to 5 tours per year, and I drive more at home than I do on tours.

The point is this- if you don't drive it- it won't break.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Les VonNordheim on Tuesday, January 12, 2016 - 12:39 pm:

Have Nylon timing gears only failed in engines running gear driven generators/altenators?

No one has addressed this question.

My interest in using an advanced Nylon timing gear is because I am using a Stipe 280 cam shaft. It's not a noise issue with me....I'm interested in better performance on hills.

Are off-set dowel pins available that would provide the same advance using a stock timing gear? I can re-drill a stock timing gear to provide the same advance.....just looking for an easier way to achieve the 1/2 tooth advance.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Scott Rosenthal in Cincinnati Oh on Tuesday, January 12, 2016 - 02:15 pm:

In addition to thermal instability, Nylon is hygroscopic. A block doesn't see standing water but is subject to atmospheric variation. Due to random thicknesses at various sections of the gear, a fair question is whether swelling occurs globally, or can the gear profile become distorted? Not the motor wizard, just asking the question.
Thx,
Scott


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jerry VanOoteghem - SE Michigan on Tuesday, January 12, 2016 - 04:30 pm:

Bill,

It looks to me like the helix angle on that gear was way off. One end of the teeth took all the load while the opposite ends look almost untouched. I used a gear that appears to be from the same manufacturing source as the one you have pictured. (The timing dot on mine was red.) I only ran it for one tour. It sound terrible but I didn't have a chance to remove it before the tour. There was no sign of teeth letting go, but I don't think it would have lasted long.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Dan Treace, North FL on Tuesday, January 12, 2016 - 05:20 pm:

Well hope not...ugh.

Just got this '23 rebuilt shortblock, will be a while before assembly and use.

But had the builder use the advanced plastic gear,
{Lang's p/n 3047NYLA} which is claimed to be special hard plastic nylon, resistant to high temp, on a Chaffins regrind touring cam.

Thought why not, to see if the advanced timing gear would be a performance improvement?

Wonder if stripped teeth are in the future :-(







Top of pagePrevious messageNext messageBottom of page Link to this message  By Les Schubert on Tuesday, January 12, 2016 - 06:25 pm:

Bill
Do you have a generator? How is the gear lash on it? There is a reason that shim gaskets are available for the generator bracket.
What you running for cam shaft?
Any other accessories driven by the gears (oil pumps etc)?
How did you tighten the gear? With the cam out of the engine, or by holding against the crank gear?
I'm just trying to make sure I understand all the facts
Further to people talking about nylon with integral steel hub style gear failures. I have fixed some number of these on 40 year old Pfaff sewing machines. I don't believe this will be applicable to this application as there is no integral steel hub


Top of pagePrevious messageNext messageBottom of page Link to this message  By Norman T. Kling on Tuesday, January 12, 2016 - 06:56 pm:

I have not used nylon, but have seen what happens to fiber gears. The nylon might work out just fine if mated with good crankshaft and generator gears. Also end play of either or both camshaft and crankshaft can cause problems.

This is what I think happens. A used steel gear will be worn and especially if the gears are out of alignment will have a sharp edge on it. This sharper edge will quickly cut into the nylon or fiber causing it to fail.

Anyway, I personally use aluminum gears.
Norm


Top of pagePrevious messageNext messageBottom of page Link to this message  By Dan Killecut on Tuesday, January 12, 2016 - 07:24 pm:

I think the picture that Dan posted of the timing gear that he bought from Langs is the one that is made by White's machine shop. I have one on my 14 that I have put over 10,000 miles on. I had the opportunity to take the engine apart last summer, looking for an errant piece of safety wire. The timing gear didn't have any appreciable wear on it. Still looked good. When I installed it I wasn't sure I trusted it, so I carry an NOS Ford gear under the seat. So far so good.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bill Robinson Salty Bottom, AL on Tuesday, January 12, 2016 - 08:17 pm:

Les Schubert- answers to your questions:
* Do you have a generator? Yes
* How is the gear lash on it? As stated earlier- Gearlash: It was too late to measure the gear lash on the nylon gear- too far gone, but when the new gear was installed, lash measured within specs of between .004 & .006".
* What you running for cam shaft? 2 engines had the Stipe 280, one engine had the Stipe 250.
* Any other accessories driven by the gears (oil pumps etc)? No
* How did you tighten the gear? With the cam out of the engine, or by holding against the crank gear? by holding against the crank gear but no hammering?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Les Schubert on Tuesday, January 12, 2016 - 11:44 pm:

Bill
Was that also the gear lash of the generator gear?
Thx


Top of pagePrevious messageNext messageBottom of page Link to this message  By Eric Sole - Castelldefels (Spain) on Wednesday, January 13, 2016 - 08:41 am:

I meant to add this comment to the 2015 thread about the fiber cam gears but cannot write there. I'll go ahead and post it here as it is related.

The fiber cam gear I installed in 1988 worked OK (I don't drive a lot of miles) but with the engine torn down I could here a "cliquety clok sound for every two turns of the crankshaft with the rods and valves out.

After removing the cam gear I found a couple small bits missing which are marked in attached picture. Some other teeth were slightly swollen and others had hard "deposits" sticking out of them. Hard to know which were the real culprits.

I have a new aluminum cam gear and new steel gears for the crank and generator ready to go in when I reassemble.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Eric Sole - Castelldefels (Spain) on Wednesday, January 13, 2016 - 09:11 am:

Now for questions I cannot find the answers to in the Shop Manual or the MTFCA engine book...

Is it best to tighten the cam gear before installing the camshaft in the block?

Where do you hold the camshaft while tightening the nut?

How tight should the nut be on an aluminum gear? I have the socket tool.

Does the nut need Locktite? I think I saw this suggested elsewhere on the Forum.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Les Schubert on Wednesday, January 13, 2016 - 11:03 am:

Potential cause of your "issue". Some large "particles" were accidentally ingested through the oil filler.
I wonder now if that has not contributed to some of the fiber gear failures?
Nut. I have grabbed the cam with aluminum jaw covers vertically in my vice


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ted Dumas on Wednesday, January 13, 2016 - 11:06 am:

Tighten the cam nut after the cam is in the engine. Use a breaker bar about 12" long to tighten the nut. It does not need to be tightened like a rear axle nut. Don't use Loctite, you might want to get off some day without a hassle. Just tighten the nut, I use a 1-1/8 combination wrench with a home made offset to fit the nut.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ken Todd, ............Red Deer, Alberta on Wednesday, January 13, 2016 - 11:48 am:

FWIW, a Model A spark plug wrench works just fine for tightening the camshaft nut on a T. The right size and the correct offset.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Eric Sole - Castelldefels (Spain) on Thursday, January 14, 2016 - 05:14 am:

OK guys, thanks for your suggestions.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Peter B. Ratledge on Thursday, January 14, 2016 - 09:22 pm:

Gentleman,
In my 1911 T,I installed a Stipe 280 Cam and a Nylon timing gear around 20 years ago. I have had no problem to date.
I use 15-40 Napa fleet oil. It is API/SL rated.
It still has the zink in it. I have a screen in my hogs head. I have seen no Nylon fibers as of yet.

In my 1923 I used a fiber gear and it did not last and the metal gear was to noisey.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Kohnke Rebabbitting, Clare, Iowa on Thursday, January 14, 2016 - 11:41 pm:

Top of pagePrevious messageNext messageBottom of page Link to this message By Frank van Ekeren (Australia) on Monday, January 11, 2016 - 05:21 pm:
No Jerry, but only this week I pulled down a T engine that was rebuilt in 2010, only run on test bench for 2 hrs and then left sitting, some clown had used lead babbitt rods, (bought from USA) and now all black from oxidation."END QUOTE"

Frank, lead Babbitt in rods, Mains or Main shells, cam bearings, ect., will turn dark, just laying out in the open on a shop bench, it starts oxidizing right after machining.

That's what it does, nothing new.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Frank van Ekeren (Australia) on Friday, January 15, 2016 - 12:51 am:

That's right Herm, nothing new,
but your over looking the point, oils have had additives to try and combat oxidation and corrosion for how long? The point is that organic acids and electrolytes attacks lead in bearings.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Dan McEachern on Friday, January 15, 2016 - 01:01 am:

Do what you feel works for you, tighten the cam gear nut in the engine or when the cam is out of the engine, but I strongly suggest that you DO NOT use the gear teeth to prevent cam rotation during the nut tightening process- regardless of what kind of material the cam gear is made out of.
Clamp on the exhaust lobe using soft material to protect the lobe surface, or clamp on the rim of the gear if the cam is out of the block. In a late block you can remove the generator bracket and clamp a bar on the rim of the gear to prevent rotation. On an early block, obviously this cannot be done. Point I'm trying to make is that gear teeth can be damaged pretty easily.


Top of pagePrevious messageNext messageBottom of page Link to this message  By John Noonan - Norton, MA. on Friday, January 15, 2016 - 01:12 am:

Threads like this, in my opinion is what makes this forum so great. Lots of input from owners of fiber/nylon gears who love them V.S those who have had them and hate them. I personally just removed one from an engine not because it was failing, but because i had it apart and knew i had a better option. I realize cost is sometimes a factor when you make decisions about matters like this, but what is the cost differential between a plastic/nylon $65.00 gear, and an Aluminum or Bronze gear made by vendors we should support?


Top of pagePrevious messageNext messageBottom of page Link to this message  By John Noonan - Norton, MA. on Friday, January 15, 2016 - 01:24 am:

Well, that was some weird timing...Love your gears Dan.:-)


Top of pagePrevious messageNext messageBottom of page Link to this message  By Les VonNordheim on Friday, January 15, 2016 - 01:30 am:

Allowing several teeth of a Nylon or Fiber gear to support the torque of tightening the cam nut may be the major cause for non metal timing gear failure. Thank you all for sharing your findings. At least now, I know some of the risks involved using an advance Nylon timing gear. At this point, I plan on still using the new Nylon advanced timing gear I purchased for my new build 1913 engine using a Stipe 280 camshaft and Scat crankshaft.


Top of pagePrevious messageNext messageBottom of page Link to this message  By John Doolittle on Friday, January 15, 2016 - 07:01 am:

My credentials- a self-taught shade tree mechanic with over 50 years experience. I would venture to guess that most readers of the forum and Model T hobbyists have similar credentials, depending on age, naturally.

Many of the respected posters on this forum are school trained professional mechanics and/or machinists and us shade tree guys are lucky to to have their experience to guide us. They direct us- we read and follow their instructions. We have nowhere else to go for information.

Why is it:
that previous discussions about cam nut torque on this forum is so wide ranged, and the dangers of excessive torque can damage the camshaft, yet don't mention the teeth of the gear? Example: http://www.mtfca.com/discus/messages/29/45025.html?1200065550

Then why is it:
that if timing gears are so weak that if we torque the cam nut without somehow clamping the cam gear to prevent undue pressure on the teeth is just now coming to light?

Why is it:
that the manufacturers of the gears do not include specific instructions for installation of their products? Maybe the problems that Model T owners have had in the past with the fiber and nylon gears would have been eliminated had we been aware that tightening the cam nut would have caused damage to their product.

Why is it:
that a manufacturer would spend so much time designing, building, and marketing the product, yet not spend a few minutes writing a set of installation instructions? Then, when the product fails, the blame is put on us shade tree guys who write about crappy products on the forum, which eventually leads to the death of all their good work?

Why is it:
that the some say fiber, bronze, and nylon timing gears should not be used on engines that run a generator? The vendors don't warn against such usage. The product manufacturers don't warn against it.


Top of pagePrevious messageNext messageBottom of page Link to this message  By John Zibell, Huntsville, AL on Friday, January 15, 2016 - 11:19 am:

"Dan McEachern on Friday, January 15, 2016 - 01:01 am:

Do what you feel works for you, tighten the cam gear nut in the engine or when the cam is out of the engine, but I strongly suggest that you DO NOT use the gear teeth to prevent cam rotation during the nut tightening process- regardless of what kind of material the cam gear is made out of.
Clamp on the exhaust lobe using soft material to protect the lobe surface, or clamp on the rim of the gear if the cam is out of the block. In a late block you can remove the generator bracket and clamp a bar on the rim of the gear to prevent rotation. On an early block, obviously this cannot be done. Point I'm trying to make is that gear teeth can be damaged pretty easily."

All well and good. So how do you propose to tighten the timer flapper/roller nut on an assembled engine? What choice is there?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bill Robinson Salty Bottom, AL on Friday, January 15, 2016 - 03:02 pm:

Nylon timing gear #4 has been removed and appears to be fine. No cracks. 1 out of 4 is not bad.

The first person to send me a PM can have it for the price of the postage. USA only, please.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Dallas TX on Friday, January 15, 2016 - 03:14 pm:

Aluminum is $53.50 - see here:

https://www.modeltford.com/model-t-parts/engine/timing-gear/


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bill Robinson Salty Bottom, AL on Friday, January 15, 2016 - 08:47 pm:

The timing gear has been promised.
Bill


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jerry VanOoteghem - SE Michigan on Friday, January 15, 2016 - 11:13 pm:

John Z.

The roller/flapper nut needs such little torque it would never be a problem.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Constantine in Australia on Saturday, January 16, 2016 - 03:11 am:

I've heard from people in the know that not all the currently available metal gears are of the same quality. Buy one of Dan's gears is my advice.


Top of pagePrevious messageNext messageBottom of page Link to this message  By John Zibell, Huntsville, AL on Saturday, January 16, 2016 - 10:08 am:

"Jerry VanOoteghem - SE Michigan on Friday, January 15, 2016 - 11:13 pm:

John Z.

The roller/flapper nut needs such little torque it would never be a problem."


In that case, how much torque does the cam nut require? No torque values are given for any fastener on the T. Does the cam nut need to be so tight that you would damage the gears? Also the flapper being tightened will also prevent the cam nut from backing off. I'm not a ham fisted guy and do my tightening on a T by feel using experience from working on other machines.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Dallas TX on Saturday, January 16, 2016 - 10:43 am:

A Model A spark plug wrench does not fit the timing gear nut on a Model T. Too small.

Many of us have modified Model A spark plug wrenches to do this task. It is a relatively easy task using a band saw and then file to fit. The offset is ideal.

I have always tightened the nut with the engine fully assembled. This should not cause any damage to anything. Never has in my experience.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ken Todd, ............Red Deer, Alberta on Saturday, January 16, 2016 - 10:49 am:

"A Model A spark plug wrench does not fit the timing gear nut on a Model T. Too small."

Royce, maybe the US made Model A spark plug wrench is different than a Canadian made one?
I've used a Canadian Model A spark plug wrench on T camshaft nuts numerous times and it fits perfectly.

Going to the shop later today and will measure the A wrench AF and see what it is, will also measure a spare T camshaft nut that I have.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Dallas TX on Saturday, January 16, 2016 - 11:26 am:

Ken,

Right you are, I was thinking of the method to modify a T spark plug wrench to do this job. I walked out to the shop and compared a Model A plug wrench (actually two of them) to the Ford 5Z factory cam nut wrench (lower wrench in the photo below). All are the same size and fit a Model A spark plug as well as a Model T cam gear nut.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ken Todd, ............Red Deer, Alberta on Saturday, January 16, 2016 - 08:37 pm:

Ah, you saw the light.
The T camshaft nut is 1-1/8" AF, the same as the original spark plugs in a Model A. Modern spark plugs for an A are 7/8", the same as T plugs and a T wrench fits them also.
Here's an A plug wrench w/a T camshaft nut"


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ken Todd, ............Red Deer, Alberta on Tuesday, January 19, 2016 - 10:28 am:

"Modern spark plugs for an A are 7/8" "

I made a mistake, that should be 15/16", not 7/8".


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jerry VanOoteghem - SE Michigan on Tuesday, January 19, 2016 - 10:47 am:

John Z.,

The rotor nut does not help to lock the timing gear nut. Each mounts on it's own diameter with its own distinct nut.

While I agree that tightening against the timing gear teeth can be bad, I'll state here that I've always done it. How much torque? I don't know, but not especially tight. I've tightened the nut with even, constant pressure, being careful not to "bounce" on the wrench or give it any intermittent "heave ho's" to get that last bit of tightness. It's a fine thread and will get tight with reasonably light torque. Never had any trouble that I know of, but have had 3 fiber timing gears fail after 2 or 3 years of service. In my thinking, I can't relate those failures with a nut tightening some 3 years previous. Again, "in my thinking".

You asked, "Does the cam nut need to be so tight that you would damage the gears?" The answer is: No.


Top of pagePrevious messageNext messageBottom of page Link to this message  By John Zibell, Huntsville, AL on Tuesday, January 19, 2016 - 10:45 pm:

Jerry, when you install a nylon gear, you have to use a shorter cam nut or there isn't room to mount the flapper/roller. To me, this indicates it butts up against the cam nut. If the nut to hold the timer part is tight enough that is doesn't back off, neither will the cam nut.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jerry VanOoteghem - SE Michigan on Wednesday, January 20, 2016 - 01:18 pm:

John,

Not sayin' I can't be wrong, but...


Top of pagePrevious messageNext messageBottom of page Link to this message  By Dan Treace, North FL on Thursday, January 21, 2016 - 08:56 pm:

John

That's correct, or at least what the pkg. insert on the Nylon 6 plastic gear says. The plastic timing gear is thicker in the center than the metal gear, so a special thin cam nut is supplied, or you grind down a stock cam nut.


Top of pagePrevious messageNext messageBottom of page Link to this message  By John Zibell, Huntsville, AL on Thursday, January 21, 2016 - 10:31 pm:

Jerry, Dan, Yes and no on that. I have mine apart to put in a Bronze gear and checked the fitment this afternoon. It just so happens that the cam nut is flush with the cam nose that Jerry pointed out above. However, the roller base isn't thick enough to butt against the cam nut, just the cam face that Jerry pointed out. It appears the different size cam nuts are needed to allow the roller to seat properly and align with the timer contacts. If the roller base were thicker, it would contact the cam nut, but the way rollers are made, they don't.


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