Think I found the problem

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Model T Ford Forum: Forum 2013: Think I found the problem
Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Dallas TX on Sunday, August 11, 2013 - 03:31 pm:

In the "What have you done on your T today" thread I mentioned that I was pulling the engine from my '12 because it had an odd noise / vibration that was happening at progressively lower speeds over time. Initially it only made the noise at speeds above 35 MPH. In the past month the noise started happening at 30 MPH. After trying a lot of troubleshooting that didn't reveal anything, I pulled the engine, removed the hogshead, and the pan.

Turns out three of the brass screws holding the magnet keepers were no longer tight. The keepers were ever so slightly hitting the coil center poles as the engine reached higher speeds. There were scuff marks on 4 of the coil poles.

This was a new set of screws, tightened with a screwdriver socket tip, and peened over. Yet now they are loose! I am going to replace all the screws and use Loctite, along with peening this time.






Top of pagePrevious messageNext messageBottom of page Link to this message  By Harold Schwendeman - Sumner,WA on Sunday, August 11, 2013 - 04:22 pm:

Great pictures Royce; thanks for documenting this experience with pictures and explanations, as I'm sure this will be a learning experience for all of us.

I'm betting that there are many who would love to tell you that this would not have happened if you'd have had a distributor ignition system instead of all those little parts that could come loose from the flywheel, so......I'll say it! Ha, ha,....just pull'n yer chain Royce!

Seriously though, I appreciate Model "T's with the original ignitions systems as much as anyone, and I couldn't agree more with what you always say Royce, about how reliable and trouble free the original low tension magneto systems is, but then maybe that should be more properly worded,...."how reliable and trouble free the original system WAS"! I say that because the difference nowadays is that those old parts are approaching 100 years old, and many replacement parts just are not of the same quality of the originals.

As I said, I was just kidding you a bit Royce, but I sincerely hope that this great thread you've started does NOT turn into one of those threads full of arguments, insults, name-calling, or the too common Jablonsky/Peterson "debates"!

With your (and your Dad's) experience and knowledge Royce, I hope you can make a thorough "study" of what has happened here Royce, and WHY, and how such a failure can be avoided by the rest of us in the future. In other words, were the loose screws because they were inferior quality replacement screws as opposed to ORIGINAL, or were they 100 year old originals that failed from fatigue, or what???

Please guys,......respect the fact that Royce is open-minded enough to share with us an unfortunate experience with a system that he has praised to the utmost in the past, and I for one think he should be respected for his sincerity in making it a learning experience that will no doubt benefit us all. Let my bit of "kidding" Royce be an example of how to respect a guy for having "balls" enough to share this with us, even tho' he could be opening the door, so to speak, for further insults and such. We're all adults, so let's act like it,......thanks,......harold


Top of pagePrevious messageNext messageBottom of page Link to this message  By Harold Schwendeman - Sumner,WA on Sunday, August 11, 2013 - 04:26 pm:

Well shucks! In re-reading Royces post, he DID say that they were new screws! Gotta' read more carefully, right? Still, I can't help but think that a lot can be learned here!


Top of pagePrevious messageNext messageBottom of page Link to this message  By Harold Schwendeman - Sumner,WA on Sunday, August 11, 2013 - 04:42 pm:

Okay, I did read MORE CAREFULLY, and let me throw this one out for consideration:

Royce, you said that the keepers started hitting as the engine reached higher speeds. So, do you suppose that that was because at higher speeds (rpm) the magneto puts out more voltage, which makes the magnetic attraction stronger, which causes the slight deflection of the coil ring to increase, which then causes the keepers to contact the coil center poles?

If so, is that what made the screws begin to loosen? Maybe the screws were not at fault at all, and perhaps the answer is to do something to reduce the deflection of the coil ring,...??? Or, maybe the "gap" should be set a bit more to the acceptable upper limit??? Was the coil ring an original that was fatigued, or a "repop" that was of inferior quality?

Yeah,.....I think a lot will be learned here if this failure is properly analyzed, and maybe we're lucky in that respect in that it happened to a guy that's a Model "T" savvy as Royce & his dad,.......harold


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bob Cascisa - Poulsbo, Washington on Sunday, August 11, 2013 - 04:52 pm:

Royce,

Try a Brace & bit to tighten the screws. It is much easier to hold a downward force while applying a rotational torque.

Be_Zero_Be


Top of pagePrevious messageNext messageBottom of page Link to this message  By Craig Anderson, central Wisconsin on Sunday, August 11, 2013 - 05:03 pm:

I cannot highly enough recommend Wicking Loctite 290 (sold by Carquest as "Thread Locker") >>> http://www.loctiteproducts.com/p/t_lkr_green/overview/Loctite-Threadlocker-Green -290.htm

I have used this stuff for years, not only for locking threaded fasteners after they have been tightened but also for sealing possible minute cracks in welded areas that could leak.
I've used in small cracks too with 100% success.
It has never failed me and I wouldn't be without it.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ken Kopsky, Lytle TX on Sunday, August 11, 2013 - 05:08 pm:

Perhaps hitting the magnet cores is what loosened the screws. A peened screw won't back out on its own. Too late the check clearance now but I would pay particular attention to the crank end play and the magnet gap.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Hal Davis-SE Georgia on Sunday, August 11, 2013 - 05:12 pm:

Glad you caught it before it ruined a coil ring!


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Dallas TX on Sunday, August 11, 2013 - 05:25 pm:

Bob,

I used a 3/8" drive ratchet socket that has a screwdriver tip on the end. It allows me to lean on the ratchet while tightening the screws.

Craig,

Green Loctite was exactly what I was thinking of too.

Ken,

You might be on to something. The loose screws are a bit bent. One of the faults of 1912 and earlier magnetos is the stamped steel coil ring support. It flexes easily. I would have thought that the bottom, unsupported areas would be drawn towards the magnets as speed of the engine increased. Oddly though it was touching only at the coils near RH top from 1:00 to 3:00. I had the coil ring set at.025" gap, maybe .035" is a better plan going forward.

I have decided to install a later (1919 - 27 style) coil ring. The cast iron frame is stouter. Ford probably made this part beefier for good reason. Also the oval shape of the coils gives more leeway to the position of the spark lever while driving. The round coils are much more demanding of precise adjustment of the spark lever for best performance.

The mileage from the engine overhaul is 11,035. Russ Furstnow coincidentally restored the speedometer while I had the engine out. As you can see Russ does better work than I do!!!!!! The speedometer has always worked flawlessly.


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Sosnoski on Sunday, August 11, 2013 - 05:52 pm:

If you change to a later coil ring, you will also have to change the magnets. There are several different thicknesses of magnets. You can't just change the coil ring or you will never even be close to setting the magnet heights.

I don't remember offhand what all the variations are, but there is a chart in Lang's catalog which gives all that info.

Dave S.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Dallas TX on Sunday, August 11, 2013 - 05:59 pm:

Dave,

No problem, I have all that in stock. Appreciate the heads up, I need to start making a list.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Dave Young in Mays Landing, NJ on Sunday, August 11, 2013 - 07:13 pm:

Royce,
Are you familiar with, and do you like, the method of balancing the transmission assembly by moving the magnets in or out along their clamps? This was done by my rebuilder a few years ago. I was unfamiliar with the technique but it makes sense.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Stephen D Heatherly on Sunday, August 11, 2013 - 07:37 pm:

Royce, I'm glad you found the problem. I knew those earlier oil line funnels were smaller but, not that small!

Stephen


Top of pagePrevious messageNext messageBottom of page Link to this message  By Hap Tucker in Sumter SC on Sunday, August 11, 2013 - 09:03 pm:

Royce,

I’m so glad you found the problem before it became a major issue. A good example of why it is important to check noises rather than just hoping they will go away.

Good luck and please keep us posted on the progress

Respectfully submitted,

Hap l9l5 cut off


Top of pagePrevious messageNext messageBottom of page Link to this message  By A. Gustaf Bryngelson on Sunday, August 11, 2013 - 09:52 pm:

Hap,
One of the problems with a T is it does not have a radio to turn up when you hear a different noise.
Best
Gus


Top of pagePrevious messageNext messageBottom of page Link to this message  By Larry Smith on Sunday, August 11, 2013 - 10:01 pm:

I had a similar problem with my '13 touring, but the whole screw broke, and boy did it make a noise. I haven't pulled the engine yet, but I know that's what it is.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Paul Mikeska, Denver CO on Monday, August 12, 2013 - 12:41 am:

I could be way off base but I seem to remember that there was some discussion on this forum several years ago that there were some reproduction brass magnet screws that were way to soft. If so they could stretch after proper initial tightening when you add some heavy duty cycles.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Simon Bayley on Monday, August 12, 2013 - 06:50 am:

Royce,

Good article - thanks for sharing.

Are they 5/8th magnets you were running on your original setup?
Regards Simon


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Dallas TX on Monday, August 12, 2013 - 07:53 am:

Simon,

Yes, the magnets are 5/8".

I've reconsidered since last night. This car is largely intact, with nearly all the components it came down the assembly line with in 1912. This coil ring and magnet set has been on the car for 100 years. The transmission still has the date stamp on it from when it was assembled.

I need to turn up my game and make it work. Substituting more sophisticated stuff doesn't improve the car. It cheapens it. I may have to fool with this a little more, but it is going to be a better car with the original stuff intact when I get done.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Norman T. Kling on Monday, August 12, 2013 - 11:05 am:

You probably know this, but just in case you don't or someone else who sees this post is not aware of it, I will post the following.

When you install a magneto, the engine should be on a stand which allows the crankshaft to move all the way forward. It should be turned nose down and not supported by the crankshaft so that the crankshaft will move as close to the coils as the rear main will allow. Then measure the clearance at each coil post. Rotate the crankshaft and measure all the way around. Do this in several positions, in fact the best would be to measure each magnet pole to each coil pole. No clearance should be less than .0025. The ones at the bottom of the coils should be a little farther than those at the top so that the magnetic pull or sag in the transmission will not allow the poles to scrape.

In mho it looks from your picture that two of the magnet poles were too close to the coil posts.
Norm


Top of pagePrevious messageNext messageBottom of page Link to this message  By Scott Conger on Monday, August 12, 2013 - 11:08 am:

Norm

I think you meant 0.025"


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Dewey, N. California on Monday, August 12, 2013 - 12:06 pm:

Royce,
Good decision--if the car weren't so original, it probably wouldn't matter as much. I think you're making the right move!
But, what do I know?
T'
David


Top of pagePrevious messageNext messageBottom of page Link to this message  By Richard Gould on Monday, August 12, 2013 - 01:04 pm:

Speaking of originality, I'd consider swapping the flywheel for 1911-1912 vintage. I think the magnet bolts should also be safety wired. Ford didn't eliminate the wire until much later in production. The mag coil looks to be recently rebuilt. I've never seen an original that looked like that. Looks like the firewall is original too, darn good shape if it is.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jerry VanOoteghem on Monday, August 12, 2013 - 01:39 pm:

Royce,

You state that the plates are rubbing on only the poles in the 1:00 - 3:00 positions. If it were only a loose plate issue and your coil ring was lined up good, the plates should have contacted somewhat evenly all around your ring. I'm thinking it was a coil ring flexure issue that loosened some of your plates. Obviously some of the slightly higher ones.

Let us know the final verdict.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Harold Schwendeman - Sumner,WA on Monday, August 12, 2013 - 02:23 pm:

Royce - I guess it's pretty common knowledge that the bottom half of the stamped coil support ring flexes a bit due to the "pull" of the magnets, but I wonder if the top half of the coil support ring can actually flex a bit too, considering that the four points where it is fastened is on a pretty small diameter bolt circle. Especially when it's as you say, the earlier and lighter made stamping and nearly a hundred years old. Probably no question that the four bolts (or nuts) were tight as they are (were) safety wired, but perhaps after all those years of magnetic "pull", a bit of metal fatigue in the metal stamping in the area of each of the four fastening points....???

Knowing your usual "thoroughness", did you note how much crankshaft end play was present prior to disassembly? Certainly any end play at all (and there's always some) would have been a factor, right? I'm thinking this might be one of those cases where a couple thousandths here and a couple more there, etc, etc, might have added up to just enough to cause the problem,....just sorta' think'n out loud,......harold


Top of pagePrevious messageNext messageBottom of page Link to this message  By Harold Schwendeman - Sumner,WA on Monday, August 12, 2013 - 02:35 pm:

Royce - I guess it's pretty common knowledge that the bottom half of the stamped coil support ring flexes a bit due to the "pull" of the magnets, but I wonder if the top half of the coil support ring can actually flex a bit too, considering that the four points where it is fastened is on a pretty small diameter bolt circle. Especially when it's as you say, the earlier and lighter made stamping and nearly a hundred years old. Probably no question that the four bolts (or nuts) were tight as they are (were) safety wired, but perhaps after all those years of magnetic "pull", a bit of metal fatigue in the metal stamping in the area of each of the four fastening points....???

Knowing your usual "thoroughness", did you note how much crankshaft end play was present prior to disassembly? Certainly any end play at all (and there's always some) would have been a factor, right? I'm thinking this might be one of those cases where a couple thousandths here and a couple more there, etc, etc, might have added up to just enough to cause the problem,....just sorta' think'n out loud,......harold


Top of pagePrevious messageNext messageBottom of page Link to this message  By Harold Schwendeman - Sumner,WA on Monday, August 12, 2013 - 02:37 pm:

Dang it! Did it again! Got a phone call right in the middle of posting and kinda' lost track of where I was at! Sorry....harold


Top of pagePrevious messageNext messageBottom of page Link to this message  By Garnet on Monday, August 12, 2013 - 04:15 pm:

Just open the same message thread in a new window Harold to see if you had posted the message or not. I do this frequently when I get the odd error message when posting. I go check first before attempting to post again just to make sure I don't double up.

Regards,
Garnet


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Dallas TX on Monday, August 12, 2013 - 07:51 pm:

Richard -

Firewall was replaced by some previous owner. It's marine plywood with a lot of misdrilled holes due to people hanging tour placques, master vibrators, clocks, various speedometers, switches, and who knows what over the years. It looks great at 20 feet.

I rebuilt the engine because the original Dodge Brothers crankshaft broke. While the engine was out I sent the original coil ring to Wally Szumuski with death threats if I didn't get the same one back that was native to my car. I pulled off the magnets and checked for cracks, which necessitated replacing the screws. I used a KRW magnet tool to make them all the same height, which they pretty much were already. A couple of the brass spools got run on the belt sander to lower them.

Dad always sets up the magnet gap a little tighter on the top than the bottom, with the engine on its nose during setup. I think I just got it too tight. Less is not more! Model T's thrive on clearance, plenty of it that is. I should have put it together with no coil ring shims, the way it was when it came to me with a perfectly functioning magneto and gaps measuring .040 - .050".


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bud Holzschuh - Panama City, FL on Monday, August 12, 2013 - 08:38 pm:

Royce

I like your comment about T's thriving on plenty of clearance. In my limited experience I,ve found the same thing. I think I'll make it into a plaque for my shop wall.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Norman T. Kling on Monday, August 12, 2013 - 09:04 pm:

I meant 25 thousandths. I was not too good in math and 0's get me confused.
Norm


Top of pagePrevious messageNext messageBottom of page Link to this message  By Harold Schwendeman - Sumner,WA on Tuesday, August 13, 2013 - 12:04 am:

Thanks Garnet,.....and I'll try to only post this ONCE! Ha, ha,.....harold


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