Installing head bolts: Opinions?

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Model T Ford Forum: Forum 2011: Installing head bolts: Opinions?
Top of pagePrevious messageNext messageBottom of page Link to this message  By Steve Jelf, Parkerfield, KS on Wednesday, August 31, 2011 - 01:09 pm:

Dry threads, non-hardening Permatex, or ???


Top of pagePrevious messageNext messageBottom of page Link to this message  By CharlieB Toms River N.J. on Wednesday, August 31, 2011 - 01:17 pm:

Did mine with a spot of oil on each. Other opinions to follow. I will tell you this: I don't remember where I got the info from but rod out each bolt hole with a pick or some such thing and use compressed air to blow out the stuff. You won't believe what comes out. Lord knows how it gets in there in the first place. It can cause the bolt to bottom out on the junk and pull the threads. It may have been Fahenstock or directions that came with the new head gasket but please don't fail to do it!


Top of pagePrevious messageNext messageBottom of page Link to this message  By Tim Voss on Wednesday, August 31, 2011 - 01:20 pm:

Remember to retighten after you start and heat up your engine.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jerry VanOoteghem on Wednesday, August 31, 2011 - 01:29 pm:

Steve,

Oiled threads & clean out the holes as Charlie says. You could also run a tap down the threads to clean out any extra junk.

Torque to 50 ft-lbs & retorque per Tim's suggestion.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ricks_-_Surf_City on Wednesday, August 31, 2011 - 01:50 pm:

Oiling the threads lets them come out easier, too, before you want them to. Torque specs are for (clean) dry threads.

I use studs, snugged into the block, then torqued to spec with the nuts. The turning and tearing of threads into the cast iron block will cause stripping eventually, whereas studs snugged into the block cause no such torture, just a straight pull. The modren Model A uses studs.

For those few holes where you can't put the stud in in advance, you can tape those studs into the head, then snug them in with a jam nut.

If you don't like the look of studs and nuts, there's always acorn nuts.

rdr


Top of pagePrevious messageNext messageBottom of page Link to this message  By William Harper . . Keene, NH on Wednesday, August 31, 2011 - 01:51 pm:

Yes, a tap will clean the threads. You should then take a drill bit and by hand turn it into the accumulated compacted carbon and what ever else may be at the bottom of the hole to brake it up for removal. Compressed air into the hole is messy. I use a vacuum or dip the end of the drill bit in some oil and put it back into the hole. The loose crud will stick to the bit.
Good luck with your project. Bill


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jerry VanOoteghem on Wednesday, August 31, 2011 - 01:59 pm:

Ralph,

Any torque spec. I've ever seen noted "lightly oiled threads".

You really believe an oiled head bolt will back out? Overcoming the friction of the head against the block?

"The turning and tearing of threads into the cast iron block will cause stripping eventually"

Not if they're oiled or better yet coated with Never-Seez


Top of pagePrevious messageNext messageBottom of page Link to this message  By Steve Jelf, Parkerfield, KS on Wednesday, August 31, 2011 - 02:27 pm:

Yep, I'll clean & vacuum the holes, run a bottoming tap down them, and vacuum again.

Cleaning loose rusty debris out of the water passages: Put duct tape over all the water holes in the top of the block; attach a shop vac to the water inlet; with the vacuum running pull the tape off one hole so air going in that hole will carry crud to the vacuum, put the tape back on, and do the same with all the other holes.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ricks_-_Surf_City on Wednesday, August 31, 2011 - 03:13 pm:

I've posted this a number of times before. Anybody have a more authoritative source? I've read that at a mechanic's school they torque to rated spec both ways, and the bolts with the lubed threads break.



Dry torque rating for T size head bolts is 55 ft-lb. At the extreme, with graphite & oil lube, the bolt can take only half the dry torque before failure.

rdr


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jim Thode - Onalaska, WA, USA on Wednesday, August 31, 2011 - 03:39 pm:

Ricks,
I may read the chart differently then you. For a 7/16 14 grade 5 bolt the dry torque is 54 ft-lb and for the same bolt with graphite and oil lube the recommended torque is 49% of 54 = 27 ft-lb. I believe that either way, dry or with lubed the end clamping force or tension on the bolt should be the same. It just take more torque to get the same clamping force with a dry bolt and that makes sense.

Of course it follows that if you torqued a lubed bolt the same as a dry bolt, you would over stress the bolt and run the chance of striping the treads or breaking the bolt.

I have used bolts coated with copper coat gasket compound torqued to 30 ft-lb on my T with good results.

Jim


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jerry VanOoteghem on Wednesday, August 31, 2011 - 03:40 pm:

Ralph,

I would assume a grade 8 bolt at 78 ft-lbs dry or, as my reference states, 58 ft-lbs lubricated.

So, 50 ft-lbs is about right for lubricated threads.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Lewis R. Rash - South Hill, Virginia on Wednesday, August 31, 2011 - 04:09 pm:

Ricks, Would you scan the front of that book for me?

Lewis


Top of pagePrevious messageNext messageBottom of page Link to this message  By Noel D. Chicoine, MD on Wednesday, August 31, 2011 - 04:24 pm:

Jerry, I believe that it's not the number 8 bolt that strips but the threads in the cast iron block. I wouldn't mind replacing an occasional head bolt but don't like having to helicoil the block. Been there-done that, will probably have to do it again!


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ricks_-_Surf_City on Wednesday, August 31, 2011 - 04:42 pm:

Sorry, I should have referenced the page. Scanning is not easy for me right now, so here's the info:

POCKET REF
Thomas J. Glover

The 500+ page 3x5 book is chock full of formulas, specs, etc. It's found near the cash register of better stores: autos, electronics, etc., and costs $10+.

Since head bolts of the era are unmarked, and they didn't have torque wrenches, I would guess the original bolts to be no better than Grade 5. What do the vendors say? More important, what does Jersey George say?

Bolts are supposed to be torqued tight enough to stretch, which means they are really good for one time use.

The nut/block doesn't have to be near as strong as the bolt, btw.

rdr


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Dare on Wednesday, August 31, 2011 - 05:12 pm:

clean the block threads, compressed air to blow it out, copper cote the threads of the bolts, copper gasket and copper gasket spray, 20lb,40lb, 60lb done., PS, if any head or block work ( removal ) has been done, rotate the crank prior to fastening down to ensure no strike between piston and head.

David.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Vince M on Wednesday, August 31, 2011 - 05:15 pm:

I recently purchased new head bolts from one of the vendors. They arrived already coated with a thick oil.

Vince


Top of pagePrevious messageNext messageBottom of page Link to this message  By CharlieB Toms River N.J. on Wednesday, August 31, 2011 - 07:24 pm:

Just make sure the stuff comes out of the bolt holes Steve. That's why I recommended compressed air. It is messy but the problem is the stuff is in there in the first place.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Steve Jelf, Parkerfield, KS on Wednesday, August 31, 2011 - 07:47 pm:

Yep, I'm running in a bottoming tap and cleaning out the holes, and measuring to be sure the bolts go in far enough.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jim Weir on Wednesday, August 31, 2011 - 07:59 pm:

When I put this engine together the first time, like the first one, a new head bolt stripped the block @ approx 30 Foot pounds. and like the first block, I put helicoils in all 15 holes. I use copper anti-sieze on the threads and 45 Ft/Lbs.

Sincerely

Jim Weir


Top of pagePrevious messageNext messageBottom of page Link to this message  By Aaron Griffey on Wednesday, August 31, 2011 - 11:13 pm:

45 ft.lbs is enough when you use the coarse thread bolts. 50 max. The head does not have to be that tight.
If you use model A studs you need to torque the fine thread nuts to 37 ft.lbs. to get the same gasket crush as 50 on coarse threads.
Multilpy the coarse torque number by .75 to get the fine thread torque.
So if you put in studs and torque the fine nuts to 50 it will be the same gasket crush as torqing coarse bolts to about 68. (68 X .75=51).


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bob McDonald-Federal Way . Wa. on Wednesday, August 31, 2011 - 11:51 pm:

You can always measured the depth of the hole and make sure that the bolts arn't to long or to short, after doing the cleaning of each hole as stated above.

Bob


Top of pagePrevious messageNext messageBottom of page Link to this message  By George - Cherry Hill New Jersey on Wednesday, August 31, 2011 - 11:53 pm:

RD....

My guess would be that at best OEM Ford bolts were grade 5. Never tested one and one of these days I just have to get a pocket Rockwell Hardness Tester...I can factor a Rc # back into a tensile number on steel and steel alloys.

Yes, bolts do need to stretch to 'work' and 'creep' over time can make them stay that way.

I've accepted the 50-55 with a 'wiped down' bolt...not acetone dried, not dipped in something. Not sure if it is 'right', but it seems to work.

The biggest conern I have is that all of those tables regardless of source are based on the load being distributed over a thread length of 1.5 times diameter for a cast iron/steel match-up, and 70% thread mating...and I've never been able to convince myself that Ford did either!

Just a joker...I have NEVER owned a torque wrench...but was smart enough that as my boys came up their own tool kits included some real good ones :-)

Whats the right torque? Find the average pull for an average man using 15 degrees wrist twist and 15% shoulder swing...No hip swing...on handed right predominent. (Lefties usually have less pull...lol). Theres a table somewhere, I'm in USA on holiday and have no IE books about. Then measure the spud wrench from the center of the head bolt hole to the center of the spark plug hole where it is gripped.

Multiply the one by the other, and divide by 12....thats the torque Ford intended in the first place :-)


Top of pagePrevious messageNext messageBottom of page Link to this message  By David ONeal on Thursday, September 01, 2011 - 08:52 am:

Gee whiz guys....Its just bolting on the head.
1. Make sure the holes are clean
2. Make sure your bolts are good to re-use or new.
3. Slap some anti-seize compund on the threads and torque per ford Model T specs.
4. Run engine to operating temp then re-torque.
5. done.

Were not sending the old Tin lizzy into space.
Dave


Top of pagePrevious messageNext messageBottom of page Link to this message  By Steve Jelf, Parkerfield, KS on Thursday, September 01, 2011 - 09:03 am:


Oh yeah?


Top of pagePrevious messageNext messageBottom of page Link to this message  By CharlieB Toms River N.J. on Thursday, September 01, 2011 - 09:30 am:

Slightly OT: I heard somewhere (probably here) that the professors car was restored after the movie.Does it still exist?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Anthony Bennett on Thursday, September 01, 2011 - 10:03 am:

When you're doing anything up, the idea is to stretch the fastener without overcoming it's strength. You're preloading it. Measuring torque is just a symptom of what you're actually trying to achive.

As Ricks has shown you might need up to 50% more torque to attain the same clamping force if the fastener is dry. The problem is that dry threads aren't as consistent as lubricated ones... (think about how some gall and some don't) so you end up with a lot of scatter in actual applied load from one bolt to another.

If you buy ARP bolts for performance applications they supply explicit instructions to use (graphite) lube in a tube expressly for the purpose... and the specs are about 15% higher if you use oil. Either way it is as important to lubricate under the head as it is the thread. Hardened washers help too.

Studs and nuts are a great idea in dodgey old cast iron blocks but I'd guess 40 ft/lb is as much as you need...

just my 5c

cheers

AB


Top of pagePrevious messageNext messageBottom of page Link to this message  By George - Cherry Hill New Jersey on Thursday, September 01, 2011 - 11:23 am:

Ahh....got two emails this morning asking if I was being cute with Ralph or being serious when I mentioned the wrench length...

For others and lurkers who may have the same thought...

Before we had torque wrenches, before we really understood what foot-pounds were...yes....the wrench length was BY DESIGN and not just to make matched sets look pretty and proportional for identification! Much of this has been lost in these fancy wrench sets you can get today, yet it was 'by reason' a century ago and why most manufacturers of EVERYTHING industrial supplied wrench and tool sets with their product. Find an IHC wrench of the era that has the same ends as the T-1917 but is a stubby? IHC had their reason, folks were breaking things so rather than strengthen the part, they shortened the wrench :-)

Today, just about everyone I know doesn't think twice about sliding a box end over an open end for that final 'ummmph' with extra leverage and I just shake my head at the practice, they only get away with that when they do because alot of stuff today is coming out at Grade 8 standard in the industrial world...but I think doing something like that on a Lizzy is just begging to look for a Heli-coil kit.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Hal Davis - SE Georgia on Thursday, September 01, 2011 - 11:47 am:

You guys all have it wrong. Just tighten it till it strips and back off a quarter turn.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Erich Bruckner, Vancouver, WA on Thursday, September 01, 2011 - 06:30 pm:

Hal, that observation deserves the "Mr Fordwrench Award"

http://www.flickr.com/photos/bruckzone/3719684016/in/set-72157620616047410


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce Peterson on Thursday, September 01, 2011 - 06:37 pm:

George is correct. There are no factory or Ford specified torque limits for any bolt on a Model T. The proper torque was / is achieved using the proper length wrench and an average pull on that wrench by the average guy.

I agree with Ralph on clean dry threads. Adding oil or anti seize means you can more easily pull the threads out of the block. Particularly the pre - 1916 blocks cast by Dodge brothers for Ford, the iron quality is just rotten. I torque the early heads to the block at 45 lbs dry. If you use oiled threads reduce the torque by 35% as per the chart Ralph posted.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Kohnke Rebabbitting on Thursday, September 01, 2011 - 11:29 pm:

If you can pull the threads out of any Model T block, the hole in wallowed out, and should be fixed. They should all with stand 50 Foot Pounds. We don't use Heil-Coils in Model T Head bolt holes, they have there place, but not there for one. What we use is a over size plug installed, with the I.D. stock thread size. If you don't use oil, which we don't, as we use Permatex "300". It is the black tar type, which has been used from Model T's on up untill the gaskets were changed in the late 50's, or 60's. One thing I will say, if you used Anti-seize, and the bolts came loose, somebody gave up on the Head torquing to early. The head bolt holes have to be cleaned out to bare metal, as some said, because no self respecting head bolt will pull on any thing that is loose. That includes a bottom tap run in. Now screw a bolt in, to see if it has much wobble, from side to side. If you are doing this many times a Month, you can tell by looking. Now is the time to fix them if need, not when the head is about torqued. one thing, the reason we use Permatex "300" on the end of the bolts is, Every now, and then there is a crack down in the thread hole, or the head bolt hole is drilled into the water jacket from the factory, and the 300 will seal the cracks, and also lubricate the threads, and it won't let the bolt hole rust so bad. Using 8 Grade bolts hurts nothing, just don't go over 50#. We also use the 300, on Model A's, and B's, also on head gaskets, Pan gaskets, Hog's Head felt to stick it to the Block. It works good try it before you turn your nose up at it. Herm.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jim Thode - Onalaska, WA, USA on Thursday, September 01, 2011 - 11:51 pm:

David ONeal wrote:
"Gee whiz guys....Its just bolting on the head.
1. Make sure the holes are clean
2. Make sure your bolts are good to re-use or new.
3. Slap some anti-seize compund on the threads and torque per ford Model T specs.
4. Run engine to operating temp then re-torque.
5. done."

I think the whole problem is that there is NO "torque per ford Model T specs" Is there??

Just revert the the shade tree mechanic method, tighten till it feels right and if you did not break something, it must be good to go.

Jim


Top of pagePrevious messageNext messageBottom of page Link to this message  By Paul Mikeska - Denver Colorado on Friday, September 02, 2011 - 12:26 am:

In my business we deal with this on a daily basis. Bolt torque is strange stuff. Dry torque is a NASA sort of process where the male and female threads are stripped of ALL lubricants. This may be a chemical or physical process. The oil from your fingers will lubricate any fastener. I wish that dry torque was not listed as it is not something that is available in the real world. Pick up a “dry” bolt with your fingers and apply “dry” torque to it and the chances are that it will fail. Pay special attention to Ralphs chart. The type of lubricant used with any fastener makes a bunch of difference as to where the fastener will fail with respect to torque. Add to this bolt grades and your head will spin.

So…. I use nickel anti seize on my head bolts and torque them to 40 LBS with a torque wrench. I re-torque them after running the motor and getting it hot. Your mileage may vary.

Paul


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Dewey on Friday, September 02, 2011 - 01:16 am:

Back to CharlieB's question:
There were multiple cars used in the movie, at least 3. Two of these I know survive--one was in Grass Valley (CA) and may still be there. I think the other is in S. Calif. The flying car had no engine in it (who needs an engine when you have flubber?--actually, it made it easier to "fly" on the stage).
T'
David D.


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