Tightening Body Bolts - how much is too much

[Stage1gs]

Hello,

I am putting a 31 Fordor body on my frame and replaced the body blocks and bolts. How tight should the bolts be? This body has 3/8” and 7/16” body bolts. Should you torque them to say 20 and 30 ft lbs? Just pull them down with a wrench? Obviously you can tighten these too much and crush the rubber, but also don’t want a loose body.

Brian

[ddelproop]

That is a good question. I would like to hear comments on this as well.

With standard nut and lock washers I had an issue keeping them from loosening up and avoiding misaligned the doors from being tight enough.

For now I have modern lock nuts installed for which I would like to avoid using.

[BRENT in 10-uh-C]

Tighten them enough to flatten the lockwasher and stop there. If you need just a tad more tension for alignment, then do so. The bolts will remain tight as long as the frame is straight, and as long as you are not in a super dry climate that will take the moisture out of the wood.

It is not the end of the world when you are doing your annual 'nut & bolt check' underneath the vehicle if you find one loose. Just use your fingers and check for a spinning bolt or nut, and re-tighten at that time.

[Bob Bidonde]

Make sure the body is centered on the frame. There are rubber pads in the joints, so just snug the nuts enough to flatten the lock washers. There should be about 1/4" between the body and the running board splash aprons.

[Stage1gs]

Thanks everyone.. I torqued the bolts to 17 and 30 ft lbs because I wanted to be consistent but it seems awfully tight. But it’s repeatable��

Will readjust (loosen) them tonite and try your approach.

[BRENT in 10-uh-C]

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Originally Posted by Stage1gs

Thanks everyone.. I torqued the bolts to 17 and 30 ft lbs because I wanted to be consistent but it seems awfully tight. But it’s repeatable��

Will readjust (loosen) them tonite and try your approach.

Not picking on you, but I wish every Model-A owner would throw away their damned Torque Wrenches. In the near 60 years I have been working on Ford Model-As (-and trust me when say I have worked on a boatload of them!!), I have yet to see where a torque wrench was needed to properly make a repair.

[nkaminar]

Brent, Studies have shown that an experienced mechanic can fasten a nut or bolt fairly close to the proper torque, at least for the smaller fasteners. This fails for larger fasteners. I don't know where the dividing line is but probably when you get into 3/4 inch or larger.

[Tinbasher]

Brent your a man after my own heart. I remember working with a german tech and he'd torque by degrees. Tighten up the bolt, when snug give it a 20 Deg. turn. your good to go.
That would be on a 1/4 bolt. he just knew what he needed for each bolt size. We call it feel. The crazy thing was when you'd put a torque wrench on it it would usually spot on for the bolt size. JP

[Pete]

I did a couple of frame off's about 40 years ago, not for show, just stock driver's.
The only reason I could see that wood was used as the original body blocks was "cheap".
It is definitely not the best material engineering wise for that use.
I used steel blocks the same dimensions as the original wood. I tightened the bolts per the various torque charts in engineering manuals.
One of those cars is still running on the street and occasionally when I see the owner he still comments how tight and non squeaky the car is.

There is NO WAY you can get an accurate torque reading against a piece of wood. You can get a reading but it will not be the same if checked tomorrow.
Forget lock washers even if initially compressed. Saftey wire will keep from losing the nuts but won't help maintain torque.
If you have ever done any cost analysis, figure the cost of wood blocks against steel
blocks.Knowing Henry Ford's reputation, which would you have gone with?

[Bob Bidonde]

The destroyer of rear axle tapers is the torque wrench, the literature that specifies crazy high torques and the folks who practice what they read.

[BRENT in 10-uh-C]

Originally Posted by Bob Bidonde

The destroyer of rear axle tapers is the torque wrench, the literature that specifies crazy high torques and the folks who practice what they read.

Yes Bob, so very true!!

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