Cotter Pin Issue

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PaintShaker

Junior Member
I'm looking over my newly purchased 31 pick-up. Many of the fasteners have a situation where a castle nut is positioned so far down on the threads that the cotter pin will never contact it. Maybe somebody used the wrong length bolt but even the special pitman arm bolt has the same problem. All of the bolts look original. Has anyone got an idea as to what may be going on? I'd appreciate any comments. Thanks.
 
Studs and nuts are special on old Fords. If someone has replaced them they are probably the wrong length stud or the thickness of the nut is not the same. My dad was a perfectionist when it came to using original Ford hardware. When I was a kid, he was in the Model A Club and there were two guys in the 60s that stripped Model A's to sell the parts. My dad would go over to their house and dig up the backyard getting all the original bolts and nuts they left on the ground. I still have coffee cans full of those Model A bolts and nuts. Even the later Mustang bolts the heads have special markings, when your restoring cars it's real important to maintain them. There's Nothing I hate more than a hardware store bolts on a vintage car. If you do put a washer under the nut on a chassis part, make sure it is a grade 8 washer. A grade 5 washer is not hard enough to hold the torque. It will eventually loosen; the nut will sink into the washer.
 
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even if you have all the original bolts and nuts in the correct position for the application you still may have this happen.
we tend to follow a book to set the bolts to a specific torq spec. that may position the nut at the wrong angle to get the cotter pin in.
some folks
- file the bottom of the nut so it will rotate a bit further
- back the nut off a tiny bit
- tighten the nut a bit more
- add a washer if the distance is too great
- swap the nuts and bolts around to find a set that will match.
- try new hardware.
- be inventive

there is probably more. i have found that very seldom the cotter pins line up perfect without some bit of manipulation.

it has been mentioned before that Ford factory workers did not use torq wrenches. it was done by feel and i would guess that would also include getting the nut to line up with the cotter pin hole.
 
old ugly said:
even if you have all the original bolts and nuts in the correct position for the application you still may have this happen.
we tend to follow a book to set the bolts to a specific torq spec. that may position the nut at the wrong angle to get the cotter pin in.
some folks
- file the bottom of the nut so it will rotate a bit further
- back the nut off a tiny bit
- tighten the nut a bit more
- add a washer if the distance is too great
- swap the nuts and bolts around to find a set that will match.
- try new hardware.
- be inventive

there is probably more. i have found that very seldom the cotter pins line up perfect without some bit of manipulation.

it has been mentioned before that Ford factory workers did not use torq wrenches. it was done by feel and i would guess that would also include getting the nut to line up with the cotter pin hole.
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But don't use a lock washer in place of the steel washer under the rear axle nut!
 
There are multiple lengths of castle nuts. Modern ones are mostly shorter than originals. This could be what you are seeing.
 
There are no washers under the nuts. I thought about trying to solve the problem with washers but I'd have to use two or more to get the nut where it belongs. Did ford use some extra thick washers?
 
I've thought about using grade 8 washers. As I recall, they are thicker than regular washers. Thanks for that suggestion.
 
What would be wrong with using Loctite and skipping the cotter pin all together? By the way, I'm quite sure all of the fasteners, including the nuts, are original. I did have some experience woking on another Model A, and these fasteners look the same. I'm surprised no one has come across this problem. I'm talking over 1/8" between the slot in the nut and the cotter pin hole.
 
PaintShaker said:
What would be wrong with using Loctite and skipping the cotter pin all together? By the way, I'm quite sure all of the fasteners, including the nuts, are original. I did have some experience woking on another Model A, and these fasteners look the same. I'm surprised no one has come across this problem. I'm talking over 1/8" between the slot in the nut and the cotter pin hole.
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I'm not a Model A guy but did Ford use castile nuts on them? I am VERY familiar with '39 / '40 Fords and there is not a single castile nut on those vehicles.
On the '39 / '40 Fords slotted head hex nuts were used in numerous places. And more often than not, if the slot didn't align correctly, the bolt had been replaced with one of incorrect length.
 
If it's drive train, steering, or braking related, safeties are a good idea. A nut fracturing is rare but a cotter pin may still capture a bolt for a while. In aviation, a person can use two washers on each end to get cotter pin fit. Bolts and nuts are standardized in shank length in 1/16ths and nuts are available in short or tall versions to cover such fit problems. Third Gen took over Ford Bolts and they supply a lot of original Ford hardware. Sometimes it's just a matter of getting the correct hardware.
 
cadillac512 said:
Functionally, nothing wrong. If you're not concerned with originality that will work just fine.
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I haven't ued split pins (cotter pins to you guys) for years on the brake clevis pins. For ease when I am adjusting them, I use "R" clips and leave them there.
I like easy!
 
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Purchase a copy of the Ford Parts Price List of July 1, 1931. Look up the part with the issue, and the Price List will show the authentic hardware the part is installed / assembled with.
 
Synchro909 said:
I haven't ued split pins (cotter pins to yoou guys) for years on the brake clevis pins. For ease when I am adjusting them, I use "R" clips and leave them there.
I like easy!
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I hate cotter pins (split pins) with a passion. I use wraparound pins ( reusable cotter pins). I am not sure what a R clip looks like? Is it the same as a hitch pin?

55409470769_bd113b7ee0_m.jpg
 
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In aviation, they used to use what we called diaper pins that were referred to as cowling pins by the manufacturers. They are available in three sizes. They have a tendency to rattle around some but they last a long time. I think Aircraft Spruce carries them. A piece of bent wire is better than nothing. I've found nails in some old farm equipment. What ever works.
 
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