Pintle hook super stiff- have advice?

[CoastieReid]

My pintle hook is the one that came on the M38.

I have to smack it with a hammer to make the jaw move- It's super stiff.

Any tips or tricks? I put PB blaster on it already. Short of soaking it in the ultrasonic cleaner- anything else I should try?

Before I go drilling out that split pin rivet looking thing and possibly destroying it.

Sure don't want to have to buy a aftermarket one because I am sure getting tired of spending my money on stuff I already have.

Thanks.

[jake138]

Mine was locked up solid as well. I cut the lid off a bottle of windshield washer fluid and soaked my entire pintle hook in Evaporust for a few days. Then it only took a few taps with the brass drift to get the latch to open. Once it opened, I removed the snap rings and drove out the pivoting pins.

[wesk]

There are several variations on pintle hooks for just the light weight class. Coastie I suggest you load a pick of you hook.

[RonD2]

Without seeing a photo of what you have, there's an exploded diagram in the September 1955 M38 ORD9 on page 271.

There's an internal spring on the latch that could be broken or rusted away and hanging up. All the pieces are cast iron, so as long as they aren't cracked or broken I'd think that patience with some oil would eventually work.

If I was going to soak it for rust, a gallon of vinegar is less than $3 and works quite well. Submerge it for at least a week.

Good luck!

[CoastieReid]

I can see there is a circlip on the the jaw. it's smashed..

[RonD2]

Can't tell from your photo, close-up photos would be better. Obviously, the snap rings ("circlips") have to come off those two pins in order to free them to push out the opposite side. Drilling them out would be a bear because they spin.

The ends of my pins that have the snap rings are also threaded for zerk fittings. The other ends are shouldered. The M38 TM says the pintle is equipped with grease fittings on those two pins, but later replacement pintles maybe not, and either would be "correct" for the M38.

From your photo, it looks like your zerk fittings are either missing or broken off.

In my travels I've not seen a ready source for pintle specific repair parts, but those pins may be common and available with some searching for general hardware. There's nothing unusual about the latch spring, I'm pretty sure I've seen them in the Hillman bins at my local Ace Hardware store, or very close to it.

My guess is that corrosion and a bad latch spring is your problem. Once I had it open I'd quit hammering it until I had it apart to see.

[jake138]

It looks like the ends of your pins have already been brutalized quite a bit. I would have to guess that at some point in history, someone saw your pintle hook and decided that their only solution was a large hammer. I'll try to get some photos of what mine looked like, but as Ron stated, I would have to agree that it looks like your zerk fittings were broken off at some point, probably with a hammer.

With the mindset of trying to save what you have, I would again suggest to soak the entire assembly for a few days. Clamp across something meaty in a bench vise and start hammering what's left of those pins out with a solid drift. If they still refuse to drive out, then you might seriously have to consider grinding or drilling them out. If you try to drill them out and they spin, that tells me you're stuck with not being able to hammer them out because the end is totally mushroomed over. At some point, you'll have to decide what can be cut and ground out versus what can be salvaged.

[RonD2]

I'd take it as easy as possible driving the pins out --- after first removing what's left of the snap rings. If that end of the pins have been mushroomed by Bubba you still might finess them out. Worst case is cut-grind the shoulder off the opposite ends and they should punch out easy.

My point is that the pins may be worth trying to save if possible. They're both the same diameter but different lengths. Finding replacement pins that have zerks might be hard to source. If you can get your pins out and the zerks were broken off you might still get what's left of the zerk out with a small easy-out or careful drilling. The zerks are 1/8-27 NPT if I remember correctly and you can buy a tap to straighten out the threads and put new fittings in. All cheaper than a replacement pintle.

If that fails, finding replacement pins without zerks is probably not hard to do. Might have to settle for cotter pin retainers instead of snap rings. Just have to remember to give them a squirt of oil once in a while.