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Most of us professional mechanics have a set like this. They clean the threads without cutting. Good for removing old thread sealers and loctite. And just generally cleaning threads.
I know about those - not a big discovery.
I thought you meant a tool that you can run in past the damaged threads and then expand it to size and back it out reforming the damaged threads.
Those are just thread chasers ........many times they do more damage than good
I easily slid the insert out from the cap and don't see or feel any scratches. I lost 1.5 threads from where oil pump bolt broke the end of the cap, all the remaining threads look/feel good. I ordered the ARP stud that you guys recommended and will install with red loctite and a more careful hand when mounting the oil pump. I was panicking when this happened, but everyone's patience and kind advice really helped! Thanks
I really think you didn't have the pump seated in place and had minimal thread engagement when you tried tried to tighten the bolt.
Probably because you didn't have the pump drive engaged properly
That is the only reason you broke out the first thread - NOTHING to do with oiled threads
Newbie mechanic "experience" lack of
I really think you didn't have the pump seated in place and had minimal thread engagement when you tried tried to tighten the bolt.
Probably because you didn't have the pump drive engaged properly
That is the only reason you broke out the first thread - NOTHING to do with oiled threads
Newbie mechanic "experience" lack of
Quite possible. I did feel it insert though and the mating surfaces of the cap were flush. I feel I dodged a bullet either way.
With all due respect, I would seriously reconsider using Red Loctite. Blue Loctite is more than enough. Personally, I think you'd be fine with no Loctite. The following is from Loctite's website.
Quite possible. I did feel it insert though and the mating surfaces of the cap were flush. I feel I dodged a bullet either way.
I don't think you made a mistake, except perhaps not checking the bolt length before assembly, and who would think of that? The same thing happened to me. The factory bolt was just too short. I suspect there may be a difference in the dimensions of the aftermarket oil pumps vs the factory original.
And I agree. Red Loctitie is overkill and will just complicate future disassembly. I almost never use it. Be aware there are at least two different blue Loctites, only one of which is meant for use in the presence of oil. Don't remember the numbers off the top of my head, but get the correct one and you'll be fine.
OP:
I don't know if or what you did or didn't do "wrong" as neither I (or others) witnessed failure. From afar, I cannot KNOW what happened; nor where any fault(s) might lay.
The Blue Loctite can-will weaken at higher temps; And laying adjacent to the business end of crank is likely to become plenty hot.
And, because there are only a few OE cap threads, and you've lost a relatively large portion of that; I understand it needs "help".
I understand you will stud the pump. With stud, it should seldom (if ever) require stud's removal from cap. So, make its juncture firm !
BTW, if you truly require RED Loctite juncture to break; simply pull cap, then heat it enough and it will give way.
I stick by the RED Loctite; or perhaps even GREEN. And, IF I were there to inspect and measure, might suggest forgo any Loctite; But substitute a careful (and Very quick) spot or two of TIG weld onto stud+cap (inside cap's insert-side of hole) to help prevent stud rotation/loosening.
But, we're not there to witness, measure or assess.
I easily slid the insert out from the cap and don't see or feel any scratches. I lost 1.5 threads from where oil pump bolt broke the end of the cap, all the remaining threads look/feel good. I ordered the ARP stud that you guys recommended and will install with red loctite and a more careful hand when mounting the oil pump. I was panicking when this happened, but everyone's patience and kind advice really helped! Thanks
I almost never use red locktite but that is one place that I would use it! If you ever need to remove it apply heat and unscrew... don't try to unscrew red loctite without heat! Make sure you clean the threads well.
The ARP Stud is going to have a socket, and you can turn it in with a Allen key. But you can also turn it in so far that it will contact the Bearing. You don't want to do that. Play around with it a bit and you will see what I'm talking about. They mention using Loctite as an option.in there instructions. I never have.
The ARP Stud is going to have a socket, and you can turn it in with a Allen key. But you can also turn it in so far that it will contact the Bearing. You don't want to do that. Play around with it a bit and you will see what I'm talking about. They mention using Loctite as an option.in there instructions. I never have.
Thanks for this tip! I will install the stud with the cap insert out so I can see the stud end and be sure of my depth.
Below are some photos showing just how short the oil pump mounting bolt is (and pump and bolt are both original). DrWet nailed it. It wasn’t that the cap, pump, or distributor shaft weren’t properly seated. It wasn’t a miscalibrated torque wrench. It’s that the bolt is only long enough to engage with 1.5 of the cap’s threads and those few threads couldn’t handle the torque spec. If the bolt had been a half inch longer, there wouldn’t have been any problem.
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Last edited by 78-Silver Bullet; Apr 1, 2026 at 01:47 PM.
Below are some photos showing just how short the oil pump mounting bolt is (and pump and bolt are both original). DrWet nailed it. It wasn’t that the cap, pump, or distributor shaft weren’t properly seated. It wasn’t a miscalibrated torque wrench. It’s that the bolt is only long enough to engage with 1.5 of the cap’s threads and those few threads couldn’t handle the torque spec. If the bolt had been an inch longer, there wouldn’t have been any problem.
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? how about a pic with insert removed, and pump installed & seated and bolt simply hand-tight --- so that we can see how far end of bolt is from journal side of hole?
regardless if stud has an internal hex for key (or not) you can also double-nut stud temporarily; to help measure-set depth into cap.
? how about capture same type pic with NEW fastener-stud as well ? Can we SEE how far down in the hole new stud is ?
*** perhaps that isn't an oil pump bolt at all? May be a head bolt ? Regardless, it's too short.
Last edited by Rebelyell; Apr 1, 2026 at 12:29 PM.
GM part number 3892678 bolt. 7/16 - 14 x 2". If that bolt is in the specific car line parts catalog rather than the Standard Parts Catalog that tells me it's a unique bolt for attaching the engine oil pump.
The bolt that SHOULD HAVE BEEN ORDERED is the one above the p/n 3892678 bolt - it's almost 1/4" longer.
That's what guys who know they are doing DO - order other similar parts JUST TO CHECK THEM OUT when they are building things , engines etc TO SEE what the difference is and maybe improve what they are doing.
I was just checking out my stock of oil filter bases that Mr L88 is looking for and got into my oil system parts and re-discovered the longer oil pump mounting bolts that I liked to use - photo below
