I noticed on 2 occasions today reading topics people having oil pump drive failure on high horsepower LT1s. Are they weak? Are they breaking due to higher loads from Hi-perf. oil pumps? I never heard of one brake on a stock LT1. If they are in fact weak, at what point they should be addressed? Can one even get a stronger/upgraded oil pump drive?

 

I've never heard of them being a weak link. If it were me and I was doing a rebuild where the motor would be spun higher than stock redline and/or using a high volume pump I would install a hardened oil pump driveshaft. I believe ARP makes one that you can get from Summit.

 

If anything is weak it's the plastic locator that becomes extremely brittle. One rebuild I did I took the drive off the oil pump and that plastic POS snapped in half. If the engine is stock or not I would always replace that crap for an ARP.

 

I dont think he actually means the shaft, he is talking about the drop-in unit/gear.

 

That's what I thought too. More Performance makes a retainer to go over the top of the drive that will keep it in place should the ear for the retaining bolt break. It's called the Oil Pressure Saver, about $20. Definitely go with the hardened shafts with steel coupler too. Melling's is about $7 at Jegs and the Moroso and ARP ones are $13-14.

 

All I was reading was "oil pump drive" failure, so I'm unsure if that means the gear or the shaft. I suppose it's the shaft...
So the ARP makes just the part to replace the plastic locator or it comes with the shaft? Anybody has the ARP part number?

 

No, they were talking about the drive. It's in the lifter valley and takes the place of the bottom of a conventional distributor that drives the oil pump in the non-LT1 SBCs. And yes, I have removed them and seen them cracked as well as having heard of complete failures. If you're into your engine for anything, inspect it well and if there's any doubt, replace it. If you know it's old, replace it anyway! And yes, the steel couplers come already made onto the hardened shafts, the way Chevy should have done it in the first place....

 

More Performance makes a billet cap that goes on top so if the tab breaks it won't shoot out of the hole and ya loose oil pressure.

 

Thanks guys. I will address that when I rebuild my engine this winter.

 

Anyone have a link?

 

More Performance

Phone: (704) 393 - 8241

Call them and ask about the LT1/4 "Oil Pressure Saver", their online catalog sucks.

 

i had an oil pump drive gear failure on my 94z. it really wasn't fun to pay $2000 to replace my cam, drive gear, oil pump, and driveshaft. if you have any doubts at all replace the gear. also make sure the materials are compatible. my mechanic said that it failed b/c of the HV oil pump, but he also said that if you use a billet steel cam w/ cast gear it will fail. he also said that you can never use too much assembly lube

 

Some billet cams have a pressed on gears made out of a different material than the cam. Ya need to run what the cam manufacturer recommends.

 

I have one I will sell you, new never used.

David

 

That # has been disconected. I cant find any More or Moore Performance website. Id like to get one of these before I put my intake on.