what oil pump do i get for this engine

[78monteclassic]

Engine is not the original one it came with, casting code is 14094766, it's a 305

 

[bill]

Engine is not the original one it came with, casting code is 14094766, it's a 305

If its a stock engine, Id use the M55v or the M55 oil pump. The v pump is higher volume for higher performance applications. stock cruising engines would be fine w/the M55 model....imo.

 

[othtim]

You will be fine with an M55 or M55hv. Don't bother getting a pricey oil pump. If you want to spend money, get your pickup welded to the pump. Or get an ARP solid steel pump drive shaft.

 

[78monteclassic]

Thanks for the replies! I went with the m55 and got a new screen for it, I just need this to survive the winter, a brand new 350 is going in it in the spring! So no need for nothing performance. I noticed a valve ticking noise aside from the bad exhaust.leak it has and its driving me nuts!

 

[pontiacgp]

I use the M77 with the stock spring. It's a BBC oil pump but it bolts in and you just need an extension that that sell for the drive. It gives you about 15% more flow and a little higher pressure. The M55 have changed their design and have a problem breaking at the base.

 

[bill]

In the last 5yrs, Ive sold about 25 or 30 M55 pumps....have yet to see one come back to the store that has failed.

 

[pontiacgp]

Bill, Melling changed their castings and made them thinner in 2009 and 2010 and they had a problem with the casting breaking. There are still alot of them around. If you have a casting with a 5 digit part number then you have the old style before the thinner casting. Melling also had a problem with the powdered metal instead of billet steel for the gears but have gone back to the billet steel gears. Melling has also gone back to the thicker casting which are now called the M55A.

 

[bill]

Bill, you need to read a to keep up so you know what you're selling. Melling changed their castings and made them thinner in 2009 and 2010 and they had a problem with the casting breaking. There are still alot of them around. If you have a casting with a 5 digit part number then you have the old style before the thinner casting. Melling also had a problem with the powdered metal instead of billet steel for the gears but have gone back to the billet steel gears. Melling has also gone back to the thicker casting which are now called the M55A.

Ill look into that .... and thanks for the advice....I'll file it in the usual spot. Im sure the defected parts were most likely removed from the shelves from most retailers to eliminate any possible lawsuits. We get vendor recalls on hard parts on a regular basis...and I think this issue would qualify.

 

[pontiacgp]

There's a few forums that talked about it. When I put my engine together a couple of years ago there was quite a bit of talk about the M55. I was thinking about the M77 anyway and the word on the M55 didn't make me comfortable.

 

[othtim]

pontiacgp, i read similar threads online. I have in the last 5 years bought 2 m55HV's, and I haven't had a problem with either one, but they've been on what I'd call "mild" engines (sub-6000 rpm). Also another interesting thing - this time I wanted to go buy a better quality pump. So I pennied up for a moroso 22111 - opened the box, and discovered it is just an m55HV with some anti-caviation grooves and what appears to be better machining. basically an old-style melling housing. It even has the "M55HV" stamped right onto it. But still, it's been ayear, and i'm happy with it - hasn't broken yet 🙂