What would cause the gear on the oil pump driveshaft to wear? I have a melling hv oil pump and milodon oil pump drive I think part number 21505 made from steel and it says the teeth are heat treated. comp ex295hl cam. There is a real fine metal flake in the oil that is really hard to see I am thinking it is from this and don't think it should have this much wear.
I will post pictures soon.

I haven't memorized the Comp nomenclature... is that cam roller (steel core) or flat tappet (iron core?).

I dont know the material. Its a hydraulic flat tappet cam. heres a picture

A steel gear on an iron (FT) cam generally works well. The HV pump adds increased load but the BB setup seems to handle it fine using a gear with hardened and tapered shaft tip and staked gear. Mine does. What makes you think its the OP gear creating flakes? Any sign of distress on these parts? Reason I ask is the HV pump on a BB with FT cam is a well proven combo.

Sure does look to me like the teeth of the gear on the oil pump drive are worn. If so, this probably is what your seeing in the oil. This wear is not normal and I dont know of a cause off hand. What weight oil you been running?

yea thats what I figured. 20w50 oil

20w-50 !!!! Why ?!?!?

The HV pump and the thick oil is putting to much load on the oil pump drive and wearing it out. Replace the driveshaft and run some lower weight oil.

Good advice. I still wonder why it appears to be failing. The BB setup seems pretty robust. Missed heat treat on the gear maybe? Unusually high oil pressure like 100+ lb on cold start? FWIW I run the MP shaft with hardened tip and staked gear on a 496 with 15W40 and its been fine.

Yea I thought possibly that the gear could have not been hardened I doubt it. I was recommended the 20w50 oil pressure is only 75 when I fire it up. but when it warms up the oil pressure at idle drops to around 12-15 pounds. What do you think throw some good 30w in? Maybe ill try the mopar shaft. Thanks for the help guys.

Cody

Guys people have ran 20-50 oil with HV pumps for years with out any issues. Just looking at the photo it appears the drive gear is not meshing squarely with the cam gear ? Setting to deep as though the bronze bushing flange isn't there or the bottom of the gears raised area that the bushing rides on isn't there. I looks like all the pressure is being put on the top side of the drive gear and appears to have tapered the gear splines on the drive gear. Is the bronze bushing in the block ?? In the photo the drive gear doesn't appear square with the block. Just a thought

logan426

Yea the bushing is there I think I would have some more serious issues if it wasn't. So I called milodon and was told that my cam thrust was not set correctly either too sloppy or too tight causing the gear wear. can you and how do you even set it on a hydraulic flat tappet cam. I could only see it being to tight causing the problem. So maybe I ll do a little more research.

I believe their speaking of the camshaft depth in the block or even possibly putting a thrust washer on the oil pump drive to adjust gear mesh ?? What timing gear set is on it ? Is it an aftermarket off brand ? Could the camshaft timing gear be offsetting camshaft more forward or rearward in the block ? Did your drive shaft gear go in hard and tight to start with and did you force it in ?

logan426

What the guy I spoke with was talking about was the camshaft endplay in the block either it being sloppy or pushed back in the block and making the gear to tight like you said. Im pretty sure it dropped right in. we did pull it and rotated it also when we put it in so it lined up with the distributor. It was a little hard to get out but thats because we had to get it out with the just the room of where the distributor goes I don't remember it being tight. I am running a 440 source doble roller timing chain. Can you even mess with the endplay or thrust on a hydraulic flat tappet cam?

I had this same problem with a small block Chevy it was eating the distributer / oil pump drive gear. I tried all of the different types of gears on the market the sintered( spelling ?) gear seamed to work the longest at about 1,200 miles all the others only made it about 900. My problem was the gear on the cam was cut wrong I changed the cam when I rebuilt the motor and the problem went away. I don't know how it stayed together with the shavings from about 9 brass, bronze, fiber and whatever other gears floating around the oiling system.

Now that would make some sense thanks for sharing. I'm still not sure what to do I ordered the mopar shaft not sure if I want to try that and see what happens?