I've just read in a few posts that the High Volume Melling oil pump may not fit as the gears are thicker than the OEM LS1/6 pump.

Is this true? People ARE using it, so what needs to be done to make it fit, anything? I plan to re-use my OEM damper and an LS2 timing set on my '02 Z06.

 

It will work fine with the LS2 chain. I think what you might have heard is that with some double roller chains there may be a fit problem.

 

It is my understanding that because of the thicker pump gears the crank damper assembly will not sit as far back on the crank, possibly causing a misalignment of the crank pulley with the accessories.

I also read a mention that the timing chain cover needs to be clearanced for the HV pump as well???

 

Which Melling pump?

My crank had to be clearanced for my double-roller, but the pump and the cover were fine over the 296.

 

Link to a thread?

 

I have that pump in my 02 ZO6 with the LS2 chain and there were ZERO fitment issues and it workes excellent!! It has very very good pressure.

BC

 

Didn't keep the thread up, but read about a guy who had to clearance the front cover to fit the pump. Also just got off the phone with Texas Speed and the guy there said there are different castings for the front cover, some clear some don't. He wouldn't guarantee me mine would clear based soley on the year of the car.

 

You are correct a high volume pump does have thicker gears and a thicker pump body and does have fitment issues.
What the other people are doing is confusing it with a high pressure pump and entirely different animal.
To use the HV pump you will need to shorten the snout on your balancer the same amount as the increased thickness of the gears and then minior grinding to the interior side of the timing cover is required.
Or you can buy an aftermarket cover, I think QTP makes one$$$.
Really the stock pump works fine unless you have huge bearing clearences.

 

BINGO! That's what I was waiting to hear! Now as long as both of our '02Zs came with the same timing cover I should be set to go!

Question Bill, did you install the pump yourself? If so, did it need spacers to clear the beefier LS2 timing chain? Also, did you find the oil pickup tube difficult to disconnect and re-install? Did you put any form of timing chain damper in with the LS2 kit? Any advice you can give will be GREATLY appreciated!

 

Now I'm confused! One person says it works and another says it wont! The reasons you give here are the same I read before, and if the crank balancer is not shortened it causes a misalignment of the crank pulley with the other accessory drives, correct? Is that the only issue?

Is it possible that this issue is present in cars using this pump but the misalignment is small enough that nobody notices? Is the issue only present if the pump is spaced out to clear thicker timing chains?

Is cover clearance only an issue if the pump is spaced out for thick chains? Can you please describe your experience in detail? Thanks!

I agree the flow from my stock pump is more than adequate, but my oil pump has a sticking bypass (pressure relief) valve plunger... every now and then after a high RPM sprint, upon returning to idle speed the oil pressure will drop to 15-20psi. Reving it up again raises the pressure and "un-sticks" the valve plunger, and idle pressure is fine again at ~35psi hot.

FWIW my engine has ~120k miles on it and the Melling pump I'm refering to is the High Volume 10296 model. I figure with a "mature" engine who's clearances aren't getting any tighter over time, that a slight bump in oil flow potential couldn't hurt.

 

Mine has spacers on it and still fits inside the cover.

 

Were the spacers used soley for timing chain clearance, or was there another reason?

Did you machine your damper? Do you have any accessory belt issues?

 

Double-roller clearance.

Damper wasn't touched (it is a brand new OEM pulley - the u/d pulley that came with the car was wearing out). I haven't driven it much with this setup yet, but the belt looks true to me. I haven't tried the laser test.

 

I will look for the box my pump cam in. Sounds like there are several different Melling pumps. I can tell you for a FACT that the LS2 chain will FIT like a glove.... In fact,, the LS1/6 chain is NO LONGER available and the LS2 chain replaces it.

I do ALL MY OWN work. I'm going to Carlisle PA tonight so it may be a few day until I can look for the pump box (if I still have it) I return on SUNDAY evening if the HURRICANE doesnt wash us away!

BC

 

The 10295 is a high-pressure pump and the 10296 is a high-volume pump.

Almost everyone uses the 10296.

 

Ok....................... I couldn't stand it any longer.... I went out in the shed and FOUND the BOX..... Its a M295 soooooo,, thats why it fit without any issues,

Sorry for any confusion. That one works EXCELLENT and at idle with a BIG cam,, I do NOT have any pressure issues.

BC

 

Bill I'm jealous!!!

If you have a chance to talk with Lance Miller please say hi from Eric D

Have a great time!

 

He will be at the BURN OUT CONTEST Ill say Hi for you. I will also be seeing Tom Hill and hopefully Will Cooksey.. I met Tom at the Bloomington Event when we were giving the Corvette Maintenance Lectures. Hes a cool dude!


Heres a CUTAWAY picture of how the O ring fits in the pump housing:





BLUE ANGLE

When you get ready to change that pump,, I have some procedures and info that help make the job easier. What damper are you using????

What damper BOLT are you using?

Bill
Bill

 

When you get your pump,, it will come with TWO O rings. A thin one and a fat blue green one.. USE THE FAT ONE! Lube it up and it will slide right in.

BC

 

Bill, if you haven't seen Lance's movie “The Quest”, I would highly recommend it. I had the opportunity to see its Detroit debut.

Excellent!