Talisman51

Hello...
Any melling oil pump oil pressure spring experts.... I am installing a new melling 55-HV pump, and am torn between using the high pressure spring (pink) or the supplied stock spring (blackt). The application is a 1965 327/365hp. The melling doc. says the pink will sustain 70 psi...which seems too high, while the black is for "stock" pressure relief. Hummmm....since the 365 has the 80lb oil pressure gauge I wonder if the application calls for something a bit higher than so-called stock.

Also, what oil pan gasket source do you recommend. I have a Felpro which is a honking big blue thing...dont look too original if you know what I mean.

Any wise old dog out there care to share some experience....?

Thanks as always,
JimV

Allcoupedup

Jim... I didn't know you were on this forum!

70 PSI is way too much. In fact, I am a believer in the stock pump - no High volume, high pressure needed for a street motor. About they only thing they do is suck power from the engine as it takes more physical effort to turn them. Extra wear on the cam abd distributor too.

I think my stock M55 Melling pump maxes out at 60 cold and about 45 warm - never had a problem - even at 6500RPM.

I'd go with the stock pump but if you already have the pump definitely go with the stock spring.

If you have neither, I have a M55HV in my basement that you can have for free - used but very good condition. it came with my 6 qt oil pan.


We need to cruise sometime. I drove behind a yellow 'vert down main street through downtown a few weeks ago. I see more midyears in G.E. than I do sharks!

brian

JohnZ

You don't need the high-volume pump, nor do you need the high-pressure spring; the stock pump will work just fine. The Fel-Pro one-piece gasket is a good piece - you can paint the edges orange after you install it, or you can use the good old 4-piece gasket if appearance is a higher priority than reliable sealing.

Subfixer

I used the 10% increased volume melling pump (10552) with the stock spring and the bolt on pickup (12557 for stock 7" deep pan)). I get about 65-70lbs cold and 50lbs when all warmed up.

Talisman51

Hello Brian and JohnZ...

Good to here from ya....

BTW..The yellow 65-66 (rally wheels) is a cousin of my neighbors...he has had that car for about 10 years now.

I am pulling the M55 out and replacing with the M-55HV due to low pressure at hot idle. I must have a high bearing clearance somewhere causing the M55 to fall short. I also have had excessive lifter noise which I theorize may also be due to low oil pressure. The Melling tech said the black spring will release at 60lbs...while the pink at 70lbs. I will definitely go with the black.

Thanks for the offer on the your pump...

JimV

Talisman51

Do you all recommend spot welding the pick up, or is that overkill...

Who would do it?.....Midas, machine shop...hummmm

Thanks again..
JimV

Allcoupedup

Jim, What do you consider low? My fresh motor with .003 main and .0025 journal clearances sees about 25 lbs at hot idle at 650 RPM or so.

BRian

Talisman51

Like 10 at hot idle.....Already verified it with mechanical gauge. The lifter noise is what really irks me. Also notice my repop dip stick bent at the windage tray and was interfering with the crank counterbalance. That was definitely a find. I am thinking that was causing some of my strange noises..


JimV

JohnZ

I doubt if the HV/pressure pump will do anything for you; oil pressure isn't determined by the oil pump, it's determined by resistance to flow from the pump, which is a function of bearing clearances. 10 psi at idle and noisy lifters confirm that you have an excess clearance problem; I'd fix that first before you have a more severe (and expensive) problem to deal with. I've built countless small-blocks with stock Chevy pumps, and have never had less than 30 psi at idle and 45-50 psi at cruise with stock-spec bearing clearances.

mrg

As an alternative to securing the oil tube pickup assembly to the oil pump body - I drilled and tapped a small hole into the body of the M55 oil pump flange that accepts the male tube end when my own rebuild was in progress. A recessed hex head set screw and blue thread locker secured things in place.

John

skids

Jegs has a bolt on pickup retainer for ten bucks you could check out!