Hey guys, i heard something about how i should change out the spring in my oil pump to the blue one that came with it. The little card in the box says something about using it for HP corvette applications and originality? Thanks a lot guys for your opinions, it isn't in the car yet so it would be piece of cake to change. Thanks!

Daniel

Yes and while you are at it check the gear clearance,, preferably .001-.0015" ;)

Shove platigage between the gears as they turn? Would that be the easiest way? Thanks for the info smile.gif

Daniel

Definitely change it. It will make it perfect!

So it's the blue spring that is the hogher pressure one? I knew there were 3 of them at least, I just couldn't remember which was which.

So white is the lightest, blue in the middle and black is the big one? Is that right?


I always check my end clearance of pumps just like I do everything else....(slightly anal). I usually do like Mike says and do a little sanding to get it down to .001 or so, but I think every Melling I have checked has been no more than .002 which will work well. I know of some high $$ trick pumps that were having issues and this was the biggest issue,...one was .004 and pressure was always low. A new Melling fixed it right up!

Cheap and good!


JIM

Originally posted by Stikman33:
Shove platigage between the gears as they turn? Would that be the easiest way? Thanks for the info smile.gif

Daniel No, I think he means the clearance between the face of the gear and the flat cover plate.
If I'm wrong,....he will correct me and then feed me to one of his wolves.

I'm pretty sure it's the gear and the plate cover you take off... use a feeler gauge and measure against the sidewall tip. That's what I did anyway?

Hello,

I changed to the blue spring before installing my M77 also.

Good luck, Joe

Correct, the clearance or end play between the cover & gears,, Sorry about that I should have been a little clearer graemlins/clonk.gif
If you don't have a depth mike just get some brass shim stock. .002 should lock the pump & .001 should let it turn with a slight drag ;)

I guess this is heresy but I think the stock pumps provide enough oil except with very loose clearances and racing loads/revs.

I'm I wrong for using stock pumps in motors less than 500 HP?

Originally posted by jobberone:
I guess this is heresy but I think the stock pumps provide enough oil except with very loose clearances and racing loads/revs.

I'm I wrong for using stock pumps in motors less than 500 HP? This is a stock replacment pump ;)

Check behind me on this one but I think the spring pressure just makes the pump work harder the stiffer it is. My point is why suck HP from your engine trying to pump more oil when less is enough. But again that's street running. I don't race anymore and I used to race dry sumps anyway. It's all application.

I admit I feel better seeing 60-75 than 35 though

Originally posted by jobberone:
Check behind me on this one but I think the spring pressure just makes the pump work harder the stiffer it is. My point is why suck HP from your engine trying to pump more oil when less is enough. But again that's street running. I don't race anymore and I used to race dry sumps anyway. It's all application.

I admit I feel better seeing 60-75 than 35 though =
Yea,, especially if you are going to run the engine to 6000 RPM :D

The spring has almost nothing to do with normal running oil pressure, the bearing clearances & volume the pump puts out does.
You will not have any more pressure at idle & lower speeds.
It will just allow the pump to build more pressure, before it goes into bypass at higher RPM's which routes more oil to the bearings.
It is still a stock volume pump.
The spring we are talking about is the standard replacement spring that is recommended for the
HP 427 corvette engine.

Well, that should be good for me then smile.gif The motor this is going into is a 427 BBC with a 272/282 UD solid flat tappet cam! I appreciate all your guys opinions.

Daniel

How many springs come with the pump to begin with?

I just got the blue one...

Daniel

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The spring has almost nothing to do with normal running oil pressure, the bearing clearances & volume the pump puts out does.
You will not have any more pressure at idle & lower speeds.
It will just allow the pump to build more pressure, before it goes into bypass at higher RPM's which routes more oil to the bearings.
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That's my take. My point for most street engines you get adequate volume from a stock pump. Adding more oil might make you feel better but won't lub the engine any better than it's already getting...enough.

For hi perf engines I would take the more is better approach too. I hate it when things start making wierd noises in motors.

I was just going to start a post on this oilpump. What all do I need, oil pump & pickup screen? This pump comes with a spring right? Seems like everyone is replacing em'