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 Post subject: Lifter pump up
 Post Posted: Mon Jul 16, 2012 2:08 pm 
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I have an old Melling high volume oil pump that was made in America and I reused it with my current 455 Olds engine. The machine shop cleaned it out and I primed it before installing everything. I had the engine machined 30 over and internally balanced. I have adjustable roller rockers,and hardened push rods. The engine is about a year old and only on it's second oil change, excluding the engine break in oil. The pump still holds good pressure and reacts with the change in rpm. I currently use Champion 20w-50 synthetic street oil. Not a full race oil. Sometimes when I start it with the engine still warm from the last start up the. one or more of the rockers will click for a split second while the hydraulic lifters pump up. I could live with this on an old beater, but this was a brand new short block with new lifters. Is this the nature of the beast for a push rod engine, or should I look at installing better quality lifters. My machine shop used PBM. I don't know much about them, but I was happy with my machine shop as far as there integrity and service. I can't see this as an oil pump issue really, or is it. Wish I could circulate the oil before cranking the engine. Or maybe I could. I have a toggle switch on the power going to my HEI.

Just Primer


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 Post subject: Re: Lifter pump up
 Post Posted: Mon Jul 16, 2012 2:25 pm 
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Location: Elizabethtown, KY
You could put an accumalator on it and prime the system before you start it. Or like you said turn off the ignition crank it then start it.

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 Post subject: Re: Lifter pump up
 Post Posted: Mon Jul 16, 2012 3:10 pm 
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What is probably happening is that when the engine is off, lifters that are at or close to the nose of the cam "might" tend to bleed off through the check valve while it's sitting, which is probably aggravated by stronger spring pressure of this new build. You'd probably notice this more too the longer it sits between times you start it. Another thing is that the engine "usually" stops at the same place, ie, with the crank in somewhere the same place in the standard rotation,say, maybe with #6 coming up on compression stroke. See, this is why flywheels wear out over time, cuz the starter is always engaging at or near the same place every time.

Ennywho, I'm guessing that this goes away pretty quick, like as soon as oil pressure gets to that/those aforementioned lifter/s.

Steve's suggestion sounds good in theory but in practical use I'd say that it's worthless for this problem. Reason I say that is because if the lifters are indeed parked at or near the nose of the cam when they bleed off, then the 60 or so lbs of oil dumped from an accusump isn't going to overcome a lifter that's bled off sitting with 500lbs of open spring pressure multiplied by a 1.6 rocker.

RE: using the starter ? Nah, those lifters STILL don't have enough oil in them to prevent the lash that's present!! Only advantage might be that it doesn't happen as fast as it does with it running, BUT, may happen more times before they pump up.

Keep in mind that hydraulic lifters only pump up when the VALVE IS SHUT! ;-)

IMHO, drive it! ;-)

NEXT!! .....................

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 Post subject: Re: Lifter pump up
 Post Posted: Mon Jul 16, 2012 4:05 pm 
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So are we in agreement? The lifters are fine? Don't replace? I wouldn't mind pulling the intake and lifter tray, to see how the cam ware is, but I might just be a little bit of a perfectionist. I haven't seen any metal or sparkles or heard any sloppy ticking. Yes it goes away quickly as soon as the pressure hits.

Just primer


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 Post subject: Re: Lifter pump up
 Post Posted: Mon Jul 16, 2012 4:11 pm 
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Yeah, like I said, I'd drive it! I would, however, limit the RPM to idle until the noise is gone. ;-)

FYI, the anti-pumpup Crane lifters from "days gone by" (1960s) were notorious for this but I never saw a cam wipe a lobe because of it.


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 Post subject: Re: Lifter pump up
 Post Posted: Mon Jul 16, 2012 7:21 pm 
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Thanks Ken, Your like the abusive step father I never had. I had a friend that was always selling old Cars. He would buy them cheap and then sell them for a few hundred more. We saw many 60's and 70's beaters. Station wagons, Chevy's, Pontiac's, BMW's (big Mercury wagon). A lot of them would smoke a little on start up and the rockers would click for about two minutes and then they would run smooth as can be. I never thought that I would see an end to those days. Now I go to the junk yard and it's all rice burners and five percent American Iron. Sad to me to see most of it go to the crusher.

Just Primer.


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 Post subject: Re: Lifter pump up
 Post Posted: Mon Jul 16, 2012 8:32 pm 
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Abusive? :-k DAYUMN, I'm not THAT bad am I? O:)


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 Post subject: Re: Lifter pump up
 Post Posted: Wed Sep 12, 2012 5:22 pm 
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the olds motors have a cruddy oil system and the need for a high bleed lifter and opening up the oil feeds and putting in restrictors is good to keep them happy at 6000.
my old 425 had rhodes lifter and when warm they would rattle at low rpm as oil psi was low .
would clack its butt off after a long sit as i adjusted them at .005 down.
the stocker guys would block all but ..010 inside .. they never clacked!

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