Nathan Plemons

Some of you know about my friend and the BlueDemon Well when last I mentioned it he had a terrible sound coming from the engine that sounded like a loose rocker arm, but it couldn't be adjusted out. He also suddenly had low oil pressure.

We decided that it had to be something with a lifter, so we pulled the intake and what did we find. One of his BRAND NEW Comp Cams Pro Magnum lifters had come apart! The ring that retains the internals had come out and thus you can pull the entire lifter apart. Luckily the ring is a RING and it couldn't get off of the pushrod, so we didn't send lifter parts flying through his motor. We looked at the lifter and it's internals were sticking out about a quarter of an inch. We pulled it completely apart easily. We put all of my stock lifters back in just to see if that took care of the problem, we have not been able to start it yet.

My question, could this exploded lifter cause low oil pressure? I'm thinking yes, because the oil just enters the lifter and expands and runs everywhere BUT where it is supposed to. What do you guys think? It really made us feel good when we saw the lifter like that, it made us think that we had indeed found the problem.

Thanks guys, this beast has been 6 months in the making and we are itching to actually DRIVE the stuipid thing.

365ZUM

I don't know, but I experienced the same symptoms when I blew my engine. The sound was coming from the 6th rocker arm on the passenger side. My oil pressure deviated, but would go down with the more gas I gave it. It would be dangerously low at some points (2-4lbs). I then limped to RP Motorsports, where they were POSITIVE it was blown. Maaaybe I'll get a second opinion :(

Nathan Plemons

Well in this case it BETTER NOT be blown. It's a brand new 396 stroker, built because he blew the 350. It ran alright for about 100 miles or so, then the oil pressure went WAY down. It still has pressure, just very little, maybe 10 psi. The wierd thing is that when it was running, it sounded perfect, and ran smooth, except for the obvious noises made by the valvetrain. We KNOW the sound of a spun bearing, and this wasn't it. We are hoping for the best. It would sure be a beeotch to blow up a $10k motor in 100 miles.


[Modified by Nathan Plemons, 9:52 AM 1/23/2002]

jvesalga

Yes, a lifter that has come apart can cause low oil pressure.

However, the thing I am concerned about is that you said you put the stock lifters back in. I assume you put the stock cam back in as well that goes to the stock lifters? A cam that has run must use the same lifters each lobe was run against. Each lobe has a unigue wear pattern and switching lifters upsets the grain and can cause undue wear or flatten some lobes. You can get away usually with new lifters on a used cam, but not used used lifters on a new cam or used lifters on a different used cam.

Nathan Plemons

You do realize that these are hydraulic roller lifters? People swap cams all the time and don't have any trouble with them. If you look at the lifters they roll freely and there is no visible sign of wear at all. (I know you can't judge a 1000th of an inch) However, if you look at the old cam that the lifters were running on you can see where the lifters ran, because it's clean the the surrounding area is browned a little from oil. As for feel however there is NO difference whatsoever, it is perfectly smooth.

Hydraulic roller's barely wear at all, and he's not going to run them long either, just long enough to see if that was in fact the problem, then he'll put his new set from comp cams back in. I can easily see your point for non-roller lifters, but I think with a roller it's really a non-issue.


[Modified by Nathan Plemons, 11:50 AM 1/23/2002]

LPDesRoche

People swap cams all day long with hyd. roller lifters and never change them. Its very common. That was an old flat tappet problem.

I think this lifter could be the source of your oiling poblem as well. I find it hard to believe that there are 2 things that wrong in a brand new engine. But I have seen stranger things.

Only thing to do is start it up and find out.

jvesalga

Yes I realize that, just my 2 cents. It sounds like you have spent a lot on the motor...in the scheme of things lifters are one of the lesser expensive parts.

Hope you get it taken care of, I hate taking motors apart...

Nathan Plemons

That's cool. I just didn't know if you knew. I'll agree with you, lifters are CHEAP compared to the rest of the motor, but we do want to make sure that's our problem. He'll have to pull the intake back off anyway, one of the holes in his head is stripped. It'll run without that ONE bolt in the intake, but he still wants to fix it. Which will lead to another post here in a minute.

We'll put it together, see if it runs, talk to comp cams, get the lifters, then take it apart again.

Goody

I'm inclined to say no, the exploded lifter isn't causing the problem. I say your lifter lost something else that has bound the oil pump somehow. Why would one little roller lifter cause a total lack of oil pressure?? I need one of those oil passage schematics to know for sure. You should still drop the pan to make sure nothing is in there. Why risk so much for so little? :seeya

VetNutJim

Hey Nathan,

You are right on top of this. You've got it figured out already
Both lifter galleys feed from the oil pump so if you pull one out or like in your case one self destructs and leaves the lifter hole open then oil pressure will go right down.

The hex head plugs for the lifter galleys are in the back of the block and there are just plugs in the front right behind the cam gear.
There is a line cast into the block down to the output of the oil pump.

On a rebuild most folks remove the hex head plugs in the rear and the regular plugs in the front and run a rifle/pistol cleaning wire brush thru there to clean out the lifter galleys.

My bet is with you. The oil pressure will be ok when you fire it back up.
Give it a good ol' oil and filter change when you get through and it'll be just fine.
Oh, you're right about roller lifters but I guess we all thought when you said "stock lifters" that you were talking about standard lifters (like all us "po folks" have :-))

Good luck with it.

yoslambo1@cs.com

where did you buy this engine?

Nathan Plemons

He built it.

It was a 350 block that he had clearanced for his Callies crank, oliver rods, SRP pistons, etc.

Basically we built it. There is nothing wrong with the theory, once the block is clearanced it is no different than a budget rebuild. This guy just has the worst luck in the world.

ANTI VENOM

If the lifter body was still in its bore and not sitting up to high to block the flow of oil, I wouldn't bet on the lifter. However, if the lifter was high or out of its bore, then (as Vetnutjim said) it could block the oil flow or not let it continue it path to the next lifter. It depends on how the lifter was, as I see it. Just my thoughts. Good luck.