Oil pressure woes

iwaxmyjimmy

iwaxmyjimmy

College Web Wheeler
Joined
Mar 10, 2007
Location
Greenville NC
So I've got a k5 that I've slowly been building over the last few years. I've got 60 psi at the sending unit by the filter. Priming the oil system I'm getting oil out if the lifter bores. With lifters in, valves lashed no oil out of the pushrods and I've verified the the pushrods are clear. I've rotated the engine some by hand and continued priming and nothing out the pushrods.

I first noticed it when I started it up and had some valve noise after putting the roller cam in it I didn't have a few valves lashed. Well when I popped the covers not much oil on the rockers. Tight end the rocker arms more started it up, had a high idle that was a vacuum hose undone. Connected it idled fine but still sounded like it needed lifters when I was adjusting the distributor. I guess I moved it to far it kicked back hard on the starter.

Well adjust it and start it up and runs fine sounds strong, but liter noise still. Pop open the valve covers and I noticed no oil on the rocker arms. That's what let me to put a mechanical gauge on it. That's at 60 psi, so I don't feel like a bearing is wipped out, there wasn't any knocking when it was running.

Right now I'm debating on pulling the engine, pulling the cam, the pan checking the cam bearings. Then pulling the galley plugs and blowing it all out. Unless anyone has another idea I'm down to try out. It's a stock LO5 TBI 350, I put a 5.7 vortec factory roller cam, factory timing set, it's a TBI block that I was able to drill and tap the 3 bosses in the center for the lifter spider. I'm really trying to keep from pulling the engine because I'll drop more money in it, lol. I've already got a cam spec'd from crower that I haven't ordered yet,but new valve springs and retainers are in the garage.
 
What would cause it? One of the cam bearings installed incorrectly and blocking an oil passage?
 
Croatan_Kid said:
What would cause it? One of the cam bearings installed incorrectly and blocking an oil passage?
Click to expand...

I remembered checking them when putting this cam in and they looked perfectly fine. The engine only has 74k miles on it, still has cross hatch in the cylinders. About a year ago, I got it rung with the factory flat tapper cam and it had great pressure on the dash, ran perfectly fine.
 
But with the roller lifters...no oil?
 
Croatan_Kid said:
But with the roller lifters...no oil?
Click to expand...

Yep, it's a stock replacement melling oil pump, new pick up that I tack welded so it couldn't have came off.
 
I'd lean towards the lifters then...
 
This is why I'm like wtf
 
Took out the oil galley plug above the timing cover. Spun the primer and my god oil everywhere. I'm so damn confused with this damn thing.


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If you are getting good oil to the lifter bores then you should be getting oil to the top end. The only route for the oil to get to the top end is through the lifters and up through the pushrods. If you haven't done so already you should check to make sure all the pushrods are clear. If you are getting no oil what so ever up through the push rods (and they are clear) I would imagine you have incorrect or defective lifters.
 
It's a TBI block, that has the lofter bores machined flat from the factory, some came with the center bosses drilled and tapped already. This one I had to drill. But they don't go deep enough to hit the main gallery. These blocks take roller lifters from 1989-2000 or whatever year the vette started using them. First set was a used set of GM roller lifters, this set is a brand new set of GM ones. All have a .842 lifter bore. The dog bones fit perfectly on the lifter bosses the spider bolts down perfectly. The pan was pulled after I got the engine out of the k5 when I moved into my house last year. I put a brand new melling oil pump and strainer, everything was cleaned well without disassembling the long block pas the timing cover and cam. Pushrods are OEM vortec 1996-2000 and lash perfectly, it's got self aligning rockers on it, it's a 1999 5.7 vortec roller cam.
 
I understand that, but the lifters may still not work. You need to make sure that the oiling hole for the lifter does not come out of the bore and that the oil channel in the lifter stays in alignment with the oil galley of the lifter bore. If you have good oil pressure to the lifters and clear pushrods, the only issue can be the lifters or bores.
 
Ahh Here is a cut and paste from Jalopy Journal that better explains:

Be careful ... I read in a magazine that all engines from 87 and later that aren't roller from the factory (they came flat tappet) will accept the factory roller stuff ... I had a 1987 Monte SS engine on a stand, pulled the intake and sure enough, there were "stumps" or "bosses" that the magazine described to allow the mounting of the "spider". I then pulled the timing chain and sure enough, there was the machined area for the cam retention plate and the drilled holes to go with it just like the magazine said. Seems the magazine was correct after all ... NOT. Long story short ... all of the roller cam stuff DID fit on the engine BUT the lifter bores (for no apparent reason) were "stepped" (from the factory) and therefore exposed the oiling passages of the roller lifter. The stepped lifter bores worked fine with a flat tappet but did not work with the roller lifters (I found this out after assembling the engine and running it on a run stand). If you want pictures and more explanation search "roller cam borntoloze" here on the hamb.
 
NC-V said:
Ahh Here is a cut and paste from Jalopy Journal that better explains:

Be careful ... I read in a magazine that all engines from 87 and later that aren't roller from the factory (they came flat tappet) will accept the factory roller stuff ... I had a 1987 Monte SS engine on a stand, pulled the intake and sure enough, there were "stumps" or "bosses" that the magazine described to allow the mounting of the "spider". I then pulled the timing chain and sure enough, there was the machined area for the cam retention plate and the drilled holes to go with it just like the magazine said. Seems the magazine was correct after all ... NOT. Long story short ... all of the roller cam stuff DID fit on the engine BUT the lifter bores (for no apparent reason) were "stepped" (from the factory) and therefore exposed the oiling passages of the roller lifter. The stepped lifter bores worked fine with a flat tappet but did not work with the roller lifters (I found this out after assembling the engine and running it on a run stand). If you want pictures and more explanation search "roller cam borntoloze" here on the hamb.
Click to expand...

Damn it, so a retrofit hydraulic roller would possibly work?
 
Just went back out to the garage, yep that's exactly it. So seems like flat tappet or retrofit roller lifters.


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I'd leave the roller cam in it and change the lifters! Told you it was the lifters :D I was right and didn't even know why!

Edited for a good spirited ribbing: @iwaxmyjimmy
 
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