1992 LA 360 low oil pressure.

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Patch

Patch

Patch
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Oak Harbor, WA. 98277
Hi all. Had a buddy who had his factory roller cam LA 360 rebuilt. Upon start up and run, in had low oil pressure and never developed good to high cold pressure. (This was like 10 years ago, so going by memory...lol) I have checked so far:
Driver and pass oil galley plugs are there
Plug under main cap is there (7.5 inches as measured from the oil sender hole)
Pulled the oil filter plate, 1 plug installed there.
Front galley plugs are there...both with oil pinholes in them
After I pulled the cam out, the cam bearings are toast.
There was metal in the bottom of the pan. This thing had like 5 minutes run time.
Am I missing something? When I say rebuilt, it could have been a driveway job...I don't know as I'm not in contact with the guy anymore. Could be that the cam bearings were bad to begin with and if they didn't change them....it had poor pressure from word go. It's going to go down to a full rebuild anyway, but thought it would be nice to know what was up originally. I know it's a total WAG at this point, but the shortblock is still as it was and together. Any ideas would be appreciated.....thanks!
 
What do you call "low" oil pressure?
 
Check to see that the oil pump bolts down perfectly flush with the rear main cap. Some bolts will jack one side of the pump up just a hair, with the result of a significant pressure loss. Also, check the relief valve in the pump. You really need to replace the pump anyway... metal pickup from the pan will go straight into the pump as it is before the filter.
 
Patch said:
After I pulled the cam out, the cam bearings are toast.
Click to expand...
Patch said:
This thing had like 5 minutes run time.
Click to expand...
Patch said:
it had poor pressure from word go.
Click to expand...
Ima thinking,that should have been caught during priming. Given your clues, it would seem pretty unusual for the cam bearings to be cooked tho.
But you know , on a lighter note, in order to have oil pressure at all; there has to be oil in the pan, and the pick-up installed,lol.
 
Rear oil galley plug, it’s near the distributor shaft bushing by 7 cylinder. Have a look.

Jake
 
AJ/FormS said:
Ima thinking,that should have been caught during priming. Given your clues, it would seem pretty unusual for the cam bearings to be cooked tho.
But you know , on a lighter note, in order to have oil pressure at all; there has to be oil in the pan, and the pick-up installed,lol.
Click to expand...
LOL....that would be true. Indeed they did put oil in, but priming I cannot vouch for. I wasn't there.
 
Sorry, I skimmed through at first but my brain goes to that since I had the same issue. If there is metal in the pan something bigger is going on.

Jake
Patch said:
Unknown....as far as maybe that run is plugged?
Click to expand...
 
Boy, a lot of assumption having to go on here. I'll take a stab. With what info was givien, I'm going to guess that the cam was tight in the bearings, and, upon start up, they either spun or the cam just chewed them up. ASSuming they were replaced at all.
 
408 swinger said:
Boy, a lot of assumption having to go on here. I'll take a stab. With what info was givien, I'm going to guess that the cam was tight in the bearings, and, upon start up, they either spun or the cam just chewed them up. ASSuming they were replaced at all.
Click to expand...
I'll take some pics of the bearings after I get off of work.
 
nm9stheham said:
Check to see that the oil pump bolts down perfectly flush with the rear main cap. Some bolts will jack one side of the pump up just a hair, with the result of a significant pressure loss. Also, check the relief valve in the pump. You really need to replace the pump anyway... metal pickup from the pan will go straight into the pump as it is before the filter.
Click to expand...
I believe I already pulled the pump. Wish I would have paid attention to that....
 
Here's the cam bearings. The hideous one is the number 3.

20200210_161751~2.jpg


20200210_161736~2.jpg


20200210_161824~2.jpg


20200210_161744.jpg
 
408 swinger said:
Boy, a lot of assumption having to go on here. I'll take a stab. With what info was givien, I'm going to guess that the cam was tight in the bearings, and, upon start up, they either spun or the cam just chewed them up. ASSuming they were replaced at all.
Click to expand...

S'kinda what I was thinkin.
 
Those are probably just the old original cam bearings. When they get a lot of years and age, the material gets brittle and breaks out.

That block looks filthy!
 
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