engine is out.......again......

[Blazer406]

Instead of hi-jacking the hyd roller cam thread again.....thought I would start a new one.

For those of you who have followed in the few other threads I have posted in..........or if you haven't.... here is what has happened to this point...

Junkyard SG1 engine built....bored .030.....stock rods...stock rolled fillet turbo crank....std/std ...crank removed straight out of the junkyard engine ...looked great....just polished it...high vol melling oil pump.....poor boy factory hyd roller conversion...218/218 cam....2 center steel main caps...line bored....roller master timing set...reduced center distance for line bore...

Engine was installed and cranked for the first time a few weeks ago....cold oil pressure was 50 psi +...... sounded great....but once the engine was hot...idle oil pressure would drop near 0.... rev the engine... it would go to 40-50 psi fairly easy...

After several posts in several threads....decided to pull the engine and check clearances on the rods and mains....(I wasn't there when the engine was actually assembled) thought I found the issue when the mains checked... .003, .003, .003, and .0035. The rods averaged about .0025. I got some coated .001 main bearings... and some coated .001 rod bearings and some coated std rod bearings. I mixed and matched the two sets of rod bearings to get rod clearances between .0015 and .002. The mains checked out at .0015, .0015, .0015, and .002.

Re primed the engine and reinstalled it a week ago... fired it up.....let it get hot..drove it about 30 miles....checked oil pressure idling.... same thing... near 0 idling.... would come up when you revv'd the engine some....

So... got a major leak or hemmorage somewhere. So I pulled the engine again tonight....

Will prime it up tomorrow night with the intake and valve covers off... to see if I can see where all the oil is going....

I will pull oil pan and somehow rig pickup in oil and see what it looks like coming off bearings....definately going to find this problem before it goes back in this go round.

On a interesting note... I pulled the engine in just under 2 hours... LOL... didn't really want to get good at that... but that's how it goes I guess.....

 

[GNBRETT]

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[84BuickGNYorkPA]

Is that a fresh oil pump on there, I wonder how a different pump would behave.....

Chuck

 

[Blazer406]

Is that a fresh oil pump on there, I wonder how a different pump would behave.....

Chuck

It was a high volume melling kit... came with the plates... and the longer gears... It was new when this all started...

 

[TurboDave]

While being dillagent in checking the rods and mains clearences, I don't see where the cam bearing clearences were checked. Sloppy cam clearences can dump a lot of oil pressure.

 

[turbo nasty]

What was the side clearance of the rods?

 

[Blazer406]

While being dillagent in checking the rods and mains clearences, I don't see where the cam bearing clearences were checked. Sloppy cam clearences can dump a lot of oil pressure.

I didn't.... I had the engine assembled. It was new (correct part number) cam bearings that my machinist did install.......and a new cam.

I'm expecting a mis-aligned cam bearing... maybe with oil hole sticking out.... or mabe one of the front lifter galley plugs missing or crooked and not sealing.

If both those check OK.... maybe oil pump clearances....

One thing is for certain... I will know what is hemmoraging my oil before it goes back in the car.

 

[Blazer406]

What was the side clearance of the rods?

Didn't measure it... but I do have a little.... I was checking to make sure they would slide a little back and forth on the crank journal when I last checked my clearances...

 

[Walt03]

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[cruzn57]

check the end clearance on the oil pump gears.

before you go any further,
read earl brown's oil pump/ cover blueprint, (turbobuicks.com)
I have done 3 of these, and get 30psi at idle on 70k motor(never been apart)
if you have the front cover off, use dial indicator before you remove oil filter cover, and ck end play, if its loose, it could be your problem.

 

[BIGPSI]

i just had a melling high volume pump lock up in my new motor.it was the pump out of my old motor with about 10k on it. cleaned it before install on new motor seemed ok,45 miles later it locked up,and took the cam and cam sensor with it.guess i learned a lesson always double check everything.

 

[Blazer406]

Nothing to report... yet

Wife had Bunko at our house tonight.... I stayed away.... too many hens.....

My boy has a ball game tomorrow night... but maybe I can mess with it for an hour or so late tomorrow night..... if not... definately will have some time Wednesday night....

Will keep you guys updated...

 

[charlief1]

subscribed

^^^ What he said.

 

[ttypewe4jim]

^^^ What he said.

^^^^ what they said.

 

[black owned]

im wishing you luck,as im ready to build me a poormans roller.

 

[Blazer406]

I got the intake off....got the priming tool priming..... I do have some oil coming out the tops of the lifter bores......not as much as coming out the turbo drain but if you combine all 6 it might be as much.... maybe more....

I really don't know what to make of it...... I've never primed another motor with regular lifters...and viewd the priming with the intake removed.....

Anybody prime their engine with the intake removed....??

 

[mikestertwo]

Anybody prime their engine with the intake removed....??

I have done it quite a few times. The turbo (non BB) does use a lot of oil and you do get quite a bit out of the top of the lifters. Check to see how much is coming out of the back cam journal.

 

[Blazer406]

Found the problem.....

After thinking about it last night... and some today.....I am convinced the oil I am seeing coming out the lifter bores is likely normal.... it is an ooze.... not a pumping stream....which is what I would expect if the flats on the lifters (for riding on the dogbones)... if they were going down low enough to get into the oil galley......

With that said... I decided to take the timing cover off...took the cam sproket and timing chain off.... I could then see the lifter galley plugs in place.... appear fine..... then I took my air compressor and pumped air into the block where the oil goes into the block from the oil pump......didn't see or hear anything alarming..... decided to pull rockers...pushrods...dogbones... lifters.... then pull cam to inspect cam bearings...cam started coming out... then stopped... wouldn't come any further... ??

Upon closer inspection.... the 2nd cam bearing from the front has spun and is stuck to the cam.... therfore not allowing the cam to come out thru the front cam bearing.... BINGO.... we have a winner.

I would not have ever imagined a spun cam bearing. Knowing my luck... we are going to find a dirt dobber nest that plugged the oil hole on that block journal......

My machinist said they make oversized cam bearings... the bearing looks like it is in decent shape from what I can see......

I guess this explains the loss of oil pressure?

FWIW... I am glad it wasn't my poor-boy hyd roller conversion.

I'll get the engine completely torn down tomorrow night... and get the block to the machinist Friday.

 

[Lee Thompson]

dig deeper !!!!!

I have had spun cam bearings. IMO, this is not your low oil pressure problem. Granted, it has to be fixed and is not helping BUT think about it. It is spinning in the bore (and unless it has moved forward or rearward) it is covering the oil hole. The 2 eng. that I had spin bearings lost no oil pressure. When repairing this spun bearing you MUST have heads and main caps torqued to desired value when they line bore the cam journals. Buy 2 sets of 87 bearings and use all the large bearings. There is .020 difference between the front and rear bearings as compared to the 2 center bearings. The 2 center being .020 smaller dia. out side. We all over torque the mains and heads which in turn distorts the 2 center cam journals. They are unlike the 2 end journals which have a mass of material holding them true. #2 and 3 sorta set out there with very little meat supporting them. This is why I ALWAYS torque heads on before I install cam. Once inserted it MUST turn freely with 0 drag. I even have a tool to relieve the offending bearing if it has drag. If it has drag and is not addressed, it will build heat once running and GRAB the cam juornal as yours did. With a HV pump and booster plate, believe me a spun bearing will not cause such a large loss of pressure--you have this problem plus something else going on. Best of luck.

 

[KevinB]

Also, check for cracks that run from the main stud holes to the cam bearing journals. Last fall I had a crack there. Lost all oil pressure. The bearing spun but also walked it's way out of the journal which left the oil hole in the wide open.