stevieturbo

Just changed from an LS6 based motor, to an LS2 based.

Short motor was supplied built from reputable source, and appeared all good....I built up the rest using previous heads/cam etc etc.

Re-used old rear cover ( I assume same LS1/2 and LS2 ?? ). Oil pump is used, but not old, and was working perfectly on my last build befire I had a whoops. Oil pickup etc is also same. I didnt install new o-ring, but old one was perfect.

Ive drilled/tapped a new oil take-off in the billet valley cover for my oil pressure gauge, and feed to supercharger. So basically its the same location as the LS1/6 block at rear

Ive tried winding the engine over, no plugs etc installed. Whilst I am getting oil circulating, oil pressure is only like 5psi max.
I do get a trickle of oil from the feed via the valley takeoff I installed.

If I blow back into this, you would think there is an open gallery somewhere ( tried via mouth, and an air source )

If I crank engine with oil filter removed...I do get a flow of oil from the pump to filter...although TBH, not as much as I'd have expected. But not bad.

I did check before assembley, and it did appear the rear oil gallery bung was installed ok.


Am I missing something blindingly obvious here that could be the problem ??

njc.corp

have a look into that-

stevieturbo

Possible I agree.

But as I say, this one is only say 3000 miles old, was in perfect condition, and installed nicely into the oil pump.

I wont discount the possibility though.


it doesnt however explain the apparent open oil gallery when I blow into them via take off I installed to the valley cover for my gauge and blower feed.

njc.corp

steve i cant comment on the oil gallery as i have not had that problem-

but i can comment on the oring-

what seems okay by eye aint always the case-

which leads to the second point-why would u not change the o-ring at the start-

not trying to put u down-

if everything was done u could work on the oil gallery problem if it is that-

now u have 2 issues (maybe) the o-ring and the oil gallery

u look at the pump from the inside? everything in order-

stevieturbo

Oh I fully understand.

Simple reason I didnt change it...is because it was perfect, and felt nice and snug when installing the pickup pipe.
I seen no reason not to re-use.

bad2dbone

iTrader: (37)

after my build with mine no ill pressure either and my oil pressure sensor in the back was broken so make sure that isnt the case mine didnt look broken either try that bro

stevieturbo

I dont use a sensor. Its a takeoff for a mechanical gauge, and I have confirmed gauge is working with air pressure.

As also stated...oil flow from this takeoff is minimal Just a trickle at cranking speeds.


Either there is a pickup problem...or an open gallery somewhere. Which Im leaning towards...but baffled as to where.

Either way...engine is back out tomorrow

Shawn @ VA Speed

iTrader: (3)

was the frt oil galley plug installed?

stevieturbo

There was only one open orifice on the front of the block...which corresponded with the oil pump.

Ive re-chcked that with photos, but sure 100% anyway.

because it was on the stand most of the time...I never took any pics of the rear.

When I blow into the oil galleries from the valley cover, it really does sound like there is an opening very near the top or rear.

Shawn @ VA Speed

iTrader: (3)

one last thought,are you running the same lifters?seen some lifters where the oil band would come out of the lifter bore.

stevieturbo

New LS7 lifters..


Was previously using Morel's

Shawn @ VA Speed

iTrader: (3)

well,i'm out of ideas

stevieturbo

me too....but i'll find out tomorrow !!!!!


just bloody hateful having to rip it out again. was hoping to have it running tomorrow. But it isnt worth the risk of not being right.

Shawn @ VA Speed

iTrader: (3)

good luck,keep us posted on what you find

67SS509

iTrader: (25)

Can you post a pic of the front of the block without the timing chain cover on it?

stevieturbo

Its a little dark, and a bad angle...but thats best pic I have.

stevieturbo

A new cam cover plate was used.

Im using the LS6 timing gear and front cover, as I dont use any of the factory triggers.

67SS509

iTrader: (25)

Can't tell for sure from the angle of the pic and the glare but what I was looking for is the oil gallery cup plug. It goes just to the right of the oil pump in the block. New blocks do not come with it installed. Yours looks like it is missing but I can't tell for sure. Do you have a pic from a right angle.

stevieturbo

If you mean here....




Yes it is installed. When building, I did check the oil galleries etc, and all did appear well.
This block wasnt actually brand new, but is a customers rebuilt short block, that I purchased fully rebuilt, but un-used from a forum member, built by a reputable builder.

So I dont doubt anyones work....

frito1

iTrader: (12)

Pressure, simply put, is a restriction to flow. It sounds like the pump is pumping fine. You just need to find the missing restriction. Should you double check on the barbell in the back of the block? Pull it out and make sure everything is OK there.