Low Oil Pressure on Fresh Rebuild

[atlguyinbama]

I just got finished dropping my built motor into the Laser. I used the Vasoline route to prime the oil pump (new Topline piece), as well as unhooking all injector plugs and coil plug to turn the motor over and prime the system. It started up great and had ok pressure at first, but after warming up the oil pressure light comes on most of the time at idle and the stock guage shows little pressure. As I increase the throttle, or pull the idle up to about 1k rpm the light goes off. Upon the initial test drive, the pressure rose only a little with the rpms (at 3k was about halfway between the bottom mark and the low mark in the "NORMAL" range. Through research, and my own experience I have came up with a few things that could be causing it, but to me, none seem to be enough for that low of oil pressure.

-First, I installed a BS eliminator kit (with stubby for rear shaft), I removed and turned the outer bearing for the front shaft, but had no way to remove the inner and turn it. So I left it alone. This may cause a slight drop, but I cant see it being that much.

-Second, I used 90 filter housing so I could use an oil cooler. The housing has not been used in 2-3 years, so it could be possible that both the diaphrams in both pressure sensors could be dry rotted and split.

-Third, the Oil pressure relief valve could be sticking for the same reasons as above. I have seen on here which bolt it is on 2g housings, but have yet to find a pic of one on a 90 housing.

Right now I am leaning toward the third choice, as neither of the others seem very likely to be that much of an issue. If so, how do I go about fixing this. Can it be cleaned out and reinstalled? Or will I have to go to the dealer to get a new one?

I will be installing a manual oil pressure guage this weekend, and can get an accurate oil pressure then.

Any thoughts would be appreciated.

 

[BIGBLAZE79]

If that inner bearing has an oil hole on it and i"m willing to bet it does. If there is no shaft there then there is no restriction to the oil coming out that hole. I would imagine a large internal oil leak. Not sure with your engine but I would start there That's some scary sh1t man I wouldn't risk the new motor till I figured it out. Good luck!

 

[atlguyinbama]

From what I read on VFAQ it is optional to block off these holes. It states it will lower oil pressure a "little". With only one oiling hole open, I just dont think it could drop pressure that much. Or am I just way off?

 

[->PrOjEcTGS<-]

Way off. It is optional if you are leaving the front shaft in there. Since you pulled the shaft, you NEED to block off both oil passages. With the shaft out you are creating an internal oil leak as he stated above. The equivalent of drilling a 1/4" hole into the case of your oil pump. Sorry, but you need to pull that bearing out and turn it to block off the oil passage. The reason you don't have to do it to the rear shaft is that it gets it's oil supply through the shaft rather than the block.

Just take the oil Balance Shaft and use the edge of it to pound out the old bearing. Then use the shaft to pound it back in. It's super easy. Just time consuming seeing as you already have the engine in the car. Good Luck

 

[atlguyinbama]

Is there any way of doing it without pulling the front cover back off? or am I just screwed and have to pull it back apart?

 

[->PrOjEcTGS<-]

Yea you're pretty much screwed! You've got to pull the front case off. That's the crappy part about not doing it right the first time!!

Live and learn!

I've done similar things like that with my transmission. I swapped in one without swapping my shims from behind the pivot ball over. DOH! I got it all in and then 10 minutes later had to pull the tranny back out the just to put a couple washers behind the pivot ball.

If it were me. I would just pull the engine back out, put it on a stand that way you can make sure all of your gaskets have a good bond with sealant when you put it all back together. Remember you have to pull the oil pan also which means you're gonna have to reseal that also along with your turbo's drain tube. Plus you would have a lot more room to work on it from outside the car.

BTW, don't even think about driving it around without doing this work to the engine. When that oil light comes on it pretty much means there is NO pressure. DO NOT DRIVE IT!! You've been warned. I don't want to see a thread by you in a couple days saying that your brand new built motor spun a bearing and wondering why...

It won't take you that long to get it out and then back in. One day out, pull the pan, timing belt, front case, turn bearing, reseal all your gaskets. Next day put it back in. Make sure you don't get some shavings in the engine. When I did mine the hardened balance shaft makes nice marks in the bearings while pounding them out and might have a tendancy to create shavings of metal since they are made of softer metal. You DON'T want these shavings to get into your new main/rod bearings.

If you start tonight you will be done with it tomorrow!

Goodluck!

 

[DSM1G90]

..and when you put it all back together, screw the vasoline trick, this link below works tons better to prime the system up

http://www.dsmtuners.com/forums/ar...ump-timing-components-already-installed.html

[that is actually separate from the filter housing itself, that uses coolant to cool the oil. IMHO a pretty stupid design, but used by almost all major automotive manufacturers

... there is a mod where one can lock that fitting inside so it won't turn loose causing the oil pressure problems this design had, and this mod was to drill and put a setscrew in that fitting so it wouldn't turn loose...and it's below:

http://www.dsmtuners.com/forums/art...917-oil-filter-fix-water-cooled-housings.html

-DSM

 

[atlguyinbama]

I wasn't refering to the design of the spin on bolt in the middle, i was refering to the poor design and materials used that can cause the sandwich plate to crush and leak coolant into the oil or vice-versa, and the fact that using 180+ degree coolant to cool oil is not the best design out there, yet is better than nothing. The 90 oil cooler design is much more efficient and cools the oil much better.
Sorry if I worded the original post where that was confusing to some.

Thanks guys.

be careful when pressing the bearing back in. i split mine apart pressing the back one in. just make sure it goes in straight and use oil to lube.