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3800 rear main seal cover plate gasket orientation

Lou and Blue

Lou and Blue

New member
This is my first post in this forum. I am being told that I must have installed my rear cover plate gasket on backwards because I removed and reinstalled the rear cover plate to change the main seal, and I am only getting oil to the lifter bank on the alternator side . The lifters (and hence rockers) on the ac compressor side are dry.
Can anyone post pics if how the gasket should be installed?


1996 series 2 from a bonneville
Thank you guys !

Louis
 


dont think the back cover gasket can stop oil from getting to 1/2 the engine.

are you just cranking the engine waiting for oil to show up out the push rods? do you have a oil pressure gauge hooked up? if are you showing o/p when cranking it?
 
You can't install the gasket incorrectly, you could use RTV and end up filling the oil passages. Do not use RTV on anything but the bottom 1.5 inches You would have trouble installing the rear cover incorrectly, it sounds like you did though.

This side faces out


This side is against the engine, that channel on the right side is for oil. Likely that's the issue.
 
if backwards the BS wont get oil iirc oil galley crossover would be connected.... but excessive use of rtv is a fair culprit in my experience. its why I use permatex aviation sealer
 
I have the cover on correctly but ever since I did the rear main seal there has been lifter noise. I didnt hear the motor run before I did the gaskets. When the engine is running and driving its rattling from the rockers on the ac side of the engine. So I removed both valve covers and the alternator side is getting oil and squirting oil from the pushrods but the ac side is completely dry. I have tried motor flush, valve medic, marvel
mystery oil and rislone (which mysteriously silenced the tapping noise temporarily) and then I did an acetone flush (2q40w oil ,2 q ATF, and 1q acetone. And it didnt stop the tapping sound. Here's a link to what's been happening.

http://www.fiero.nl/forum/Forum2/HTML/136554.html

I didn't use any rtv on the cover , just the gasket from zzperformance. I am planning on pulling the engine out and separating it from the tranny to replace the rear cover gasket, I am hoping it is on backwards so this oiling issue can be solved.
 


Here the whole story
Ok , sorry but I've been asking around so much . Here's the rundown:
1996 bonneville 3800sc (series 2) - bought the engine with 100k miles on it and I replaced the lim gasket with the zzp aluminum gasket and also did water pump, replaced rear main seal and cover plate gasket, put a 99 Grand Prix oil filter adapter on with the spring and check valve correctly. Also replaced lifters which were primed (soaked over night in oil and pumped before install) And also installed new pushrods. When running the engine I get 60 psi at idle so the oil pump is ok but only the pushrods on the alternator side of the engine are getting oil squirting up and the pushrods on the ac compressor side of the engine are completely dry. I tried motor flush and then rislone and the second drive with rislone the horrible tapping sound silenced and then came right back on the next drive. Thinking I had a clogged oil passage I tried valve medic and marvel Mystery oil but the rattlly tapping is still loud and noisy (no oil to that ac comp side valve train) . So I did a 5-7 mile drive with 2quarts 40weight oil, 2 quarts ATF, and 1 quart acetone. The rattle is still as loud as ever meaning no oil to that side. First I was told I prob have the rear main seal cover plate gasket on backwards preventing oil to that lifter bay.but then I read and see by the gaskets appearance that if that happened it would only be the balance shaft that would be starved oil . Now I am getting info about a dual check valve oil filter adapter that was needed and that that could be starving the ac compr side Lifters oil. I'd rather not have to pull the engine out and take it off the tranny just to find out that the gasket for the rear main seal cover was ok to begin with. Is there such an oil filter adapter with dual check valves? Please help!!! (Oh and thanks for reading this whole thing)
Louis
 
Also, I tried to post this on the 3800pro forum but it wouldn't let me register. If anyone is a member there please post this and anyone who has ideas can email me mrlduet @ yahoo . Com

Thanks guys
 


the only path for oil to get to the front bank from the rear bank oil galley is through that rear block cover.

either you shoved a piece of old gasket into the passage or something else happened.

your yanking the engine any way you look at it
 
and if you want to see even more.. Look up ^^^ on 3800pro by searching on oiling deficencies. It's a slow starting thread...til the plasma cutter comes out
 


Turbocharged400sbc said:
the only path for oil to get to the front bank from the rear bank oil galley is through that rear block cover.

either you shoved a piece of old gasket into the passage or something else happened.

your yanking the engine any way you look at it
Click to expand...
so the ONLY way that the ac compressor side lifters get oil is through the rear cover plate? There's no front oil feed for that side lifters In The timing chain area?


Id rather not have to remove the harmonic balancer and timin chain cover if its not goin to reveal anything or if there's nothing to fix there. It would be less of a job to pull the engine, pull off the tranny and inspect that rear cover plate only.
 
Yup.
Early SII from 95-97.5ish have a rear cover with a shallower crossover groove that caused valve train noise on the early engines so pretty much all 98 and later rear covers have a much deeper crossover path between the two divots which line up with the primary oil galley in the rear bank and the secondary galley which is only for the lifters on the front bank.
that is the only passage it is not like the earlier engines which have drilled crossover path and an integral rear bulkhead that is quite a bit sturdier than the series 2 even if it is heavier
 
Excellent info ! Thank you so much . It HAS to be that coverplate being obstructed. Weird thing is that it silenced with rislone for one drive , anyway I got the rear cover plate gasket in today and the bolts should be in by the end of the week.

If you know where I could buy a 99 or up rear cover plate would that fit my 96 engine? If it would provide more oil passage than it would be helpful. But I bet mine is clogged or it is the gasket being in backwards that's the issue. At least I know I don't have to disassemble the front end timing area and the supercharger and lim and all.
If a newer year cover plate will work and you know where I can source one PLEASE let me know.
Thank you!
 
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