Leaking oil after rebuilt shortblock
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Just installed a rebuilt shortblock, had the heads cleaned up etc. At any rate it's leaking oil pretty bad at where the engine joins to the bellhousing on the transmission. I originally forgot the gaskets for the steam or air tube on the front of the engine and I fixed that. But I'm wondering if the rear block off air tube things are leaking coolant down the back of the block and into the flywheel and mixing with the black stuff and dripping out the bottom. Either that or I figure something with the rear main seal. Anyone have ideas on what to check? I'm thinking of taking off the intake manifold and see if I can see anything.
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did you put the pan and back plate on? if so did you make sure they were lined up and not twisted 1 way or another. if that back plate isnt streight to the pan it would leak between the pan and the block. thats the first think that comes to my mind, besides the seal.
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Originally Posted by RDTA
did you put the pan and back plate on? if so did you make sure they were lined up and not twisted 1 way or another. if that back plate isnt streight to the pan it would leak between the pan and the block. thats the first think that comes to my mind, besides the seal.
Is there any way to tell without removing the oil pan?
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There is a little yellow or white plug on the back of the block. I believe plastic. It is some sort of valve I think. Anyhow I was told to make sure that was there with a new short block or it will ****!!!
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Originally Posted by roadrash9r
There is a little yellow or white plug on the back of the block. I believe plastic. It is some sort of valve I think. Anyhow I was told to make sure that was there with a new short block or it will ****!!!
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...there is a freeze plug whole for the oil in the back of the block.... many engine shops leave the plug out...
If this is the case, the tranny has to come out....
If this is the case, the tranny has to come out....
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Originally Posted by nytoy
Any other clues as to where or what it's called?
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Originally Posted by nytoy
You mean the oil pan and the windage tray? Yes they are on and lined up.
Is there any way to tell without removing the oil pan?
Is there any way to tell without removing the oil pan?
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i just had my shortblock rebuilt and i am having the same problem it is leaking were the trany meets the motor its not leaking bad but it leaking we have already replaced the rear main seal once but still the same thing
sorry for treading on your post.
sorry for treading on your post.
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Originally Posted by DrkPhx
Oil galley plug. It's white and looks like a mini-dumbell (for lack of better desc) and inserts in the rear of the block. If this wasn't installed your oil pressure would be very low.
I pulled off the intake manifold and looked and felt around at the top of the back of the block and bellhousing, all clean nothing leaking. It appears at the top where the rear cover is on, it's also clean. I would think that is the rear main is bad that it would fling oil in every direction, rather than just leak to the bottom.
Any other ideas for me and ruck98?
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you have to make sure the front and rear cover are aligned properly or the crank seal will leak like crazy. there is a special tool from gm that cost $600 that is use only for this task and is very important to make sure this is done properly. looks like you will be removing the trans as bad as that sounds. you will also want to put a new crank seal on there since it wasnt lined up right it may have prematurely wore the seal.
brad
brad
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is the $600 GM tool for installing the rear main seal?
or something else?
removing the tranny is a PITA for nytoy because the LS1T56 is stuffed into an FC rx7 and you'd need to tilt the motor a little to get the T56 off the bellhousing... then get the bellhousing off the motor to get at the rear main. and if you need to re-do the oilpan bolts its another PITA because the oilpan is almost touching the steering rack and you cant reach the bolts to torque them properly... grrrrrrr!
dang it, this LS1 might come back out!
or something else?
removing the tranny is a PITA for nytoy because the LS1T56 is stuffed into an FC rx7 and you'd need to tilt the motor a little to get the T56 off the bellhousing... then get the bellhousing off the motor to get at the rear main. and if you need to re-do the oilpan bolts its another PITA because the oilpan is almost touching the steering rack and you cant reach the bolts to torque them properly... grrrrrrr!
dang it, this LS1 might come back out!
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So I'm guessing nothing I can tighten or see before I pull the trans out? What a pain...
Will be painfully obvious which is leaking when the trans is pulled, either the rear main seal or this oil galley plug?
Will be painfully obvious which is leaking when the trans is pulled, either the rear main seal or this oil galley plug?