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Boost Leak and Compression Test findings

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duck95

15+ Year Contributor
73
0
Feb 23, 2006
Pittsburg, California
I've read and searched, found many things that relate to my situation, but want to get an official blessing from the wisemen. I recently did a boost leak check starting on the TB. From there I get pressure build up, about 10psi and then it slowly leaks down. I open my oil cap up and then there is a rush of air that comes out. I've got everything plugged and checked my pcv for leakage. So I've got leakage either through my valve seals or piston rings. I've got 123k on the engine. Also, when the engine is running, I took off the hoses that connect the pcv and the breather. Air is only coming out of the breather hose, so I took the pcv off. Air is coming out of where the pcv was, so I cleaned and checked the pcv. No problems with it. But I put it back in and no air. I figure the air is taking the path of least resistance and coming out the breather hose, that's why I have oil in my tb elbow. Sound correct so far? So then I did a compression check. Here are my results before and then after a cap of oil.
#1 #2 #3 #4
170 155 180 160
190 190 200 190

All cylinders except #3 built pressure up slowly. These results show me I've got an old motor that probably needs to be rebuilt. Any tips on how to keep her limping along with additives or other elixirs? I've got a line on a 6bolt but it's going to be a while till I get it built (looking at going with a stroker!), so I just want to her to run well. I'm pushing 11psi right now on a rebuilt 14b.
 
The numbers do look a little under. You can drive and try some additives if you like to try to help your compression. BG makes good products. I wouldn't worry about rebuilding the 7 bolt if you can get a 6 bolt. I would drive till it fell apart. I wouldn't turn the boost up anymore. If this is your only car I would recomend take it easily till the 6 bolt was readly to put in.
 
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