Hey guys I just recently blew something in my B20B. I thought I had blown the motor but I may be wrong. I removed the head to find puddles of coolant on top of the pistons, so immediately right there I knew I blew at least the head gasket.

My question is, is there any to check if my bottom end is still good without removing the pistons? My head is off at the moment. Should I just buy a new head gasket and see if it runs fine afterwards? I'd pull the pistons out, but then even if they're good I'd have to get at least new rings, then have my mechanic put them back in because I don't trust myself doing that.

I heard something about putting air into the cylinders to see if smoke comes out of where you put the dip stick in. How can I do this? Just spin the crank?

On another note, I did a compression test before pulling the head and it was 85 accross the board. It should be around 170, but can each cylinder 'break' evenly? Another reason to believe it was the head gasket. Also, last time I blew my motor the one cylinder that was bad was tested at 30.

ALSO, when it happened there was some smoke coming from under the intake manifold. I couldn't tell from where exactly because it was pitch black out. The car wouldn't start up after that unless I gave it a little bit of gas. I didn't really try to start it afterwards though.

Last time I blew a motor it made a god awful "PSSSHHH" sound while I was nailing it, this time the car run until I parked, then it just stalled out.

This all happened due to overboosting one time. Sorry about the long post. I was banned under my other name due to my idiot friends, and I can only post 5 times within 24 hours under this name so I figured I'd lay it all out.

Any and all help is very much appreciated.

 

 

Sounds like your head gasket. This is what I would do IF I did not wanna pull the pan and pop the pistons out:
First thing I would do is take some oil and pour around the pistons. Then turn it over by hand while watching the oil on the sides. I always do this when building a motor because it is a great way to see if your rings are in. If you spin it fast while your watching the oil willpush all the way up then when the pistons goes down fast you should see a couple small trails were the oil goes through the ring gaps. If there is more than 2 very very small trails in each cylinder you have ring problems. Next thing check your cylinder walls for cracks. B20 have a problem with this.
if that all looks good replace the head gasket. I usually use 1000 grit sand paper to clean the surfaces. Either check the head for warpage or have it checked by a machine shop. If that checks out swap the head back on and run it. If you have blow by IE piston or ring problems you will be able to tell by the amount of smoke and pressure coming out of the dipstick hole and the top breather on the valve cover.
BTW if your boosting this motor you have detonation problems. Detonation is an explosion of you air and fuel before it is supposed to explode, so instead of sending your piston downwards like it is supposed to it is pushing your head off the block and your pistons and rods out the bottom. The head gasket is the weakest part of this chain but it wears on everything. Head gasket, wrist pins, rod bearing. Everything. Sends shock through your whole motor. Even if your not boosting you have detonation problems. If it does run after this, fix the problem or next time you won't be so lucky.

 

Hey thanks for the input, I really appreciate it. I got your IM but can't respond to it because of this Trial member status.

How much oil should I put on the pistons? Where exactly should I put it?

My car was boosting a safe 6psi until I had a shop do my downpipe/intercooler pipe and I think they broke my wastegate, so I overboosted. That's a whole other story though.

 

just enough to cover the top of the pistons.