429 caddy with crank case pressure

I rebuilt a 429 caddy for a customer 2 years ago. They just got it running a week or so ago. Motor has alot of blowby just off idle. I did a compression test 155-165 on all cylinders. I'm stumped. I think their might be something wrong with the pcv system. I haven't seen the car yet just trying to help the customer over the phone. He has installed a new pcv in it and the problem is still the same.


You give the motor a 1/4 throttle and oil comes out the oil fill tube very bad. I'm open to any and all ideas

Thanks

 

1. Talk to these guys:
http://autos.groups.yahoo.com/group/Cadillac_6364_club/

2. Talk to Chris at http://www.cad500parts.com

 

I'm just really glad you didn't say P-V-C.

 

It sounds like the engine has excessive blowby and the PCV system can't keep up with it.

 

Is the pcv hose collapsed under vacuum.

Tig.

 

Was the engine up to normal operating temperature? Could be condensation evaporating after being stored for so long.

 

nofin, condensation would be water or steam, he said it's oil coming out the filler tube.

Doug, I wouldn't jump to conclusions until you actually see the car. They may have simply overfilled the crankcase, or maybe has a bad fuel pump on it and the crankcase is full of 2-stroke mix, etc.

 

Yeah, I take your point. I just thought that it might be possible that, after two years, the condensation might have built up a little, and on start up mixed with the oil to form that oily **** that comes out the breather intake on engines that don't warm up enough.

 

When did you do the compression test?

 

1st thing is to check the oil level, could be extra gas as above or if it is an automatic and over full, could be the Vacuum Modulator, I had one blow one time and it drained the automatic via the vacuum line from the modulator, sure cleaned up the motor, but not the recomended way
Just another thought
Bob

 

Thanks for everyones help. I had the customer do a leakage test and it p***ed with flying colors. Worst cylinder was 11%.
I had him change oil and filter and make sure he only put 5 quarts in it.
Findly we took the oil fill cap off and I installed a rubber plug over the hole and sealed it off with a hose clamp. It quit blowing raw oil out and the dipstick doesn't move and there isn't anymore blowby.

I think there is a baffle missing in the oil fill tube.


Thanks again for everyones help.

 

If the engine has excessive blow-by then it has excessive blow-by. Capping the oil fill cap wouldn't change that. A piece of this puzzle is missing, but glad your problem seems to be cured.