Well, here goes. I hope the answer is not too bad. Just installed a 540. Brand new motor. After a good run of 4500 to 5100 there is a gray mixture comming out of one of the breathers. Only happens when I push. Motor has 3 hours on it. There is no water in the oil at all. Is this a intake manifold leak? I have read in previous forums that this can happen. I installed a performer RPM and used the correct gaskets that Edelbrock suggested. I did use sealant around the water pasages and Intake. Would that create a seal problem ???

Sheikman

If I understand you correctly, you are saying that oil colored gray is pumping out of your bretaher when you run the motor hard. I don't know what makes it gray but, if this is the case, then I would suggest you run a leakdown test. It sounds to me like you have exessive blow by through the rings. This causes the crankcase pressure to build up too high and will pump oil out of any hole it can find easiest to do so.

I would talk to some of the motor builders, I have a bit of blow by that after i run is usually around my blow by filter on my valve cover. It is not very much just splattered about the size of a grapefruit. I was concerned and called Keith Eickert and he told me that this was normal and nothing to worry about. How much oil do you have that appears?

With only 3 hours on the motor the rings may not be fully seated yet. While I did not have anything but gray smoke coming out the breathers on my custom built 502, it took about 8 hours before that went away. Now there is no noticeable blowby at all. Just a little black soot on the flame arrester after a few hours.

Im with macdad,,,, unless there was alot of dyno time, I would give some time to seat the rings,,, also would not be running new motor hard yet without alot of dyno time.

Thanks for the help here.
The motor did spend break in time on the dyno.
I'm not sure how much but when purchased I got dyno sheets.
The fluid drips out of the breather hose where it attaches to the carb. The color is grayish white, looks like when there is water in the oil but the pan oil is perfectly okay. There is not a lot, just a small puddle on the intake. I retorqued the intake but still happens. Reminder, I am not making full throttle passes just varying the rpm's. The color is what concerns me here

Sheikman

What is your oil temp? Do you have any condensation under the valve covers? Need to get temp up to 210 deg. The color might be from condensation and will not show in oil pan.




Ed

I don't agree with the break-in idea. While it is true that rings take a little while to seat to their BEST seal, they should not be blowing enough compression past them to pressurize the crankcase and blow oil out of the breathers. In my old drag racing days, the only break in time on my motors was idling them in the garage for a few minutes. The next time it was fired up, it was running at full speed down the track. I never had oil coming out of the breathers due to a fresh motor.

oil temp is around 230.
would a water leak around the exaust header make this happen.
I have EMI Thunder with the long Bravo exaust. The seal does not look like it is leaking on the outside, but maybe on the inside.
Any suggestions

Thanks

I had ALOT of Blow-by and was really worried on my new motor. I had to ditch the v.cover breathers and go back to the hoses. At 10 hours I was getting a tablespoon of oil every hour or so thru them...SLOWLY but surely this has gone down to a very very light film on the arrestor air horn every couple of hours. Ive got almost 35 hours on it now. Ive got Dana rings Moly and Ductile iron........But like you said the color would have me worried. Im betting on the condensation idea......

"Bad-Habit"