Q: blow by around pcv and around oil breather cap.

asked by on

I have a 1983 5.0 convertable H.O 302 with 289 heads and chevy valves erson roller rockers re-grind cam a little one no big jump in cam. i did not rebuild the motor. New high volume oil pump. I am gettig blow by around my pcv valve and my oil breather/fill cap.I know my valves are out of adjustment can this cause blow by. Is the alternative possible cause bad rings? is there other reasons for blow by such as vaccume leaks or timing or anything besides rebuilding it
My car has a manual transmission.

Hi there. Engine blow-by is the result of combustion gasses getting past the piston and/or piston compression rings, this builds crankcase pressure. The PCV (positive crankcase ventilation) valve system is designed to remove the pressure and recirculate the gasses back into the intake manifold. When the blow-by overcomes the PCV system, evidence will be seen at the PCV, oil cap, and KV breather filter. Excessive blow-by generally is an indication of worn cylinder walls and/or piston rings. The modifications to the upper engine and improperly adjusted valves are probably enhancing the blow-by. I recommend having your vehicle’s engine blow-by be diagnosed and repaired by a certified technician, such as one from YourMechanic.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. blow by around pcv and around oil breather cap.

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: I'm getting power to distributor coil, but I'm not getting power to the spark plugs.

Hi there. Check the spark plugs with a spark adapter tool to see if there is a park induced from the coil. If there is no spark, then the spark plug wires could be burned and need replaced. If the...

Q: Q: Ignition sticking.

The key lock solenoid in the grounded shifter will cause the key to stick in the ignition. Most common cause is that the car is not all the way in park. There is a round piece near the base of...

Q: Should I leave the same inner and outer race that came on my new rotors and not replacing it with the new ones that came with my n

If you have a new rotor with new races already installed then there is no need to change them out.

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.