Thread: 400 SBC problem - Newbe

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Welcome to CHR, Duane! Hope you find what you’re looking for and that you have a nice long stay here. Love those old Healeys. Had a coach in high school that drove a 3000 – black with tan leather and a real wood dash. Sweet little rides.

Blue smoke is never real good. There are typically two causes – one fairly easy to remedy and the other is, as you’ve alluded to, rather costly. I’d start with the breather system. Make sure you have a clean PCV valve and a clean breather on the engine. Typically there is a breather in the valve cover on one side and the PCV valve on the other. Soak them in a non-flammable solvent overnight and see if that helps with your problem.

The oil pressure numbers you mentioned are not atypical for a SBC – especially one with a few miles on it. Do you know what the mileage is in this engine? Have you pulled the plugs and looked at them? 125 is well within specs for a SBC (100-160PSI) so I wouldn’t jump to rings right away. Valve seals could be the culprit and they can be replaced with the engine in the car. It’s an “all-day-sucker” and you need to have a few specialized tools to pressurize each cylinder and compress the springs. It can be a little tricky and it’s easy to destroy the new seal if you’re not real careful. Watch this little video to determine if it’s something you can tackle of if you want to have it done.

https://www.youtube.com/watch?v=OsGqmOQus6Y

The guides could be worn and to properly fix requires pulling the heads and have them knurled or replaced.

A quart every now and then might not be such a bad thing at this point.

Let us know what you decide. Again, welcome to CHR!
Glenn

A puff of blue on starting is usually valve seals or guides. I have had several 400's and they all did it, the local guru said it was a result of the large diameter, short skirt pistons. Pick a story you like, I guess.

Thank you for your great reply and advise. I will be taking the car into the shop the end of September to be checked out. From the sounds of things it might be the valve seals. Thanks again.