Hi-

What do various degree of blowby indicate? Blowby is any excess gas, smoke, oil being blown out through the oil filler cap when the engine is running, correct?

Is it combustion gasses blowing through the valve seals, or also coming through the piston rings at the bottom?

No blowby at all would indicate what?

Thanks!
-Aaron

Blowby is caused by damaged rings. The more blowby you have, the less compression the engine has, which results in less power, difficult starting, rough idle, and increased oil consumption.

No blowby at all means that the piston rings are in very good shape.

Excellent! So then the 300D that has absolutely no blowby would be in great shape (as far as the pistons are concerned)? Awesome.

Thanks!

How do you keep the piston rings in good shape to avoid blowbys and oil consumption?

My 300D has some blowbys and some oil consumption.


Thank you

Use a good synthetic oil such as RedLine 15w-40 Diesel Oil, or Mobil Delvac 1 (hard to find, but arguably the best diesel oil on the market).

Looks line another oil thread to me.....

Yep, good oil and change it regularly.

Have a great day,
Change oil hot and change oil often.

Uhhh... NOT!

Someone asks for a recommendation, I give it. Take it with a grain of salt.

I only use 30% Peanut Oil / 5% Sesame Oil / 65% Safflower oil. When I change my oil, I put the stuff from the pan on my salad.

Also, making sure the air that is getting to the cylinders is free of anything but air, i.e., dirt from cracked or improperly installed air tubes, crappy or old air filters, dislodged junk from EGR residue build-up in the intake manifold, etc.