engine blowby

mike1969 · Post by **mike1969** » Thu Oct 14, 2010 3:06 pm

Thanks Davo,If I only had intelligence to go with it! LOL!

teazer · Post by **teazer** » Thu Oct 14, 2010 3:51 pm

If I understood all of this correctly, the bores were honed and new rings were fitted and after a short blast it leaks again.

Q1 - were the rings installed upside down or the right way up?

Q2 - has it been heat cycled or run in to mate the new rings to the bores?

Q3 - did you use synthetic oil on assembly or to fill the sump?

A 360 degree twin will always push hot oil gas out of the oil drain plug. As both pistons drop, they compress the crankcase gases to about 20 - 30 PSI and that forces oil out the breather

The oil separator plate should have the holes towards the front of the motor to allow oil to drain. If they are at the rear, oil will build up and may block the breather pipe or will be expelled from the breather. It takes a few miles for that to start.

mike1969 · Post by **mike1969** » Thu Oct 14, 2010 5:29 pm

Teazer,
Rings where correct.Checked several times!

Did lots of heating, cooling rides etc.

Used motor oil for assembly.

The information about the oil separator drain holes really clears things up for me.
lm and Davo told me to make sure I had them right but I didn't have a clear idea what the holes were for. I though they were just vents.

Like you said it took several miles for the engine to start blowing oil.

Looks like I may just have it licked this time.

Thanks,Mike

Hotshoe · Post by **Hotshoe** » Thu Oct 14, 2010 7:17 pm

Maestro Ed does it again!

mike1969 · Post by **mike1969** » Sun Oct 17, 2010 2:43 pm

Took the Dream for a 25 mi. ride this morning.

IT'S FIIIIIIIIIIIIIIIXED!!!!!!

Thanks Loudmouse and Davomoto! You guys nailed it!

Thanks to everyone else who gave me advice about getting the cylinders honed and the rings put in their proper position,that probably would have given me problems later anyway.

Mike