Honda CB750 Sandcast

The Restoration Shop => Engine Mechanical => Topic started by: Joe K on February 19, 2010, 04:05:38 pm

Title: Engine Smoking Oil from Oil Lines
Post by: Joe K on February 19, 2010, 04:05:38 pm

My motor is now smoking oil out of the top valve cover oil line and top oil reservoir tank oil line. No smoke/oil is coming out of the exhaust pipes. Has anyone experienced this before? I will need to check the timing and do a compression test. I am not sure about the milage. Maybe a piston ring has broke. Any advice will be helpful. I want to do an engine re-build anyway, but later rather than sooner.

Thank you,
Joe

Title: Re: Engine Smoking Oil from Oil Lines
Post by: Joe K on February 19, 2010, 04:05:51 pm

I don't feel any exhaust coming out of #2 pipe. I am starting to think I will need to re-build the motor. Not a big deal. I wanted to do it anyway, now this is the motivation I need.

Joe

Title: Re: Engine Smoking Oil from Oil Lines
Post by: steff750 on February 19, 2010, 04:06:13 pm

i had this problem once with steamy smoke coming from the same engine breather i guessed it was engine back pressure ,new pistons and a rebore cured the problem for me,yours does sound serious might be a piston or rings shot ,you will neeed too strip it at least,

Title: Re: Engine Smoking Oil from Oil Lines
Post by: Joe K on February 19, 2010, 04:06:31 pm

Well I took the engine apart and found that the #2 piston was deteriorated on one corner side. Also, in the #4 cylinder, one of the rings was broke. I am so glad I took the engine apart to do this re-build, because I learned so much about it! It's really not that hard to do either, as long as you use a shop manual and keep the parts in order.

Now I will have a great running, compression motor to ride all year long in beautiful, green (because of all the rain we have had this year) southern California!!  ;) ;) ;)