Questionhello, just got my first motorcycle, cb360. seems great, but needs minor
tuning here and there which is new for me, but exciting.
one thing that just popped up is an oil leak from the front top of the engine...
under the tappet covers, i think its called the "top head gasket", also where
the tachometer cable goes into the engine, or the tappet covers.
what does this mean? is it really bad news? i dont mind getting my hands
dirty, but is it really complicated to change a head gasket? do i have to
remove the engine? i dont want to wreck it. if it looks like im going to have to
sink tons of $$$ into it, may be better to get rid of it.
do the tappet covers have gaskets/o-rings?
does where the tachometer cable go in have an o-ring?
thanks in advance!
jon
AnswerJon, go to http://www.powersportspro.com/partsfish/login.asp sign up and log in and choose HONDA, then the CJ350 model, the cylinder head cover. That is probably where your leak is, plus the leak at the tach drive seal. This is NOT the head gasket, which is between the cylinder head and the cylinders... below the level of the spark plug.
The engine probably does have to be removed to get the top cover off. You will have to remove the bolts and separate the cover, which is sealed with 3 BOND #4 liquid gasket or something similar. Good time to change out the camshaft seal, while you have it apart. You will need to carefully remove the old gasket material and then clean all surfaces so the new liquid gasket can be applied evenly in a thin coat. Reinstall the cover and torque the bolts down evenly.
It is somewhat more complicated than this brief description, but as long as you don't tamper with the camshaft and cam timing, it isn't that hard of a job to do.
Get a shop manual that covers these machines at www.helminc.com or Ebay sources. Change out the O-rings on the tappet covers, to help ensure a leak proof job. Be sure that the large breather tube coming out of the top cylinder head cover is free to all fumes out. Pinched hoses will aggravate oil leak prone areas.
For a quick and dirty repair, clean the outside area with brake cleaner or contact cleaner, scrub the surface a little with steel wool or scrub pad to make it nice and clean metal, then apply some high temp sealer at the leak area. If the engine isn't putting out a whole lot of crankcase pressure, then the leak should subside.
If you get a small 90 degree scribe tip tool you can probably pry out the old tach seal and install a new one, using a matching diameter deep socket to drive the new seal into place.
Bill Silver www.vintagehonda.com
