Topic: CL 350 Seized 1970

[Joe Lawrence]

   Picked up a nice unmolested CL 350 a while back except the engine engine was seized.  So I been playing with it a little trying unseize it.  NO LUCK!.   

    I have poured a few of the usual fluids in with no results.  In fact  the fluid is disappearing out of the cylinders overnight or faster!.  So I was starting to wonder about may be a hole(s) in the piston(s)....but unlikely therer'd be holes in both pistons??  Then i started wondering about may be the top end was seized.

   So a while back I was talking to a Honda MC mechanic who put in 13 years working on 60's and 70's Hondas and he says he saw quite a many 350s with seized top ends because either oil was allowed to get too low or oil passages were clogged up and top end seized first because the cam shaft bearing set up was crap and tended to give out easy.  Something about the bearings units being  brass and not holding up well with a steel shaft

  This guy says it an easy fix (i guess if you're a Honda Mechanic) to replace the bearings and clean off the shaft with some acid.

   Anyone got any experience with this situation.....or.........could i have seizure for other reasons?  Could it really be the pistons even tho the penetrating oil seems to disappear right out of BOTH  cylinders.  I have tried a littel heat......but nothing.

    Any shortcuts to access that camshaft or see if theres any yellowing of the brass or steel which would indicate seizure?

   TY

[chickenman_26]

The cam bearings are just aluminum bores in each end cap. They get galled and worn from infrequent oil changes, but I've never seen one seize. The cylinders and pistons could seize if they got moisture in them and sat for a long time. Or if the cam chain broke at high rpm, you could have a valve firmly embedded in a piston crown or the broken chain wrapped around the crank sprocket, locking up the crankshaft. My hunch is you're not going to get this bike back on the road by pouring magic elixirs into the cylinders. Time to yank the engine, and strip it down for repair.

Stu