Engine is not seized, but wont go past tdc

jba6555 · Post by **jba6555** » Thu Nov 06, 2008 3:36 pm

I have recently started working on a 1964 CA77. I bought the motorcycle a few months ago and drove it home. I have been slowly working on fixing some of the little things, rebuild the petcock, clean the tank, rebuild the carb etc. After putting the carb back on the bike I tried kick starting it for 5 minutes, with no luck (I had the key in the wrong position) 3 days later (after i realized the key was in the wrong position) I went back out to try to start it. Now I can not get the engine to turn passed top dead center. Using the rear wheel I can rock the engine back and forth, but I cant get it to turn past tdc with the kickstart or by push start.

A second problem, when i turn the key into the on position I can hear a humming noise.

downtoscratch · Post by **downtoscratch** » Thu Nov 06, 2008 4:36 pm

Can't wait for the "Paul Harvey".... rest of the story on this one! Nothing mentioned would seem
to show a logical link from one event to the next. Sorry I can't help. Please do follow up with the
solution once arrived at. dts

Greggie-e · Post by **Greggie-e** » Fri Nov 07, 2008 1:26 am

did you replace the spark plug?

if you put a plug with a longer reach in the piston will hit it and not go past TDC.
This is the easiest solution to your problem and should be checked.

The humming may be the indicator mechanism if you have one.

If not it may be a weak short in the horn.

Try disconnecting the horn forst as that is the simplest solution.

deaddog · Post by **deaddog** » Fri Nov 07, 2008 8:51 am

Possibly hydro locked. Did you leave the fuel on? Pull the spark plug and see if it turns over.

jba6555 · Post by **jba6555** » Fri Nov 07, 2008 6:22 pm

The cylinders are clean, I took the plugs out to make sure i was getting to top dead center. And there is no fuel in system. I have taken the electric starter off to just to make sure there was no snagging there. I put a wrench on the crank and I can turn it almost to TDC, and i can rotate it backwards almost to TDC but it just wont go past TDC (I have like 350 degrees of rotation)

I am beginning to think I have a valve stuck open. Has anyone else had a sticky valve? is there any easy way to tell if/which valve is sticking? I would really prefer not to have to drop the engine. Has anyone had the Cam Chain jump a tooth to get the mechanical timing off? I am just trying to think of anything that would cause a valve to hit the piston.

I guess it could be something on the lower end of the motor too. I don't really know what the crank would get stuck on.

LOUD MOUSE · Post by **LOUD MOUSE** » Fri Nov 07, 2008 8:52 pm

Remove the tappet adjuster covers and see if it will turn over. .........lm

jba6555 wrote:The cylinders are clean, I took the plugs out to make sure i was getting to top dead center. And there is no fuel in system. I have taken the electric starter off to just to make sure there was no snagging there. I put a wrench on the crank and I can turn it almost to TDC, and i can rotate it backwards almost to TDC but it just wont go past TDC (I have like 350 degrees of rotation)

I am beginning to think I have a valve stuck open. Has anyone else had a sticky valve? is there any easy way to tell if/which valve is sticking? I would really prefer not to have to drop the engine. Has anyone had the Cam Chain jump a tooth to get the mechanical timing off? I am just trying to think of anything that would cause a valve to hit the piston.

I guess it could be something on the lower end of the motor too. I don't really know what the crank would get stuck on.

305 · Post by **305** » Sat Nov 08, 2008 3:53 pm

when you had the carb off for rebuilding , is it possible something fell inside...???