Trying to free a stuck engine

[NHRalph]

I'm hoping someone can me any ideas on freeing a stuck engine on my Honda 305 Dream. I've sprayed PB blaster in each spark plug hole for a few days. I think I can get it unstuck if I could put some leverage on the crankshaft. I didn't want to use the kick start but after taking off the covers, to see if I could place a breaker bar and socket a the crankshaft bolt, I find there isn't any. Do I have to use the kick-starter or is there some other way to turn the crank, besides tearing the motor apart?

[miles2912]

I have a stuck/seized motor too, and someone suggested that I put it in gear and gently rock back an fourth. I was advised against using the kick starter.

If that doesn't work, the motor will have to come apart.

[bbap]

I freed up my motor last month after a 18 year sleep. I pb blastered it for a week and nothing. I removed the heads and put downward pressure on the pistons. It took a fair amount of pressure to free it up. Once free, your gonna want to at least clean the piston ring seats and probably replace the rings. A hone will be in order and a complete inspection.

You will want to inspect the bore for sure. I'd suggest engine removal - it's not a difficult job.

Steve

[Dana01]

Hi Miles & NHRalph,

Welcome!

If the motors are seized, and even if you can get it to rotate, you really don't want to run a previously seized motor with the rusty (seized) surfaces anyway. Cleaning of the cylinder walls and an inspection, ring replacement, and piston cleanup are a minimum.

Sorry guys, I don't see a shortcut. Mother nature had her way and her remains need to be exorcised.

Because of the motor being a stressed frame member, removal is much simpler than a bike with a cradle frame.

IMHO

[conbs]

Somewhere on this site is a post comparing different penetrating oils. The very best was a mix 1:1 of acetone and Automatic Transmission Fluid. Probably worth a try in your situation. Some guys say it it can take weeks to get the motor to free up. Be patient.

I agree with Dana that you probably want to take the motor apart to check the real condition of things even if you do get it to break loose. Another thought is, if you can get it to run and its not smoking and has good compression, then why take it apart? You will get more riding miles sooner with the latter, and you can shake down the whole bike for trnasmission troubles, etc. Both make sense in some ways. You just gain knowledge differently.

If you do take the head off to put pressure on the pistons, just be sure that the crank is not at the bottom of stroke. If it is, the piston won't move and you could damage your crank/rods. Rocking back and forth in gear will avoid that problem.

Good luck and keep everyone posted.

[NHRalph]

Thanks everyone. I decided to take your advice and rebuild the motor. I took the engine out and getting it ready for the bench. While waiting for parts, I'll sand down the frame and re-paint.

[miles2912]

Thanks everyone. I decided to take your advice and rebuild the motor. I took the engine out and getting it ready for the bench. While waiting for parts, I'll sand down the frame and re-paint.

What parts are you going to order? I will have to get (obviously) replacement gaskets. A complete replacement screw set would be nice too.