Page 1 of 1

Stiff to pull

Posted: Sat Nov 20, 2010 1:59 pm
by outboard
Hi Guys, can I get some of your eperience please?
I've just rebuilt a 40+. What I'm finding, the flywheel is very stiff to pull, so much that the stand moves when I try, any ideas please?
I got it to run for about 5-10 seconds then it stopped, but I could have dirt in the fuel line. If it's anything to go by, I have replaced new rings.

Thanks
Gerard :D

Re: Stiff to pull

Posted: Sat Nov 20, 2010 3:36 pm
by Keith.P
Give it a pull without the spark plug in and if its still a job to pull then somethings no right.

Re: Stiff to pull

Posted: Sat Nov 20, 2010 7:13 pm
by outboard
Alas, it's not right, with the plug out it's still requiring a hard pull to turn the flywheel.
What happened was, the securing wire on the bolts of the piston rod must've had excess which snapped off, got down between the piston and the barrel. There's scratches on the barrel and piston which I've honed down but not exactly got rid of, could this cause my problem? On pulling the cord it sometimes feels like the wheel is catching somewhere and I end up pulling the engine over.

Will take the leg off from under the crankcase and try spinning it. :?:

Re: Stiff to pull

Posted: Sat Nov 20, 2010 7:27 pm
by Charles uk
It could be that the flywheel is rubbing on the ignition coil cheeks.
But without the serial number we won't know if you have that type of ignition.

Re: Stiff to pull

Posted: Sat Nov 20, 2010 7:40 pm
by Horsley-Anarak
I have had two forty plus engines that were stiff to turn over.

In both cases the crank was bent.

Drop the leg off and see if it is any better, if not remove the cylinder and see if the resistance is in the crankcase.

Crankshafts are quite fragile just a little bit of rough handling can bend them.

I now always check the crank on any engine that I take to bits.

H-A

Re: Stiff to pull

Posted: Sat Nov 20, 2010 7:56 pm
by outboard
Thanks H-A. Will respond when I do this, fingers crossed it's not but it could well be. I noticed on my FPC if you lift the flywheel there's a little free movement, however there's none on this baby which might suggest a bent crankshaft. :roll:

Re: Stiff to pull

Posted: Sun Nov 21, 2010 10:29 am
by outboard
Just as an after thought, can the crankshaft be straightend if it is bent, or is it a replacement required?

Re: Stiff to pull

Posted: Sun Nov 21, 2010 10:49 am
by Horsley-Anarak
I have had good success sraightening them.

Have done 6 now, if you can get them within a couple of thou then they spin ok.

You may need to pop a reamer through the crankcase as this may be a little distorted.

bent crank.jpg
H-A

Re: Stiff to pull

Posted: Sun Nov 21, 2010 9:13 pm
by outboard
Thanks guys. Didn't notice the post from Charlesuk, will post the serial number tomorrow, hopefully it is something as simple as rubbing.
Just built another 40+ tonight and with the basics assembled this one seems to be turning ok. Should get the carb on later this week and we'll see if it goes. This was a totally seized baby so if it starts I'll be ecstatic.

Turned my FPC today after sitting for a few months, three pulls and away she went, super! :D

Re: Stiff to pull

Posted: Tue Nov 23, 2010 5:24 pm
by outboard
Engine number FP 2320 B0