Engine hard to turn, advice before I proceed

[doctorgonzo]

Ok, finally got a chance to get back to my engine this morning. Had to pull the cams back off because I forgot to put shims in before I installed (broke a journal cap bolt in the process, just gonna run it with 3 on that one for now, and heli-coil next time I adjust valves). The larger problem is this, as I started getting ready to check the shims (put all 2.60 and 2.55 in there), and as I'm turning the engine it rotates about 1/4 turn (turning clockwise from the right side) and becomes basically impossible to turn. Manual tensioner is loosened, but the cam chain has become very tight. I'm not using a huge wrench, so not a ton of leverage, but it seems stuck. I don't want to Conan the thing and maybe snap the cam chain or do other damage. Any ideas on how to proceed? I am hesitant to pull the cams again and risk another journal cap bolt.

[gearhead13]

Double check that your cams are timed correctly. could be valve to piston contact.

[doctorgonzo]

Double check that your cams are timed correctly. could be valve to piston contact.

Pretty sure they are, it may come to that though. As the engine won't turn I'd have to pull the cams to do it, basically just start over. That's last resort.

[Nessism]

Sounds like the pistons are hitting the valves. Proceed with caution. I'd snug down that tensioner and then check the cam timing. Oh, and fix that broken bolt now, don't wait. Many times the nub will spin right out of the head when the bolts break off. Best to do the job right.

[hampshirehog]

Either the valves are touching - check the timing - it's the T on 1-4 if you need reminding (I always do) or you've got a jam in the bottom end; maybe the cam chain has got wrapped up on the bottom sprocket or you've missed the bottom locator for the front cam chain guide.

Or, of course, the bike could be in gear?

And as Ed suggests, sort that broken bolt out - all that work you've been doing could go pear shaped for the sake of a happ'orth.

[chef1366]

Take off the cam chain tensioner and the intake cam and reinstall the cam first and before tightening it all the way down install the tensioner. I bet you cam chain is bound

[Nessism]

The Suzuki manual shows use of a pair of vice grips to clamp down on the cams before tightening up the caps. This method works great; after using it I was wondering what took me so long. Puts much less stress on the cam cap thread too.

[psyguy]

i put my money on a jammed camchain

[doctorgonzo]

Thanks guys. gonna pull off the intake side, and give it a try, hopefully bound cam chain. I guess I will go ahead and fix the broken bolt, those are a weird size so bet I have to order the heli-coil.

[gearhead13]

Why do you need a heli-coil if you broke the bolt? extract the rest of the bolt, get a new bolt and GET A TORQUE WRENCH!

[chef1366]

Thanks guys. gonna pull off the intake side, and give it a try, hopefully bound cam chain. I guess I will go ahead and fix the broken bolt, those are a weird size so bet I have to order the heli-coil.

Those are a #6 metric. They should be at your local auto parts shack.

[doctorgonzo]

Those are a #6 metric. They should be at your local auto parts shack.

I actually thought about it last night, and it's not stripped, it has a broken off bolt in it (down in it, doesn't stick up beyond the hole at all in fact recessed a bit) so I guess first step is to try and drill/tap. I have been needing a good excuse to buy a set of metric taps and dies anyway.

[doctorgonzo]

One more question....

Never tapped one before, only drilled out to heli-coil. I know I will need to be very careful on depth. I can figure that out from comparing the broken off top of the bolt with an unbroken one, but how big a drill bit should I use? It takes a 7mm x 1.0 bolt. So I should drill it out with a 7mm bit then tap it?

[errorcauser]

Never tapped one before, only drilled out to heli-coil. I know I will need to be very careful on depth. I can figure that out from comparing the broken off top of the bolt with an unbroken one, but how big a drill bit should I use? It takes a 7mm x 1.0 bolt. So I should drill it out with a 7mm bit then tap it?

You'll want your drill bit to be smaller than the tap size you plan to use. The tap that i bought for my exhaust bolts had the drill bit size wrote on the pack that the tap came in.

[doctorgonzo]

You'll want your drill bit to be smaller than the tap size you plan to use. The tap that i bought for my exhaust bolts had the drill bit size wrote on the pack that the tap came in.

I thought so, I guess 6mm, or 6mm and change. Worried a bit about staying straight with no drill press (and not wanting to pull head even if I had one), but gonna go for it.