I'm puzzled here, when I attempt to set the timing of the cams, I end up with an overtightened cam chain. It seems like I can't get enough slack, even with the cam chain tensioner removed. The chain is so taught that it's diffcult to install the intake cam. For some reason, initally this was not a problem, but then I realized that I couldn't get the cam chain guide into place, so I removed the cams, installed the guide, and started again, but this time I couldn't get any play in the chain. I then removed the chain guide to see if maybe I had put it in wrong, but no difference. Chain seems to have about the play it should have with the tensioner in place. If I install the tensioner, the chain gets really tight (no play).
I haven't turned over the motor or anything, so I don't think anything is bent or broken.
I reread Rashad's Saga, but I still don't understand how to resolve this.
Adam R
I'm not an expert (although I'm getting plenty of practise ;) ) but I read in my Haynes manual that if you let the chain go slack in the crankcase when installing it then it can bind and maybe cause the problems you are having.
Maybe some one else will know better though.
If the chain is bound, which seems possible since I did drop it into the well, how do I unbind it?
Remove both cams and then let both sides have a little slack and then spread the ends as far as the chain tunnel allows. Now look down the "hell hole" and make sure that the chain is centered on the crankshaft's sprocket. Evenly pull up on the chain until it is tight around the bottom the crank. While keeping tension on the chain, slip both cams thru the chain and then into thier holders. Then slip the chain guide down and into its slot. There should be enough slack to be able to pick one of the cams up and remove it, but don't let the chain go slack without both cams in it, otherwise it will slip off the crank again.
BTW- don't try to turn the engine over , even by hand, until you fix that or you could do some expensive damage!
James, I think the chain is centered on the crank sprocket, but I don't have very much slack. Even without the cams installed, the chain just barely stretches from one end of the well to the other (if I just hold in place with my hands). With the chain on the cam sprockets, the tension would definitely be too much
If it went together and worked before, it will go back together again.
Did you take the head or cylinders off? Make sure both cam guides are out of the way.
Other than making sure that the chain is seated around the crank, I can't think of anything else that would make a chain suddenly too short...
:?
I took off the head, not the cylinders. I think the chain is lined up on the crank sprocket, but it's hard to see because of the tensioner guide - should I have this out?
Yes you can take the top/rear guide out to line up the chain.
While holding the chain with it wrapped around one hand and pulled up as far as it goes. If you have to pull on it a bit to get the links to unkink. It should lay flat againt both guides.
There is a chain guide that gets held between the cases. You may not have gotten that one positioned correctly when you reassembled the top end.
I think one or the other is not positioned right and that is what is causing your problem.
Well, I took the head off again to see if I could get more play in the chain, and I can not. Now I can see the sprocket, and it looks like the chain is on the sprocket ok. I jiggled the chain extensively, then pulled it taught in order to break lose any kinks, and the sprocket appears to move the pistons without any hitches.
Is there any way to access the crankshaft sprocket without doing something drastic, like splitting the cases?
Also, according to Bob Broussard's instruction, the timing mark should put the dash of the RT at the mark on the forward ignition pickup and this is Top Dead Center for the right piston. Yet when I do it, it seems that the piston is all the way down in the cylinder (Botton Dead Center). Am I missing something obvious?
Thanks,
Adam :?
The foreward facing ignition pickup, which is the rear one. Just did mine yesterday and that confused me for a few minutes.
Not to sound stupid, but i didnt read where you had the Cam chain tensioner removed(maybe i missed it)? no i wont assume you have already done this. but this would do just what you describe thus.