TIMING CHAIN WAY TOO TIGHT !

I'm just getting my old 460 ready to go into my 60 Starliner, and I've run into a problem. This engine originally had a cam bearing failure, and two of the cam bearing bores were at the tolerance limits as a result. I elected to go with roller cam bearings, and had zero problems since. I have since removed the Danny Bee belt drive, and gone to chain, and gears, and this is where my problem started, the chain is so damned tight, that I had to pull the cam gear on with the hold down bolt! Although the engine rotates smoothly, the timing chain is very, very tight. I suspect that when the machine work was done, they moved the center line of the cam away from the center line of the crank. My question is do I dare to run this motor, as the chain will loosen up, or will the roller cam bearings fail? Does anybody have an answer to my problem?

THANKS IN ADVANCE
Wayne (SAWDOFF) Pearce

I would fix it.

Had same problem once I ran it and the chain wore out in two months I returned it under warranty and the replacement fit prefect so it was just a bad chain. Try another chain before you look at the machine work. This was a Zoom brand double roller that I had the issues with.

I should have stated that I did try another chain, and gears - it was just as tight. How do I fix a situation like this without replacing the block, as the cam bores were already opened up for the roller cam bearings?

Wayne (SAWDOFF) Pearce

Put the Danny Bee back on it.

I just might have to do that.

Wayne (SAWDOFF) Pearce

Why did you take it off ?

If the cam tunnel to main bore centerline was changed during the roller cam bearing conversion, you could correct it by moving up to 60 mm cam bearings...requiring another line bore of the cam tunnel. Of course, it also would require a new 60 mm cam too.
That would be a pretty extreme corrective measure and not all blocks will accept the 60 mm bore. It would have to be a really nice block to $$ justify that operation.
If you can't find a chain to work, I would vote for the belt drive.

Keith

Wayne Pearce wrote:I should have stated that I did try another chain, and gears - it was just as tight.  How do I fix a situation like this without replacing the block, as the cam bores were already opened up for the roller cam bearings?

  Wayne (SAWDOFF) Pearce

Maybe ... find a good, used chain...?

rmcomprandy wrote:

Wayne Pearce wrote:I should have stated that I did try another chain, and gears - it was just as tight.  How do I fix a situation like this without replacing the block, as the cam bores were already opened up for the roller cam bearings?

  Wayne (SAWDOFF) Pearce

Maybe ... find a good, used chain...?

Now there is a good plan! I didn't think of that.
I bet there are a few good "experienced " chains around our shops.
Good idea!
Keith

rmcomprandy wrote:

Wayne Pearce wrote:I should have stated that I did try another chain, and gears - it was just as tight.  How do I fix a situation like this without replacing the block, as the cam bores were already opened up for the roller cam bearings?

  Wayne (SAWDOFF) Pearce

Maybe ... find a good, used chain...?

Run it a few laps and the one you have will be 'used'.

I have a double pinned FMS used that you can try and if it works, you can buy it .  

Guy's, thanks to all of you for your responses! I took the Danny Bee off this engine when I retired it from my pro street 50 Ford. The Danny Bee was installed on my new 545 that went into the 50. The 460 was freshened up to be used in my 60 Starliner that will see duty as a cruiser / custom, and I'm trying to keep it as "conventional" as possible. I agree that going to a 60 mm cam bearing could be a solution, but the cost of doing so would make it unfeasible. Trying a used chain is an idea that I honestly didn't think of, I will try that route. Thanks again to all of you for your responses!

Wayne (SAWDOFF) Pearce

I have a nice multi index double roller that I didn't reuse bc it was a tad loose but not bad. It just came out of a running motor so it's not junk. Ill send it to you for shipping cost. I ended up going with another used set that was a little more snug.

Thanks for your offer, I might take you up on that. I want to check my "junk pile" first to see if I have any used ones laying around that I could try. Where are you located?

Wayne (SAWDOFF) Pearce

Wayne Pearce wrote:Thanks for your offer, I might take you up on that.  I want to check my "junk pile" first to see if I have any used ones laying around that I could try.  Where are you located?

  Wayne (SAWDOFF) Pearce

Pm sent

Just curious, how do the roller cam bearings do on a street motor?

I haven't had any problems with them, I've got about 5,000 miles on them - mostly street. Keeping in mind that they're splash fed, I blip the throttle occasionally while in traffic just to keep them wet. They're meant for steel billet cams (rollers), not iron cams (flat tappets).

Wayne (SAWDOFF) Pearce

Well, thanks to the generous offer from "tfsbb466" for a used double roller timing set for the cost of postage, I'm back in business! I pulled the old timing set off, installed the new set, and although it's "used", it fits as a new one should! Thanks again Joe, you've helped me a lot!

Wayne (SAWDOFF) Pearce

No problem glad it worked out bud

That's good stuff right there!!!!  That's why I like this site.  Good group of guys!!!!