Too Tight Cam Chain

Hi Guys,

I am finally making some progress on the rebuild. I got to the point of putting the cams back in today, when putting the inlet cam in (after the exhaust)the cam chain is super tight. I had to push hard to get the cam in and depress a valve, thought this would give me slack. Nope, I got it in, but when I say tight, I mean it - no slack what so ever. I checked the length of the new vs. old chain before installation, it is about a half link shortrd (I though due to 42000 miles of use), certainly not enough to make it this tight.

Going with a manual tensioner, which isn't installed, so not that. Any ideas? Photos below.

Cheers Guys,

Brendan.

if its a MKII engine.....124 link chain???? double check the chain link number......is the chain aroung the crank correctly??? if not it will not fit correctly....can be really tricky to get chain to fit around smallish sprocket. If not a MKII engine....you should be using 30 tooth cam sprockets...are you using incorrect 32 tooth sprockets. Really dont know what you did so am throwing everything at ya.

Like 4thekz1000 said i would check all that. Make sure you got the chain on the crank sprocket correctly. By telling us what you have done to the motor also might help us.

BB wrote: Hi Guys,

I am finally making some progress on the rebuild. I got to the point of putting the cams back in today, when putting the inlet cam in (after the exhaust)the cam chain is super tight. I had to push hard to get the cam in and depress a valve, thought this would give me slack. Nope, I got it in, but when I say tight, I mean it - no slack what so ever. I checked the length of the new vs. old chain before installation, it is about a half link shortrd (I though due to 42000 miles of use), certainly not enough to make it this tight.

Going with a manual tensioner, which isn't installed, so not that. Any ideas? Photos below.

Cheers Guys,

Brendan.

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If those pics are with 1 & 4 at TDC, it's pretty easy to see your intake cam is late.

The obvious question is, do you have the cam chain tentioner loose?

Take the tensioner right out of the block when you install the cams.

1] The chain might not be on the crank sprocket correctly.
2] You are probably 1 pin off on the Intake cam's timing.

Don't include the pin that aligns with the exhaust index mark in your pin count. Start with the one above it as the first pin in the 28 pin count.

He stated that the tensioner is not installed so can't be that.
If it's not a miss match of crank/cam sprockets or wrong camchain in a mk2 then it can only be the camchain sitting to the side of the the teeth on the crank or bunched in the main bearing cap.
Rotate the engine slowly whilst pulling on the chain to release the bunched links.
This seems more probable as even with the chain not sitting on the crank teeth there is usually plenty of slack to get the cams in easily and that problem is usually only discovered when rotating the engine to double check the timing.

zed1015 wrote: He stated that the tensioner is not installed so can't be that.
If it's not a miss match of crank/cam sprockets or wrong camchain in a mk2 then it can only be the camchain sitting to the side of the the teeth on the crank or bunched in the main bearing cap.
Rotate the engine slowly whilst pulling on the chain to release the bunched links.
This seems more probable as even with the chain not sitting on the crank teeth there is usually plenty of slack to get the cams in easily and that problem is usually only discovered when rotating the engine to double check the timing.

I was thinking the same about slack....that sucker is so tight....really strange.... ya.....????

If everything else is correct for that engine then i'd bet my back teeth that the camshain is hooked up on the crank and there's a couple of bunched links possibly trapped against the main bearing cap.
Just needs half a turn of the crank whilst pulling up on the chain to release it.

That is a Mk II engine and those cam sprockets certainly look like they are 32t. If that's the case, you require a 124 link chain.

Alright Boys, thanks for the help, I have rotated the engine a little to line up TDC. But this does make sense. All cams and crank sprockets are original, just replaced the chain and the guide sprockets.

I will let you know.

Cheers and thanks,

Do you have the package the chain came in?