Timing belt a tooth out on cam sprockets?

[soldave]

 

I always lose complete confidence in myself when doing timing belt so could someone just sense check me please?

 

Got old belt off and new one starting to go back on although I'm getting a new auto tensioner rebuild kit (which may cure this worry I have). Got the belt around cam sprockets (aligned), ignition sprocket, and crank sprocket with crank at TDC but there seems to be a little too much belt slackness between cams for my liking. The problem is it's not a tooth worth of slack.

Once the tensioner is back on and engine turned by hand, will this tighten up and sort itself out or am I possibly a tooth off somewhere?

Done this so many times on cars but always makes me nervous so please be kind! 😁

https://youtu.be/xrAWgPsG2e4

[Escape]

It's hard to see in the picture but the clip does show quite a bit of slack. The exhaust cam could be one tooth out, assuming it can rotate half a tooth when the belt is tensioned. You could put a spanner to the exhaust cam to rotate it and tighten the belt, that will give you proof one way or the other.

[TAR]

Can't really see the timing marks in you picture. I would say that belt needs to move a tooth to tighten it.  

[soldave]

Certainly needs a tighten! The timing marks on the cams are shocking; once it's all timed I need to tip-ex a couple of new marks on there.

[TAR]

Are they not dimples stamped on the pulley?  

[Sparky]

One doesn't time and mark; one marks and times.

[Doris the dog]

This is the one for my 1976 Elite 

[Chillidoggy]

I can’t see any dimples on the sprockets in the photos.

[pbharcourt]

I think the problem here may be that you are lining up the words 'IN' and ''EX' in stead of the actual timing marks which are small dimples punched in the edge of the sprocket.

[Sparky]

I think it's clear to all that what we need here is a set of clearly marked timing dimples and a decent picture of them.  Anything else is pointless.

[soldave]

The marks are there in shot and the cams are aligned; it's just the dimples are super faint. Definitely nowhere else on the cam gears!

[Doris the dog]

Ok I need some advice from the good people on here regarding the cam belt for the Elite.  
The cam belt I was told that was correct was a Gates 5146, which I have fitted. The car runs , but it’s not road ready, so engine hasn’t been pushed. 
Soldave has started this post , and I now have doubts whether it’s the correct one , regarding belt width.  The 5146 fits but is 25.4mm wide, the cam wheel is 30mm. 
Is there a belt that is a perfect fit ?

What spec. are you fitting Soldave ?

[Chillidoggy]

Well, if they’re lined up why are we having this discussion?

[Sparky]

5146 is the correct belt.

Dimples, when closest to each other (unless head has been massively skimmed) will result in a fairly tight fit of belt teeth between the sprockets, without all the slack you've demonstrated.  It's that simple.

[Escape]

11 hours ago, Chillidoggy said:

Well, if they’re lined up why are we having this discussion?

Because they're lined up with a slack belt. Once it is tensioned, they will move out of alignment as the exhaust cam rotates to take the slack. I found it easiest to turn the exhaust cam back just a bit, enough to be able to easily fit the belt. When tightened the belt again both cams should align.

[Chillidoggy]

Surely, if they’re lined up with a slack belt, they’re not lined up? A decent photo would be nice.

[JerryS]

Hi Dave, just wondered - the marks may look aligned but are they level with the sprocket centers?

[Escape]

23 hours ago, Chillidoggy said:

Surely, if they’re lined up with a slack belt, they’re not lined up? A decent photo would be nice.

The little youtube clip gives a better view of things. But I agree, problem and solution have clearly been identified. In the end you can only be sure after everything has been properly tensioned and the engine turned at least 2 revolutions by hand.

[ramjet]

Unless I am mistaken, there are not dimples in the cam pulleys, but there are marks akin to divots on the inner edge of both pulleys. These appear to be aligned in the top photo. 1 divot beside the tooth underneath 'IN' on the LHS pulley and the other lined up with the 'X' on the RHS pulley.

I have coloured dimples in the outer edge of both of my pulleys as well and not marks like these.

I recall being concerned about my alignment and went through a bunch of checking once I had tensioned everything up. It all turned out ok.