Is my Cam belt fitted in the wrong direction?

[peteoddcar]

[youtube][img][size=200][/img][/size]]Hi all
Need some help here
Got the cam belt done last year - since then had a sort of whirring sound when engine up to temp. Was not there with the old one - following the threads a likely cause is a tight belt - I stripped it down to check tension if anything it’s loose a hood 10 12 mm free play at cam pulleys
Writing looks wrong to me see pictures
No arrows I can see on the belt?

[peteoddcar]

Had a good read up online - apparently they are not directional !
I’ll just set the tension and put back together.
I’ll post if the noise disappears

[Simon_P]

The original Isuzu belt was directional and quiet, but I haven't come across any aftermarket ones that indicate direction or are particularly quiet.

You may have missed that the tension is set at 60* ATDC (crank). You will get a different result at TDC.

10kg is about as hard as you can press with your thumb. It should be no significant difference in noise between cold and fans on. Too loose and the CAS will rattle.

[esprit888]

You may have read this, but note the comment about only adjusting the timing belt once!
https://www.gatestechzone.com/en/news/2 ... t-rotation

[peteoddcar]

Thanks all
I will check the tension at 60 ATDC, I am thinking that puts the cams in a no load ( or full load ? ) position but that’s a complete guess, perhaps the engine gurus can enlighten ?
- if still seems loose I’ll order a new belt as it seems I can’t adjust it - although I can’t understand why. By the time I get it back together it’ll probably be raining ... but if not whirring I’ll be ok

[muley]

You are correct, at 60 degrees after TDC the cams are unloaded and able to 'rock' slightly.

I have always assumed the belts are directional and installed with the writing facing outwards.

[peteoddcar]

I have always assumed the belts are directional and installed with the writing facing outwards.[/quote]
Me too - that’s why I posted my question.
Thanks for the input.

[esprit888]

I have always assumed the belts are directional and installed with the writing facing outwards.

Me too - that’s why I posted my question.
Thanks for the input.[/quote]

Me too, continental and Dayco actually tell you to have the writing facing you so you can read it in the clockwise direction of rotation

[FunElan]

Curious to hear if yours whirrs after the adjustment, mine has a very slight whir when fully warm. Planning on doing the whole timing belt this year sometime though.

[peteoddcar]

So update
I too was curious about a minor adjustment. I readjusted ( bearing in mind I’ll have to change the belt anyway) - I started the engine with it carefully supported on two jacks and tailored blocks
The belt and it’s associated pulleys make a horrid noise like something out of mesh every thing look perfect except the water pump pulley - it looks to me to have a slightly different profile to the other pulleys
I am going to order a new pump and belt and change it for peace of mind
Anyone know of rogue pumps - this one is a Delco. I am sure I read somewhere on here about water pump compatibility problems

[dapinky]

Pete,

Over the years I can only remember 2 highlighted issues with water pumps, the first was over 10 years ago when a small batch were made with square not round profiles on the teeth, but put into the same boxes as the good ones (I still have one in the loft as it's no use to anyone for anything). Maybe they would work fine, maybe they would wear the belt, I don't know, and didn't care as a new one was only £15 anyway.

Secondly, the 'newer' ones may or may not need a tiny bit of fettling to allow the case to clear the oil pump.... again, down to manufacturing, nothing else.

Have you ever changed the tensioner and idler (or have history to say it's been done)? that is the only other thing I can think of.

[peteoddcar]

Yes it was a kit that was supplied, but of unknown origin actually, and I assume installed all looks as new.
I had a new rock auto dayco kit but when we recommissioned the car for Andy we used my one and he got me another - I was pleased because it was Gates and Delco.
A mate did both cars with a few weeks gap - mine has made the noise since the belt was done - and as soon as it was done.
Planning longer trips this year and can’t do that with something not right
Another new kit I think

[esprit888]

Yes it was a kit that was supplied, but of unknown origin actually, and I assume installed all looks as new.
I had a new rock auto dayco kit but when we recommissioned the car for Andy we used my one and he got me another - I was pleased because it was Gates and Delco.
A mate did both cars with a few weeks gap - mine has made the noise since the belt was done - and as soon as it was done.
Planning longer trips this year and can’t do that with something not right
Another new kit I think

Sounds like the wrong profile on the pump but a good quality pic would confirm that if you can take one in there? I also recall other posts about owners receiving the wrong pump (profile).

[Rambo]

Yes it was a kit that was supplied, but of unknown origin actually, and I assume installed all looks as new.
I had a new rock auto dayco kit but when we recommissioned the car for Andy we used my one and he got me another - I was pleased because it was Gates and Delco.
A mate did both cars with a few weeks gap - mine has made the noise since the belt was done - and as soon as it was done.
Planning longer trips this year and can’t do that with something not right
Another new kit I think

In the scheme of things, and if you can do the work yourself, the kit ex Rockauto isn't that expensive. In fact, it's about 3 times cheaper than the equivalent from SJS or similar. My cambelts are on the other way round not that it makes any difference as the belts I've used don't appear to be uni-directional ie no arrows or writing on them. It just looks neater. although to be fair you can't see it when the cover is on

[peteoddcar]

Here’s a picture - what I have noticed from that there’s a fair amount of rubber dust around the pump so I think I am on the right track. Belt ready to remove now the crank pulley is off.
I’ll check the idler bearings when its all apart.
Seems the kits are out of stock at Rockauto
I’ll order SJ bits as I want them soonest

[Rambo]

Something looks slightly amiss there Half a tooth?

[peteoddcar]

I think it’s likely to be something like a missed final machining operation on the pulley ( or is it a gear ) , the teeth seem somehow too wide by a micron or two. I won’t take the belt off until I have the new parts in my hand but I am expecting to see abnormal wear on the pulley and the belt - both have only done less than a 1000 miles. The dust is the clue I feel

[Simon_P]

Is the tensioner fixed tightly?
What position is the tensioning hole relative to the bolt?

[peteoddcar]

Hi Simon
Thanks for your input
To answer
Yes tensioner was tight and the adjuster hex was at about 6 o’clock, when I re adjusted it seemed to work as it should.
Can the tensioner be fitted the wrong way up ? By which I mean 180 degrees out
I am putting new parts on next weekend so will report back.

[Simon_P]

The tensioner has an eccentric bolt hole so can be tensioned on the up side or the down side and. If loose, with the spring and rotation of the belt it would tighten or loosen accordingly - there is a correct way round, but I can't see that it would make a difference with the bolt tight.