My First Cambelt Change, Why So Difficult?

[GLPoomobile 958]

What's the crack with new cam belts? Should they slip right on provided the tensioner is retracted?

 

I've sepnt 2.5 hours pissing about today trying to get the new belt on and had to give up as there was not enough free play to get it over all the wheels. I ended up putting the old one back on and even that was an absolute sod! Not helped by the fact that my hands are sore and I have less muscle mass than Nikki from Big Brother

 

I just don't get it! The new belt is the correct part, a 113 tooth belt the same as the old one. I have a spring loaded tensioner and that was retracted to it's maximum. Both pulleys were in the correct timing position (not that it makes an odds to the problem). The belt was fed on in the correct way, but the it was just like maybe 2mm too short to hook over the crank pulley.

 

With the old belt I tried hooking onto the crank pulley as the final step with no success and then went back to doing as Haynes says and to start with the crank pulley and then hook over the cam pulley with the tensioner and water pump last. Well there was no way that would have worked so I did the tensioner and pump and onto the cam pulley last of all. Was the mother of struggles but just got it on. So is this normal?

 

Also, having released the tensioner and turned the crank a few times and then re-tensioned, the belt still seems a bit loose on the longest run, can twist it about 90 degrees.

 

Lastly, although both timing marks matched up with the marks on the pulleys when I put the belt on, they obviosuly don;t match up after a few turns. I seem to recall reading that the enginee needs to go through about 22 revolutions before the marks match up again, is this right? Should I just trust tha it is OK as I can;t see that the belt would have slipped at all as it feels tight on the pulleys (despite not feeling properly tight on the longest run).

 

Sorry for not searchin but I'm in the internet cafe and in a hurry. Will check back for replies later. I'm desperate as I have to get the car sorted for the MOT on monday so I can get taxed, and at the rate I work and sods law for things going wrong I can see time slipping through my fingers

 

Edit: One other thing - I tensioned the head bolts to 75 lbs ft as per Dave Bakers guide. Is it possible the head is not bolted down enough and the extra distnace between head and block could account for the problem above? The bolts for the top engine mount that go through both head and block are in place and done up so I would expect it to be OK. Just a thought.

Edited July 27, 2006 by GLPoomobile

[TEKNOPUG 3]

Not sure if this is applicable on 205's but......my grandad used to cut the current cam belt longways down the middle. So effectively you would have half the width of the belt on the pulleys. Then push the new belt on halfway, cut the old belt and slide the new belt home. Thus doing away with having to release the tensioners and worry abou the timing marks etc.

[boombang 2]

thats a very good plan actually! Not sure if we got the space down the side of a Pug engine bay but worth a shot

[Jonmurgie 2]

The first time I did this (and the only time with the engine in the car) it was a complete b!tch of a job and it took me nigh on the whole weekend! It does go on but as you have found out it's proper hard, you just have to tease it over the very edge of all the pulleys really, get it too far on one pulley and it won't go on another one.

 

No other advice other than keep trying sadly...

[vince 0]

hey!!

 

I'm rather surprised it gets so difficult... 2 or 3 months ago I replaced the water pump on my 1.6, and I was actually surprised to see how easy it was compared to the turbo Ds and Ds .

then, I can't actually tell you what is wrong, as it went smoothly for me, just keep on trying....

you may try to get a better access by moving the engine away from the right hand wall as much as you can. it won't actually install the belt, but it may ease your life.

 

regarding the head bolts torque, don't believed it should change anything. the difference of torque can't give you a 2mm difference,which could only come from the cylinder head gasket and would mean more ore less crushing. the gasket itself is 3mm (more or less)...

 

if the mark are not aligned after few turns, then something is wrong.

 

hope it helped

 

good luck

 

vince

[jim21070 2]

With the tensioner released fully, the belt should slip on with no problems. I'd recheck that the tensioner is coming off properly as it is so easy to turn the square drive and for the cam to ride up over the lip at the back of the tensioner and thus prevent the tensioner retracting fully. Often this lip bends a little in trying to get it to release and this in turn causes less than full travel. The tensioner jockey wheel should move a good 6-8mm from tensioned to fully off.

 

This is often caused because the two 10mm tensioner fastening nuts are too tight to allow the tensioner to fully and easily retract, hence causing the lip to bend. Loosen these off a good few turns to allow the tensioner assembly to tilt a little and you'll have a little more to play with. The tenioner jockey wheel is now effectively at an angle, making the belt easier to slip on.

 

I've never heard of needing to rotate the engine 22 times before the timing marks line up again. They should always line up otherwise your timing will be off. Sometimes, with a loose untensioned belt it looks right but when the tension goes on it appears to slip a tooth. The way to prevent tis is to ensure the long belt run between the crank sprocket and cam sprocket is tight before you let the tensioner out. Belt slack will then be taken up between the crank, waterpump and tensioner and will not "pull" the timing off.

 

Check your timing again with tension on after two full revoloutions of the engine, then another two and a further two for luck. Go through retensioning the belt again, now it is settled, and recheck the timing another couple of times.

 

Don't forget to make sure the two 10mm tensioner nuts are tight!

 

Good luck and good luck with the MOT!

[ALEX 98 1 Cars]

With the tensioner released fully, the belt should slip on with no problems. I'd recheck that the tensioner is coming off properly as it is so easy to turn the square drive and for the cam to ride up over the lip at the back of the tensioner and thus prevent the tensioner retracting fully. Often this lip bends a little in trying to get it to release and this in turn causes less than full travel. The tensioner jockey wheel should move a good 6-8mm from tensioned to fully off.

 

This is often caused because the two 10mm tensioner fastening nuts are too tight to allow the tensioner to fully and easily retract, hence causing the lip to bend. Loosen these off a good few turns to allow the tensioner assembly to tilt a little and you'll have a little more to play with. The tenioner jockey wheel is now effectively at an angle, making the belt easier to slip on.

 

I've never heard of needing to rotate the engine 22 times before the timing marks line up again. They should always line up otherwise your timing will be off. Sometimes, with a loose untensioned belt it looks right but when the tension goes on it appears to slip a tooth. The way to prevent tis is to ensure the long belt run between the crank sprocket and cam sprocket is tight before you let the tensioner out. Belt slack will then be taken up between the crank, waterpump and tensioner and will not "pull" the timing off.

 

Check your timing again with tension on after two full revoloutions of the engine, then another two and a further two for luck. Go through retensioning the belt again, now it is settled, and recheck the timing another couple of times.

 

Don't forget to make sure the two 10mm tensioner nuts are tight!

 

Good luck and good luck with the MOT!

 

Yep shouldn't have any problems like that when fitting the belt.

Sounds like the tensioner isn't locked back fully as said above.

If you undo the 16mm lock nut too much the cam lobe that retracts the tensioner slips over the lip on the tensioner.

I fit the front of the belt first using the marks on the belt with the marks on the pulleys. then I use the slight play in the locating dowels to get the belt tight between the two pulleys. The rest of the belt should hook round the water pump and tensioner pulley with ease.

To tension the belt release the tensioner cam (but don't lock it down) remove the dowels then crank the engine round by the crank pulley (not the Cam pulley). Do a couple of full revs then watch the tensioner as you crank it over. It moves in and out slightly. When its at the furthest right lock it down to give the tightest possible belt tension from the tensioner.

 

Alex

Edited July 27, 2006 by ALEX

[pug_ham 244 3 Cars]

I stalled doing a cambelt on my car for ages, when I bought it I paid Pug to do it but when it came round for doing again I was determined to DIY & it was so much easier than I expected I'd gladly offer to do them anyday.

 

I didn't even talke the engine mount off to do mine & it was still done in under three hours.

 

It sounds as if your tensioner has slipped back slightly & is putting tension on the belt, with it completely pegged back the new belt should slide on easily, hook it on the front side first though so its longest run between pulleys is a smooth sliding fit & then work it round the water pump & tensioner but this is almost an in one move job anyway.

 

Just like Alex says.

 

Graham.

[GLPoomobile 958]

I'm certain that the problem is not the tensioner. I made sure the two 11mm bolts were loose enough and that the 16mm nut was loose enough to move the tensioner cam but not loose enough for it go wrong (if you know what I mean). I retracted the tensioner to it's fullest and locked it back in place, then looking down the side of the engine at the tensioner spring I could see that it was fully compressed, all coils squashed right up. I don;t think I would be able to get it any more compressed tha this and hence I don't think it is the tensioner that is causing the problem.

 

So, the only other thing I can try is to follow the advice above and to try and get full tension in the longest run by turning the crank pulley to take up the free play. This might give me enough extra slack to slip the belt over the last wheel, but thinking this through in my head, I think that by doing ths I might end up with the cam and crank pulley timing marks out of sync.

 

By the way, when I was referring to the timing marks not matching up I was talking about the marks on the belt, not the pulleys. The crank and cam timing holes still match up after turning the engine by hand, it's the marks on the belt that do not match. But having searched it appears that this is not so important as long as the holes match up and that it takes 60 revolutions before the timing marks on the belt match up again.

 

I think I'm going to keep the old belt on for now and take it easy on the way to and from MOT and then try to fit the new belt afterwards, don't really have time to fanny around with it again. It is in OK nick, the timing should be right, I juts need to get it properly tensioned which I think I can do now having read the advice.

 

Final comment - getting the belt on with the engine mount in place is a bit of a fiddle but totally doable and far easier than the hassle of getting the mount off. Just thought I'd mention that to anyone reading this who thinks that you need to remove the mount.

 

Thanks for the replies.

[sorr 0]

I personally would not put the old belt on and start the car never mind driving it. The old belt may look OK, but visual inspection will not tell you the belts true condition.

 

Are you sure that you have the correct new belt, as if you the old belt goes on easily so should the new one. If the belts are the same length I would have another go as I have never had problems sliding a belt on.

[Wurzel 16]

To tension the belt release the tensioner cam (but don't lock it down) remove the dowels then crank the engine round by the crank pulley (not the Cam pulley). Do a couple of full revs then watch the tensioner as you crank it over. It moves in and out slightly. When its at the furthest right lock it down to give the tightest possible belt tension from the tensioner.

 

Alex

 

 

That might work but I've got to say I forgot to clamp the bolts down on my engine and when I attempted to manually turn the engine, the belt slipped

 

I guess it could have been a weak spring though.

 

I'm pretty sure the answer to your problems is what Jonmurgie has mentioned. You need to slip the belt on a little bit at a time on both pulleys. If you place it on fully on the top pully, it won't fit over the crank pulley.

[ALEX 98 1 Cars]

That might work but I've got to say I forgot to clamp the bolts down on my engine and when I attempted to manually turn the engine, the belt slipped

 

I guess it could have been a weak spring though.

 

If you turn the crank clockwise (engine direction) the tension is kept between the both pulleys so it shouldn't slip.