Cam belt slipped off!!!! 1.8 TDCI

[baggy10]

Hi there folks,

Just wondering if anyone has had a this problem before? , Changed the cam belt on my fathers transit connect 1.8 TDCI the other day and had a bit of a nightmare!, marked camshaft sprocket with two marks on it and fuel pump sprocket and also marked old belt to sprockets then slacken tensioner and removed belt and also removed tensioner and fitted new one. Marked new belt same as old belt and refitted in anticlock direction starting at crank fitted belt and adjusted tension pointer to 3oclock and tighten to 50 nm like it said in the book! turned engine over by hand 2-3 times and checked my timing marks and they were spot on! also checked tensioner pointer and was still correct! job done i thought started engine and she fired up straight away and all sound good!. He took the van up the road to warm it up so i could change engine oil and filter! when he got back the engine was sat ticking over then!! started to rattle and stopped I thought hell what have i dont wrong, so popped bonnet and looked in and could see cambelt had rubbed through cover, took it all apart and inspected it and thought what is going on!!, so i fitted the old belt back on with my timing marks relined and retensioned and turned engine over about 12-18 times and noticed cambelt was being guided off at the tensioner. Removed tensioner and inspected and see the tensioner pulley is not machined square and on the piss .Just wanted to know if anyone has had this problem before or is it something i have done wrong! i have been a engineer for 18 years and done several cambelts and have had no problems. I also have got the auto data book on cambelts and know about the locking of the flywheel and the camshaft but i know for a fact nothing moved and my marks alined each rotation. If anyone has any sugestion i would be very grateful, or was i unlucky with a naff tensioner! it was a Dayco kit which are generally good? cheers Rich

[blue estate]

very strange i would take the kit back and get a conti or ford one as it sounds like the tensioner has failed

[MrMPuk]

Was the replacement tensioner the same type as the one you took off?

[BLUECONNECTION]

I ALWAYS use gates belt kits myself, did you loosen the cam pulley before you did the tensioner? it acts as a vernier pulley.

[baggy10]

Hi again folks,
The tensioner was a sprung loaded unit the same as the one that came off all looked the same! but to be honest didnt really look at pulley surface for squareness,! a garage nearby had a look and say the tensioner is at fault! but i just want to be sure! didnt loosen camshaft bolt and sprocket as blueconnection mentioned, was thinking about that but when i turned engine over and timing marks were all ok and tensioner pointer, would that be ok? The tensioner has a slight high spot in the middle and is tapered across away from engine it did about 2miles, just thinking back to basics belt was too tight would it not whine and maybe snap and if too lose maybe jump? i have been thinking of everthing possible, but maybe i have dropped a bollock by not loosening camshaft sprocket and bolt!!, but cant see that may cause problem when timing marks lined up each revolution of crankshaft. Like i said van started and ran fine untill 10 mins later you can see on the cambelt cover where the belt has rubbed through in the tensioner area!! thanks for your feedback cheers .

[MrMPuk]

You can't tension the belt without releasing the camshaft pulley.

[MrMPuk]

Did you sort this?

[baggy10]

Did you sort this?

Hi there, sorry i have just got back to it! been waiting for a dayco technician to visit garage and look at tensioner, they came down today!, and said it has worn like it due to incorrect installation!!!!, you said about if i slacked the camshaft bolt to release the sprocket and i can say i did not do that because i did not lock the camshaft! i would of thought after turning engine over a couple of times the belt would be at a correct tension between fuel pump and camshaft and tensioner would have settled? still cant see that it would knacker up the tensioner pulley to the way it was! I told the garage how i did it and they said i have dont nothing wrong, like i said before if a belt was too tight think it would snap and too loose jump a tooth but i guess i ballsed up but i still would like too know how it would cause pulley to go the way it did? gonna have to pay for this expense

[Wobby]

I have connects and do towards 1000 miles a week so have down a few belt changes over the years.

Correct way is to loosen camshaft sprocket, but i think thats more to get the cam timing correct rather than to tension the belt.

I have done them without loosening the cam sproket (at least twice) and not had any problem over the 60k i do in between changes.

You must have tensioned it to the correct tension with the markers and then you spun the engine by hand and checked the tension again? I usually start the engine and let it idle for a few mins then give it 3000 rpm a few times and then stop it and recheck it again for tension.

Sorry if i'm teaching you to suck eggs as it sounds like you know what your doing and you did it right in the first place. It does sound like a dodgy tensioner.

Rob

[baggy10]

Hi Rob,

Thanks for ur reply, thats interesting to know that u have done it the similar way before(not losening the camshaft sprocket) like u said the correct way is to loosen it etc, and like i said before i have dont other belts the same way with no problems! think this one has just bit me in the backside and because i didnt do it word 4 word by the book the manufacture can walk away from it, cant blame um!, still it just does my head in thinking i have made a mistake!!, been thinking of ever conclusion possible even about latchal forces? (push pull effect)? even the garage said i havent done anything wrong! still u live and learn

[tyson675]

I've just had the timing belt done twice on my 2002 Focus ST.Paid for it the first time,65mile later the timing belt snapped,pistons bent 8 valves.Cost nearly £1500!!!Glad I didn't pay for it!The garage showed me the failed pulley and it had sheared completely off...Don't know what make it was,weren't ford but also wasn't the cheapest!

[pagan86]

Done a customers focus tdci car today, done water pump as well, took about 3 hrs total, time you take under tray off etc etc etc!
Take bottom radiator hose off, drain coolant, header tank off, engine mount off (both parts),fan belt, change water pump, timing belt cover off, rocker cover off, alternator pulley off, remove blank in block, turn crankshaft until slot in cam is nearly level with head, screw locking pin into block, put plate in cam slot, belt and tensioner off, slacken camshaft bolt, knock pulley off so can turn freely, belt on, tension belt, tighten tensioner bolt and camshaft bolts to 50nm, stick back together,job done

[taz666]

Done a customers focus tdci car today, done water pump as well, took about 3 hrs total, time you take under tray off etc etc etc!
Take bottom radiator hose off, drain coolant, header tank off, engine mount off (both parts),fan belt, change water pump, timing belt cover off, rocker cover off, alternator pulley off, remove blank in block, turn crankshaft until slot in cam is nearly level with head, screw locking pin into block, put plate in cam slot, belt and tensioner off, slacken camshaft bolt, knock pulley off so can turn freely, belt on, tension belt, tighten tensioner bolt and camshaft bolts to 50nm, stick back together,job done

bloody hell that's the long way of doing them

[pagan86]

got to do what boss tells you mate, told to do it by the book!
If it was my own car the paint marker would be out,lol

[taz666]

I line up the camshaft with the head and then only put one mark on the the pump gear as it it matched to the crank every thing else is done properly, just saves having to take the alternator or the drive shaft to the alternator off to fit the pin