We've put the timing belt on our ST170 this evening....everything seemed to go quite well, camshafts line up after turning g engine etc.....
however after turning engine over a few times the belt is 'walking' off the pulleys quite substantially
Has anyone else experienced this problem, could it be something to do with the tensioner....?
Thanks
Well can't be too many things... Are all the pulleys mounted tight, is the water pump worn. If you put a straight edge on any of the pulleys is it sitting level? I'm assuming the crank shaft pulley is fitted as that's what usually prevents the belt walking off.
there should be a plate on the outside one of the pulleys that stops the belt walking , if that is missing it will walk
Everything is straight and level, we have fitted a new crankshaft timing pulley.
On the ST170 Zetec the water pump isn't driven by the timing belt so that's not an issue.
There are no plates to go on the outside of the pulleys and to be honest on all the online photo's of these engines ive looked at i haven't
seen any plates on any of them. I know what you mean but not sure they are fitted/required on this engine???
Thanks for the replies
Ian
Sorry not too familiar with these engines but does it have a spring loaded tensioner?
*If* it does are you absolutely sure its set correctly to the instructions from the Kit/belt manufacturer?
The aux pulley would stop it walking off the bottom pulley.
In the cam belt cover backing plate there is a rectangle cut out to accept the tang on the tensioner. If this is not in its hole the tensioner won’t
sit square. Did you fit a new idler ? Ie a full kit ? This has a spacer on the back and buts up-to the same plate.
With the tensioner set you should be able to twist the belt 90deg with your finger and thumb on the longest length.
[Edited on 22/6/19 by big_wasa]
*If* you fitted a Gates kit make sure you follow their instructions to the letter
It's a Dayco kit with new spring loaded automatic tensioner.
We did put the aux pulley on the crank and it did lessen the amount the belt 'walked' off the other pulleys but not significantly.
Don't know if we were doing something wrong but when we lined the pointer on the tensioner up with the window in the back plate and then
tightened the tensioner bolt to torque it was a bit of a pig keeping the pointer lined up.
Think we'll have to take everything off and start again.
Double check the tensioner is fitted correctly
Hi what was the resolution to this? I'm having the same issue.
My belt consistently walks out, away from the engine until it rubs on the crank auxiliary belt pulley. This stops it coming off the cam sprockets but
the belt runs flush with the outer edge of the cam sprockets, tensioner and idler.
I'm concerned the belt will shred due to rubbing the crank pulley.
I have the fitted a Contitech kit with new tensioner and idler, the tensioner has an arrow that lines up with a box on the tensioner back plate, I
have tried setting the tension to each extreme of the box, and dead central, I then tried purposely being too loose with the arrow not in the box,
then slightly too tight with the arrow just past the box.
Each time it consistently walks outwards on the sprockets until it rubs the crank pulley.
Edit: Just to confirm, the belt walk definitely starts at the tensioner, it then works its way round the other sprockets and idler
[Edited on 15/6/20 by Slughead91]
my silvertop runs with the belt at the outer edge of the pulleys and tensioner. Always been like it and had no issues
quote:
Originally posted by big_wasa
....In the cam belt cover backing plate there is a rectangle cut out to accept the tang on the tensioner. If this is not in its hole the tensioner won’t sit square...
[Edited on 22/6/19 by big_wasa]
Yes the tensioner tab is slotted into the back plate
I've followed the Ford dealer service instructions:
Loosely fit tensioner
Fit belt
Then locate tensioner tab into back plate
Rotate tensioner so the hex key slot is at 4 o'clock position
Tighten bolt so tensioner can still just be tweaked
Then line up the arrow and fully torque to 25Nm
quote:
Originally posted by ttalps2000
my silvertop runs with the belt at the outer edge of the pulleys and tensioner. Always been like it and had no issues