Timing belt loose

mattfromtn · Post by **mattfromtn** » 23 Sep 2016, 18:46

Rebuilding the head on my 98 s70 t5m and I have done several timing belts before but this one seems to be looser between the crank pulley and the intake pulley then it is everywhere else, any thoughts?

Replaced everything but water pump (hydraulic tensioner)

engine turns over 2 full rotations and stays in time

can back the crank off a bit to take up the slack but comes back when doing the 2 rotations to check timing

Thanks

Post by **erikv11** » 23 Sep 2016, 20:35

Maybe you didn't pull that section tight enough when you put it together? If there is an extra tooth in there, it will stay in there.

Post by **cn90** » 23 Sep 2016, 21:01

Did you release the pin on the hydraulic tensioner?

mattfromtn · Post by **mattfromtn** » 24 Sep 2016, 14:08

Yes I released the pin. I can back the crank off a bit to tighten it up and it seems even til I start rotating the engine forward again. Maybe the new tensioner isn't up to the task?

Post by **polskamafia mjl** » 24 Sep 2016, 18:29

Have you verified the new belt is the same length as the old one? Stupid question I know, but sometimes we overlook the easy stuff.

mattfromtn · Post by **mattfromtn** » 25 Sep 2016, 04:48

unfortunately i cut the old one off a couple weeks ago, its not loose enough to be the wrong belt for the mech tensioner, after a few rotations it seems to have tightened up abit hopefully it will be ok because i am going with it, thanks for the help guys

skloon · Post by **skloon** » 25 Sep 2016, 10:33

Did you tighten the heck out of the torx that holds the tensioning wheel ? so that it won't move

Post by **cn90** » 25 Sep 2016, 11:37

skloon wrote:Did you tighten the heck out of the torx that holds the tensioning wheel ? so that it won't move

Actually the tensioning arm is design in such a way that the tensioner pivots (or rotates) around the axis of the sleeve (where the bolts goes in). So with the bolt tightened, the arm is still free to rock back and forth.

Post by **rspi** » 25 Sep 2016, 12:12

When you turn the engine over clockwise, it takes the slack out of the front side first so I don't understand what you mean by turning it back removes the slack from the idler side???

One issue with having the head milled to much is that the timing belt will be loose.