timing belt tension theres always a loose spot???

[willnatale]

I bought a new timing belt and tensioner. I've done my timing like 5 times and when I got to crank it and look again the belt looks loose. Im not understanded what I need or have to do to keep it tight.

 

[steve]

Tell us in detail how you put the timing belt on and adjusted the tension.
That's going to be more valuable than another thread telling you how to and it will be specific to your problem.

 

[willnatale]

I timed the bottom end with the timing marks and the cams. I started at the bottom and worked my way up and I got all of the slack to the pulley closest to the firewall and then I tightened the tensioner arm where the other tensenior is and then turned it on but it seems theres a lose spot

 

[steve]

So how much force did you use on the tensioner pulley, what was you final clearance on the tensioner rod. How much clearance is there when the belt seems loose, and how much deflection of the belt. Thses are the details that impact the tightness or looseness of the belt.

The pulley closest to the firewall on a turbo DSM is the idler pulley not the tensioner pulley which is the one closer to the radiator. The tensioner pulley is where I recommend you finish when installing the belt. That means you start at the exhaust cam which is right above it. You can start anywhere but since the tensioner pulley is designed to take up the slack it seems best to end there.

 

[TSITurbo95]

^ Precisely. You want your slack to be in the front, so when you tension the tensioner pulley, it takes up that slack.

 

[willnatale]

Alright so redo my timing and get the slack to be at thw front where the tensioner pulley is and tighten it from there

 

[TSITurbo95]

^ Correct sir.

 

[jimbob_843]

Another helpful tip is after you tension it, rotate the crank 1/2 turn counter clockwise. This puts the slack on the tensioner, then re-tension the belt.

 

[steve]

Alright so redo my timing and get the slack to be at thw front where the tensioner pulley is and tighten it from there

If your timing marks all still line up there is no need to redo the belt.
If your auto-tensioner has the correct clearance (you can reinstall the retaining pin easily) then it's right and the belt is as it should be.

If all the timing marks don't line up correctly now, you had slack in the wrong places and will need to reinstall the belt.

If you still have balance shafts and didn't verify the correct phasing of the rear shaft/oil pump, you need to check it and reinstall the belt if the phasing is incorrect.

If you don't have the right clearances between the auto-tensioner body and the tensioner arm you will need to readjust the preloading of the timing belt.

 

[TSI_93]

You need to rotate the crank a 1/4th turn ccw before you do the 6 turns clockwise. It allows it pull out all the slack on the left side of engine.