AutoLinc

I'm confused re use of the 9201 on a 951 engine with the spring tensioner. The tension on the belt (right side after the cam pully) is higher than left side (before the pully) which is relatively loose, and this tension seems to change as the cam and engine are rotated through different stages. Should the tension, measured after the pully, be adjusted to be 2.7+-.3 when it is under maximum stress from rotating the camshaft, or should I try to get an even 2.7 on both the right and left (before and after) sides of the belt?

I'm practising on a spare, on the bench engine in preparation to doing a full front end job on a better, in the car engine. Is there possibly another issue I should look for (stuck roller or waterpump?) causing this uneven tension or is this normal?
Thanks,
AutoLinc
a hobby/dealer of collector sports cars

KuHL 951

Have you printed out the 9201 instructions in the factory service manual? If not I can email them to you. There's a very systematic way of doing the check.

Oddjob

When turning the engine over, the top side of the belt will be tight, and the bottom side will be slack - this is typical/common for any belt or chain driven machine. The tension is set by taking up the slack on the bottom side belt length.

Do you have the factory manuals, the procedure is outlined in there.

If not, there are two methods for tensioning and checking the belt:

1) using the manual tensioner and P9201 tool. Turn the motor over to TDC, then backoff counterclock-wise approx 10 deg, or about 1.5 teeth of the cam sprocket. This slacks off tension on the top side of the belt. The tool should be placed on the upper length of belt, between the cam sprocket and the crank sprocket. You will need to remove the metal belt guide (if your car has one) and probably the idler roller on the water pump.

2) using the auto tensioner. Roll the engine over to TDC, loosen the tensioner bolts, then tighten them back up. Simple. Not supposed to turn the engine back the 10 deg.

The manual never indicates or recommends using the P9201 tool to double check the tension set by the auto tensioner. But if you want to check the auto tensioner, you would need to tension using method 2), but after, roll it back 10 deg, then check for approx 2.7 units on the P9201.

AutoLinc

Thanks for the quick response, guys. No I don't have the shop manual yet, and a printout of the proceedure in the manual would be appreciated. For some reason I can't get the system here to accept my response containing an email addresss - try lincmgmt hotmail com.

George

83 944
88 944 TS