Timing Belt Tension Poll....

[Tom]

Porsche's timing belt procedure is totally arbitrary. All we know is that if you rotate the motor forward 2 revs, then back 10 degree, then the fancy gauge should read ~2.7 when placed on just the right spot on the belt at room temperature. It's kind of like a bathroom scale that measures from F1 to W4, and saying your laundry should measure H3 if you wash it and then let it sit in the sun for 38 minutes, then add a cup of Elmer's Glue, then weigh it on the scale.

[blade7]

I voted for the twist/ water pump slippage since I’ve only changed my belts once and I’m as cheap as they come!

Not having to change the water pump every other belt change makes me tight too I guess. I wonder how many people have rechecked the tension of the timing belt when the engine is up to working temperature? I've just changed the belts and tensioners for the 3rd time in 15 years/23k miles. Each time the belts still looked to be in great condition.

Not sure why anyone would check it at operating temperature anyways. Tension measurements are intended to be done on a cold engine (0°C/68°F)

After 15 years and 23k miles, and who knows how long before that, my water pump bearing is still going strong. You do it your way, based on decades old thinking, and I'll do it mine.

[blade7]

Porsche's timing belt procedure is totally arbitrary. All we know is that if you rotate the motor forward 2 revs, then back 10 degree, then the fancy gauge should read ~2.7 when placed on just the right spot on the belt at room temperature. It's kind of like a bathroom scale that measures from F1 to W4, and saying your laundry should measure H3 if you wash it and then let it sit in the sun for 38 minutes, then add a cup of Elmer's Glue, then weigh it on the scale.

I think very early on there were some unexpected belt failures. Porsche went into engineering overload and haven't updated the procedure since. Despite belt tech improving, I used to work for Gates by the way.

[Darwin]

Not having to change the water pump every other belt change makes me tight too I guess. I wonder how many people have rechecked the tension of the timing belt when the engine is up to working temperature? I've just changed the belts and tensioners for the 3rd time in 15 years/23k miles. Each time the belts still looked to be in great condition.

Not sure why anyone would check it at operating temperature anyways. Tension measurements are intended to be done on a cold engine (0°C/68°F)

After 15 years and 23k miles, and who knows how long before that, my water pump bearing is still going strong. You do it your way, based on decades old thinking, and I'll do it mine.

Also not sure why people get so pissy.

[blade7]

Not sure why anyone would check it at operating temperature anyways. Tension measurements are intended to be done on a cold engine (0°C/68°F)

After 15 years and 23k miles, and who knows how long before that, my water pump bearing is still going strong. You do it your way, based on decades old thinking, and I'll do it mine.

Also not sure why people get so pissy.

Not me.