Drive Belt Tensioner Supposed To Be Loose?
#17
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Yep, a little right at the tip of the fastener and then that will distribute as you thread it in. Too much on a fastener that goes into a closed cavity and the hydraulic pressure from the loctite can actually crack the case metal. Happens on dirt bike engine cases all the time when people don't clean oil out of the holes before threading in the bolt and then they find a leak that wasn't there before.
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TheTorch (06-11-2020)
#18
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*1
Yep, a little right at the tip of the fastener and then that will distribute as you thread it in. Too much on a fastener that goes into a closed cavity and the hydraulic pressure from the loctite can actually crack the case metal. Happens on dirt bike engine cases all the time when people don't clean oil out of the holes before threading in the bolt and then they find a leak that wasn't there before.
Yep, a little right at the tip of the fastener and then that will distribute as you thread it in. Too much on a fastener that goes into a closed cavity and the hydraulic pressure from the loctite can actually crack the case metal. Happens on dirt bike engine cases all the time when people don't clean oil out of the holes before threading in the bolt and then they find a leak that wasn't there before.
#19
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No need to do that. If it was going to do any damage it would have already done it on the initial instsllation. Leave it be as it should be OK. Just a tip for future reference.
#20
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I over-tightened a pully/tensioner bolt on my 928 recently (doing the timing belt). The bolt head was large, but the shaft was narrow. I torqued per the large bolt head spec rather than the shaft torque spec, and snapped the bolt. Tightening as hard as you can can be a very bad thing too. There are published Porsche torque specs for the various size bolts. Even if you can't fit a torque wrench in the space, do a couple of "practice torques" with bolts on the work bench to get the feel for the amount of torque you want on the bolt, then torque by feel the bolt in situ. You'll be surprised how much less tightening is needed to meet specified torque specs in the normal case.
#21
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But beware of over tightening the bolt too. (you said "I grabbed an 8mm ratcheting wrench and tightened the bolt as tight as humanly possible").
I over-tightened a pully/tensioner bolt on my 928 recently (doing the timing belt). The bolt head was large, but the shaft was narrow. I torqued per the large bolt head spec rather than the shaft torque spec, and snapped the bolt. Tightening as hard as you can can be a very bad thing too. There are published Porsche torque specs for the various size bolts. Even if you can't fit a torque wrench in the space, do a couple of "practice torques" with bolts on the work bench to get the feel for the amount of torque you want on the bolt, then torque by feel the bolt in situ. You'll be surprised how much less tightening is needed to meet specified torque specs in the normal case.
I over-tightened a pully/tensioner bolt on my 928 recently (doing the timing belt). The bolt head was large, but the shaft was narrow. I torqued per the large bolt head spec rather than the shaft torque spec, and snapped the bolt. Tightening as hard as you can can be a very bad thing too. There are published Porsche torque specs for the various size bolts. Even if you can't fit a torque wrench in the space, do a couple of "practice torques" with bolts on the work bench to get the feel for the amount of torque you want on the bolt, then torque by feel the bolt in situ. You'll be surprised how much less tightening is needed to meet specified torque specs in the normal case.
#22
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Yep, it would be hard to get more than 44 ft.lbs. onto that via an 8mm wrench. I think you're good.
#23
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Put some red nail polish on it at 6 o’clock. Then you can check it. I had this prob last year , it has not moved since I torqued it the second time. Had to put a wrench on a wrench to get about a 8 inch lever to torque it a further 12.5 degrees or so