Turned the key on the 3 Liter...
#32
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+Plenty!! Well done and wishing you smooth sailing Tom.
#36
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Thread Starter
Thanks Scott for all your help with this motor. You saved this project for me right when it was going from bad to worse. The b/s belt is a new belt tensioned to new belt specs with the factory gauge. Seems like every time I put on a new belt, they whine like that until I re-tension. I presume Porsche's new belt spec errs on the safe side, for those rare belts that actually stretch. But, as the godfather of this motor, if you say to loosen it, I'll loosen it.
#37
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Tom,
It has been a pleasure working with you on your project. I'm glad to see you got it up and running.
Here's a little info, and my thoughts, on the belt whine...
Simply put, belt whine is an indication of over-tension, and without seeing/feeling it I am not sure exactly how much over-tension is applied. It is VERY likely that it is, perhaps, just slightly over-tensioned since you are using the factory tool.
Rarely do I get whine with my tension tool, and if I do, the tensioner hub likely moved a little during tightening. In which case, I go back, re-tension, and it goes away. As you mentioned, once you go back to re-tension, the belt will have grown a bit, and the noise will have subsided, but you do not want the noise after the re-tension. Heck, I don't like it before the re-tension.
Some think the noise comes from the belt being new and mating into the rollers, but that is not the case, it is simply over-tensioned (to whatever degree) - The logic behind the theory that the belt makes noise as it mates to the rollers, is that once the belt grows, the noise goes away. So while the theory seems logical, and has gained support, it is still wrong.
Running any belt in an over-tensioned state will do more harm than good for the belt itself. Think about it this way... If the belt is slightly over-tensioned to begin with, then the engine grows as it warms up, increasing the distance between the roller centers, then the belt gets even tighter. This causes two problems, first, the rollers are under additional lateral load, and second, the belt will stretch beyond its designed conditioned length. This can cause a premature failure of the internal fibers.
Try this on a cold engine, with the belt cover off, check the tension of the belt with you fingers (just wiggle it a bit) - Then warm the engine up to full operating temperature (coolant and oil temps in normal range) - Then check the tension again - That should give you a good idea of how much the engine grows.
Of course, if anyone else tries this and sees little difference in the belt tension, then your belt has structural damage and should be replaced.
Hope this helps!
By the way, I got your email. Let's follow up with a call sometime tomorrow.
It has been a pleasure working with you on your project. I'm glad to see you got it up and running.
Here's a little info, and my thoughts, on the belt whine...
Simply put, belt whine is an indication of over-tension, and without seeing/feeling it I am not sure exactly how much over-tension is applied. It is VERY likely that it is, perhaps, just slightly over-tensioned since you are using the factory tool.
Rarely do I get whine with my tension tool, and if I do, the tensioner hub likely moved a little during tightening. In which case, I go back, re-tension, and it goes away. As you mentioned, once you go back to re-tension, the belt will have grown a bit, and the noise will have subsided, but you do not want the noise after the re-tension. Heck, I don't like it before the re-tension.
Some think the noise comes from the belt being new and mating into the rollers, but that is not the case, it is simply over-tensioned (to whatever degree) - The logic behind the theory that the belt makes noise as it mates to the rollers, is that once the belt grows, the noise goes away. So while the theory seems logical, and has gained support, it is still wrong.
Running any belt in an over-tensioned state will do more harm than good for the belt itself. Think about it this way... If the belt is slightly over-tensioned to begin with, then the engine grows as it warms up, increasing the distance between the roller centers, then the belt gets even tighter. This causes two problems, first, the rollers are under additional lateral load, and second, the belt will stretch beyond its designed conditioned length. This can cause a premature failure of the internal fibers.
Try this on a cold engine, with the belt cover off, check the tension of the belt with you fingers (just wiggle it a bit) - Then warm the engine up to full operating temperature (coolant and oil temps in normal range) - Then check the tension again - That should give you a good idea of how much the engine grows.
Of course, if anyone else tries this and sees little difference in the belt tension, then your belt has structural damage and should be replaced.
Hope this helps!
By the way, I got your email. Let's follow up with a call sometime tomorrow.
#39
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Tough to fool trained ear, even on compressed video - LOL.
You probably had it spot on but the tensioner hub may have move a little (even just the amount of play in the wrench end could do it) - Back that baby off a bit and you should be good to go!
Talk to you soon!
You probably had it spot on but the tensioner hub may have move a little (even just the amount of play in the wrench end could do it) - Back that baby off a bit and you should be good to go!
Talk to you soon!
#41
Rennlist Member
I was thinking that even the tension gauge looked brand new out of a box.
er Tom, you do you iron your underwear don't you? Sick puppy.
er Tom, you do you iron your underwear don't you? Sick puppy.
#42
Three Wheelin'
#43
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Umm... I feel confident that I speak for the rest of us when I say I have no desire to know the details of your underwear. Thank you very much!
#44
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Don't worry Ehall, our frivolity is a mere speed hump to Tom. He doesn't even know we're here. hehe
Singled mindedness is not easily distracted by nincompoopery!
Singled mindedness is not easily distracted by nincompoopery!
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