Timing Belt Change Dilemma
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Hello All, I have a 1988 944 Turbo nad I am trying to decide if it is worth the effort to change the belts. The belts have 9,000 miles on them but are five years old. During the last five years the car was kept in a heated garage. Today I took the top belt cover off and the belts look new, no cracking, fraying or other visible signs of wear. I also checked the tension and it was good to go. I just seems like a waste of time and $$ to change these belts. On another topic, it seems that the only way the tensioning tool fits on the cambelt is if one of the sides is wedged between the belt and the cover, is this the way it is supposed to be? Just doesn't seem right, although there is no other position which the tensioner will fit. Thanks in advance.
#2
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Sick... I think the general rule of thumb the more conservative folks around here go by is three years...
Rubber parts are affected almost as much by age as by miles.
For starters, try pushing in on the smooth side of the belt really hard; look at the base of the teeth on the inside, with really good light, really close, and see if any tiny cracks are visible.
One frequent failure mode is for these teeth to shear off, generally on the part of the belt rounding the crank pulley. Cracks at the base of the teeth are the first sign that you're heading this way.
If it was mine, I'd do the belts if in any doubt, esp. since you apparently have the magic tensioning tool. As a DIY, it's not that expensive. And the cost of _not_ doing it.... well, it's your money.
Jim... now if somebody will just invent & market an articulated metal toothed chain/belt....
Rubber parts are affected almost as much by age as by miles.
For starters, try pushing in on the smooth side of the belt really hard; look at the base of the teeth on the inside, with really good light, really close, and see if any tiny cracks are visible.
One frequent failure mode is for these teeth to shear off, generally on the part of the belt rounding the crank pulley. Cracks at the base of the teeth are the first sign that you're heading this way.
If it was mine, I'd do the belts if in any doubt, esp. since you apparently have the magic tensioning tool. As a DIY, it's not that expensive. And the cost of _not_ doing it.... well, it's your money.
Jim... now if somebody will just invent & market an articulated metal toothed chain/belt....
#3
Drifting
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That is the way I was tyaught to use the tool, plus I try to get the measuring cam as close to the center of the span of belt (between the two sprockets) as possible. When you check tension, slowly push the flat on the tool down until it clicks, being careful NOT to twist the tool - that would throw your reading off. When it clicks, I use a dental mirror to read the gauge without moving the tool. Then I slide it off the belts and repeat, etc.
I do a lot of autocrossing, and I change belts every 2 years (they are cheap) and the waterpump every other belt change. I look for leaking seals every belt change.
I retension at 1500-2000 miles.
I do a lot of autocrossing, and I change belts every 2 years (they are cheap) and the waterpump every other belt change. I look for leaking seals every belt change.
I retension at 1500-2000 miles.
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Belts will go a long time....I would run them much longer than that. If the belt only lasts 3 years, do you think they throw the new belts away after thay have been on a shelf somewhere? I doubt it too.
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John - "New" belts are discarded by the parts warehouser when they approach the expiration date.
Give that this particular car "sits" for quite a while without use, you're going to experience high-tension on some parts of the belt and low-tension on other parts of the belt. I would replace it every 3-4 years no matter how low the mileage on the belt is. Belts are like $40, and if you have the tool - labor is essentially "free".
Greg
Give that this particular car "sits" for quite a while without use, you're going to experience high-tension on some parts of the belt and low-tension on other parts of the belt. I would replace it every 3-4 years no matter how low the mileage on the belt is. Belts are like $40, and if you have the tool - labor is essentially "free".
Greg
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Thanks for all your input. I will order the belts on Monday from Zim's. I also have to find a wrench that will fit the tensioners for the balance shaft belt. I have the 9244 tool and it fits nothing, not the idler or the tensioner...what a waste of money. Did the newer tensioners get bigger? Or do I have an ancient set of rollers? Thanks again.