Does a Timing Belt Wear Out From Old Age?

[doughnut]

My '94 J30 has 80k miles and still has the original timing belt which the manual says to change at 105k miles. A mechanic told me it should be replaced now because it's 22 years old and they wear out just like tires wear out even if they aren't used. Does this sound correct? I was hoping I could get another 5-10 years out of it.

[fourdrinie]

absolutely, the early models were rubber based belts.....time will allow the rubber to dry out, get brittle and deteriorate.....replace it asap

[doughnut]

Ok thanks for the info, I will for sure have that done. Should I be replacing the water pump or anything else at the same time even with only 80k miles? I only put about 2k miles per year on this car so I don't want to replace a bunch of things unless important.

[J30tChumpCar]

You could skip everything else if it passes inspection but remember a broken belt bends valves ($2000 to repair on top of the belt job)
Note: Water pump does note ride the timing belt, I have changed one without T-belt removal

[fourdrinie]

penny wise, pound foolish...
I would replace anything that moves under the timing belt cover....
there are rollers, springs, tensioners...all suspect to rust and corrosion...

something fails...your engine is toast....small investment

[dcarrd]

I guess it depends on how much you drive and how well you maintain your vehicle. If you've been driving with straight water in the radiator for some period of time(due to busted hose, leak, etc) then I would definitely replace the water pump. If on the other hand you service your vehicle properly and change your timing belt every 50-60k miles like some in the forum recommend then I think you can skip the water pump on every other belt change...but they're not that expensive and since you already went through the trouble of opening up the front then at least check it for leaks, weeping or rough spinning. If it doesn't feel right, change it.
The one Im restoring sat for 8 years with barely any usage. I replaced everything under the cover. Upon inspection found that the cam position sensor bearing was shot so I replaced the unit. The belt that was inside actually looked pretty good but I wasn't about to take a chance knowing all that time had passed without replacement. Now I plan to drive it for work, which is about 30k per year so I will be replacing it in 2 years but probably not the water pump if it passes my inspection.

[MikeRL411]

Good question! I replaced my 1997 J30T timing belt, the 108000 mile item, at 40,000 miles based on the calender! Now at 56,000 miles I have the recommended 216,000 mile replacement book requirement replacement timing belt replacement recommendation! Wondering if the recommended replacement mileage / age replacement guidelines are a "Cover your a**" manufacturer's recommendation or a wear and tear fact based requirement! Also, giving that the front end of the engine is thus exposed, should I opt to change the 20 year old water pump before it becomes an obsolete NLR item? If so, I would opt to receive the original water pump as a classic OEM item! It's your right by the manufacturer's warranty choice option! No charge, and it just might be the only world's choice when you really neeb to have a water pump rebuilt 20 years from now.

[vonscorpio]

I would replace anything that moves under the timing belt cover....
there are rollers, springs, tensioners

This. Just replaced the timing belt in my M30 due to age, not mileage. While it was apart replaced the tensioner, thermostat, water pump, etc. with new OEM parts. Didn't cost too much and gives me tremendous peace of mind.

[fourdrinie]

Nice to sleep at night!

[HarvesterUT]

Yes, old age can cause rubber parts to break down. I would replace the belt after 5 years or so. Might as well do a complete timing belt and water pump replacement job on the car. other parts can fail that will damage a new belt.