Timing Belt--What to replace after 7 years and 35K

Post by **atucker1** » 25 Jul 2021, 04:24

So I have a 1995 850 Turbo with 205,000 miles. The timing belt was last done at 170,000 miles in summer 2014 and everything was replaced with OEM parts--belt, tensioners, idlers, and water pump. Now, it's been 7 years, but only 35K miles, so I'm wondering which parts I should replace. Obviously I'm putting on a new belt, but do I need to replace the tensioners, pulleys, and water pump too? I was thinking that the belt itself would deteriorate a lot with age, but the water pump and tensioners and idlers would be worn mostly by mileage.

My default here would be to just replace everything, but I know there's a lot of discussion about the longevity of these parts so I'm wondering if it would be pretty safe to just change the belt. Thanks in advance for your advice!

Post by **jreed** » 25 Jul 2021, 06:15

Everybody's going to have their own situation, outlook and abilities, so there will be differing opinions on what to do. If I were in that situation, and assuming the engine coolant had been well maintained, I would most likely replace the belt, tensioner, tensioner pulley and idler pulley. I know some re-use the tensioner, but in my opinion it's less work and less worry (though much more expensive to be sure) to install a new one. The old pulleys might be fine for another 7 years, but they might not, so I'd replace them too.

Post by **misha** » 25 Jul 2021, 07:18

I would leave the timing belt untill 2024,since it's been replaced in 2014.
Idlers and tensioner too if tensioner is hydraulic.

Oem water pump is good for 200+k.

So....i wouldn't replace any of those....yet.

Post by **jreed** » 25 Jul 2021, 08:00

I was thinking that the recommended change interval (at least in the US/UK Haynes manuals) for the timing belt was 7 years or 70k miles, whichever comes first.

Post by **Sveedy** » 25 Jul 2021, 09:10

Trying to wrap my head around a shelf life for a timing belt. Obviously if it was just sitting in its box, then it would be fine after 7 years.
If it was installed and used for 2 years, then removed for 5, would it still have to be tossed ? Or is it a perceived issue with it sitting on the gears under some tension, even though it's not rotating ?

Post by **jreed** » 25 Jul 2021, 11:35

I don't know the answer about storage lifetime, but in general I would most likely choose to purchase a new belt rather than re-use an old one because they're relatively inexpensive compared to the pulleys and tensioners.

Post by **misha** » 25 Jul 2021, 13:28

Volvo and Conti timing belts have date of manufacture stamped on them.
They are sealed in the transparent bag and have something like powder on them.

Post by **misha** » 25 Jul 2021, 13:32

Sveedy wrote: ↑25 Jul 2021, 09:10 Trying to wrap my head around a shelf life for a timing belt. Obviously if it was just sitting in its box, then it would be fine after 7 years.
If it was installed and used for 2 years, then removed for 5, would it still have to be tossed ? Or is it a perceived issue with it sitting on the gears under some tension, even though it's not rotating ?

I think that i read on Conti package that it should be installed within 3 years from manufacture date stamped on it.

On the other hand....i would toss the belt which was removed from the car and kept in storage for 5 years.
If it was brand new and unopened for 5 years...i would use it.

Timing belts lasts way more than recommended replacement interval....at least double...if you don't push the engine hard by smoking the tires and something like that(which can be seen on youtube videos).

Oil contaminants and seized idler, tensioner or water pump is what makes them to fail prematurely.

So....if replacement interval is 7years or 70k miles...and you reached the time but not mileage....i would leave it up to 70k but not more than 10-11years.
Mainly because the replacement interval on p2 cars was moved to 10 years or so.
Width of the belt should be the same for p80 and p2.

Recommended lower replacement interval of 50-60k was with narrower timing belt on early 850 from '92-'94.

Post by **Clemens** » 25 Jul 2021, 13:52

misha wrote: ↑25 Jul 2021, 13:28 They are sealed in the transparent bag and have something like powder on them.

Oh, that's how you smuggle Columbian bam bam commercially...

Post by **misha** » 25 Jul 2021, 14:39

Clemens wrote: ↑25 Jul 2021, 13:52
misha wrote: ↑25 Jul 2021, 13:28 They are sealed in the transparent bag and have something like powder on them.
Oh, that's how you smuggle Columbian bam bam commercially...