Timing belt tensioner failure S70 T5 1998

The old Gray Goose just ain't what she used to be, I guess. My 740

8-valve does have a non-interference engine, and would be fine if the timing belt failed. My only guess is that performance has taken priority to these type things.

Buy a newer Honda, Toyota, Nissan, VW -- and pick up an old Volvo to tinker with on the side.

G'Luck!

snipped-for-privacy@pacco-> I changed the timing belt at 60,000 miles and was getting ready to

Who can do that with 4 valve technology, in the past with 2 valves it was possible.

Niels

Most other manufacturers who use a DOHC design use a timing chain, which is less likely to give way than a timing belt. Although operation is much noisier.

AC

Doesn't help anyway, the chain tensioner gives way instead and the pistons still hit the valves.

Exactly, it was the tensioner that gave way not the belt. But it´s right that a chain is muck more strong. You never see broken belts on the 23 mm wide cam belts on 850 / S-V70 models, it lasts 8 years or I believe 96000 miles. The problem in this case is most likely that the tensioner needs to be visually serviced from time to time and changed if looking bad. Furthermore you need to adjust / check the tension on it. Dont know if it was adjusted properly when he changed the belt at 60.000 miles.

Niels

Man, sorry to hear about the loss. This is coming from someone who also has a 1998 S70 T5 but was miraculously saved from the exact same disaster. One night, I was driving home, and the engine was making an odd sound. I had no clue it was the timing belt coming off its path. I was able to make it home w/o incident, and when I popped the hood, I could see that the belt had burned its way through 75% of the cover of the timing belt compartment.

After great advice from this group that night, I rented a car for the rest of the week and had the car towed to my mechanic the following weekend. The tensioner had fallen apart and lost all its bearings. At this point, I would recommend that all mechanics replace the tensioner when replacing the belt. The extra cost is worth it!

Mike

Many modern engines are interference designs. If it were me, my big complaints would be that the tensioner failed. I've also heard stories of failed water pumps blowing up these engines. Ouch.

John

Sadly, it is a common tale. I have known two people (one a family friend) whose Ford Escorts didn't survive until they were paid off because the water pumps seized. I forget which engine they used, but the damage was extensive. Our family friend had a neighbor (now her husband) take a look - there were chunks of valve seat embedded in the pistons.

Mike

It seems clear that driving the water pump from the timing belt is a very poor design. Much better to drive the water pump from the accessory belt like the alternator, p/s pump, etc. . That way a failed water pump is unlikely to grenade the engine.

I wonder what genius engineers made the decision to put the water pump on the timing belt ????

John

Funny to see all the people complaining only write one message and then no more from them. Why writing then?

Niels

You and me both! I guess the theory was that the water pump would always turn when the engine did, and another belt wasn't necessary. In any event, they didn't ask us what we think.... :-(

Mike