Timing belt busted

Oh boy, that's gonna be a mess.

Bare minimum you're looking at probably 15-20 bent valves, damaged guides in the head, dented and possibly cracked pistons. Most likely extensive damage that will require a full rebuild if the engine is even rebuildable. This is why it's REALLY important to keep up with timing belt replacements. That inline 6 is a fantastic engine, real sad way to see one go.

You can probably find a Volvo guy to take it. If you offer it up for free, someone may well get it back on the road and fix it up.

There was a guy at the last Volvo meet I went to with a real nice 960 wagon he got for free with a broken timing belt.

I have a 1990 740 with the B234F engine that has 17677 mi. on a replacement belt.

Is there any statistical data as to how often breakage actually occurs?

I guess what I'm asking is - how often does it really happen?

Thanks,

Perk (:>)

The B200s are a little less stress on the cam and belt breakages are usually down to over-doing the mileage or service periods. It doesn't seem to be that common. They usually survive a broken belt I hear.

960s I know less about, but havn't heard of many belt failures atall atall.

-- Tony

I've seen a couple of 960s that died due to broken belts. Usually it's the same as the 16V 4's, people run them past the change interval.

It's possible for a belt to be damaged by oil leakage, improper installation, damaged sprockets, bad tensioner, or just a defective belt to begin with.

Honestly I don't know why Volvo chose to go with a belt for their interference engines, Saab used a chain, they're a lot less likely to break.

The B234F is the 16 valve 'interference' engine, vs. the B230F, 8 valve non interference. Both built on the same almost indestructible block (some minor differences on the 16). The only way I've ever blown up a volvo 8 valve was by loss of coolant. As James says, by the time you figure it out, it's over. Done story. There's no temp light, only a temp guage. Some have a low coolant sensor, but those tend to fail often.

I just blew up my 16 valve (91 940) by overheating it. I drove it

84,000 miles, ending at 284,000. I had the belts replaced as soon as I bought it, and then 2 februarys ago, I had it done again, because the idler for the belt driving the balance shaft had come unbolted. Somehow the two belts didn't contact each other and destroy the engine. Personally, after having several 8 valve engines, and one turbo, I dislike the 16 valve. You have to rev it to get it to go, and good luck working on the engine other than basic stuff. Expensive and special tools.

/glenn

They really ought to have an alarm. I blew hoses on my 740T twice and overheated it, neither time caused any damage to the engine, I guess I have a tendency to check the instruments often. I still always thought oil and temperature should have an obnoxious audible alarm that can't be ignored since they're such critical items.