alternator belt failure - damage?
 

Hi all, my alternator belt hasn't actually snapped but is looking pretty rough so I'm going to replace it soon. I was just wondering if I were to use it now and it snapped would it cause instant damage to the engine? (as a cam belt snapping would cause on a piston engine for example)

Obviously it's connected to the water pump too...

It looks almost like it's been rubbing on something with one side blackened and one rib coming becoming detached in one place on the belt, can't see anything it could possibly be rubbing on!! Basically what I wanted to know is, is it going to be safe to still drive the car until I get it replaced!? Or am I going to have to leave it parked up for a while...

Thanks in advance, Jason

this actually happened to my miata. my alternator belt snapped. no visible engine damage but after about 5 minutes of driving on the highway my temp gauge went all the way up to 'H' and the 'Charge' light turned on. I pulled over and the battery was almost drained (had a hard time restarting the car) and my coolant was BOILING. i dunno if this applies to the 7, but i highly suggest not to drive the car for fear of snapping the belt and overheating.

Don't drive it in this condition unless absolutely necessary.

Think about it this way, would you like to replace a belt or an engine?:dunno: I'm sure you will make the right decision.

If you decide to drive it, don't ever ask for help on this site again.

wow ok Adam...! I was only asking! :) As I've seen in other posts that you can run without the P/S / accessories belt. But thanks for the help anyway!

I did mention in my post that I knew it was connected to the water pump, hence knew it would obviously overheat and need to be parked if it did break whilst out! I was more wondering if the revs would go crazy and cause the engine to blow (as a cam belt on piston engine!!)

It's parked up for now then anyway...

Thanks for all the replies everyone!

You are thinking of a timing belt on an interference piston engine where a piston can crash into an open valve if the belt breaks. There are no valves or pistons on an FD, as I am sure you know. :)

The alt belt also spins the water pump.

hehe what! they don't have pistons?! But they're got exhaust bearings and blinker fluid as I see on other posts! lol!!

Yeah, i was just wondering if they would be under a lot of tension when the engine's running, which may cause the revs to go through the roof if that load was lost due to the belt breaking!

No worries anyway, it's parked for now... trying to work out why it looks like it's been rubbing! there's nothing it could rub on and the pulleys look fine... I only noticed the difference today after a run out...

I know...:)

It won't over rev. I think the only thing you'll notice is the idiot lights coming on and your temp needle pegged. You also have less surface area on the pulley so it tends to slip. That's bad. But driving it like this will nearly guarantee a motor rebuild.

Sorry, I missed that.

Once I saw that you thought a snapped alt belt might cause damage to your engine internals, I kinda stopped reading ;)

this actually happened to my old car , it was a 1999 Mercury Cougar, ( surprisingly a reliable car!!! lol) and I was driving home and by the time I pulled into my driveway, I saw LOTS of smoke coming from under the hood. It was a small belt for the waterpump that had snapped. My temp gauge needle was actually reading PAST the "H" in hot!!!! It didnt do any damage, but ill tell you, If I EVER see 1 crack in any of my belts im replacing it!!

I suggest that you dont drive it...or else.

a friend of mines snapped one of his belt and it got caught in the back of the main front pully and damage the seal...after that the engine was never the same since he was loosing oil pressure and the car kept on shutting off on him all because he was too lazy to replace the belt...

Hi all, I fit the new belts a few days ago, nice and easy. It's squeeking away on cold starts now though! Like a bird chirping away under the bonnet... Stops squeeking when it's warmed up, but it's very irritating!

It doesn't sound like the belts are slipping at all... more like the pulleys are just squeeking away... spraying some WD40 on the pulley area (not the belts themselves obviously!) shuts it up for a bit... any ideas anyone? Belts not tight enough, too tight? I've got them to around 1/2 an inch slack when pressed! Though it is quite hard to measure...

the pullyes are squeaking?? maby you need to replace the pulleys. The pulleys should never squeak, and if they do, then its time to replace them, but do you know which pulley in particular is squeaking? I dont really measure my belt slack, I just mark it before I remove the belt