Alternator belt popped

[sabeo.m]

Hi everyone, so as the title states, after a spirited drive this afternoon my alternator belt popped off the pulley. Luckily i notice the red alternator light come on, so i pulled over and was able to get the belt on again with a flathead screw driver. Half way home the belt came off again, this time i was bumper to bumper traffic. only about 15 minutes from i decided to chance it, while keeping an eye on the oil temp. when i arrived home the oil temp was roughly 220F, the engine was HOT! I immediately shut the engine off. So i figure next on the list: oil change & filter, new alternator belt (x) 2, new pulley shims. Is there anything else i should check? I know the engine got very hot, i hope it didn't sustain any damage.

cheers,
saab.

[RSTarga]

Cylinder head temp is not the same as oil temp. Tow trucks are cheaper than engine rebuilds. I'd do a leakdown test along with all of the above.

[sabeo.m]

Cylinder head temp is not the same as oil temp. Tow trucks are cheaper than engine rebuilds. I'd do a leakdown test along with all
of the above.

Your right, thats what im afraid of. Will get leak down as well, thanks!

[Cooper911SC]

You shouldn't need "new" pulley shims.

There should always be 6 total. I would get a new Genuine Porsche belt. Not the 'OEM' Continental belt.

There have been several posts here, and I know of a few people and local P shops who have seen the Continental belts being too long from new, and therefore not adjustable for proper tension, from new.

I would install the new belt with maybe 4 shims in and 2 out. Or 3 in 3 out.

Mid belt you should see ~ 1/4" deflection when pressed by finger.

When installing the new belt I get the shims in and cup washer, then finger tighten the nut plus 2-3 turns of the socket. The belt will begin to ride up in the "V" but also get pinched. Stop and go "bump crank" the engine 1-2 times with the key. This will rotate the pulley a couple of revolutions and un bind the belt. Now tighten the nut.

Start the car and re check belt tension. Adjust if necessary, or go for a short drive.

Re check the belt.

Cooper

[sabeo.m]

Originally Posted by Cooper911SC

You shouldn't need "new" pulley shims.

There should always be 6 total. I would get a new Genuine Porsche belt. Not the 'OEM' Continental belt.

There have been several posts here, and I know of a few people and local P shops who have seen the Continental belts being too long from new, and therefore not adjustable for proper tension, from new.

I would install the new belt with maybe 4 shims in and 2 out. Or 3 in 3 out.

Mid belt you should see ~ 1/4" deflection when pressed by finger.

When installing the new belt I get the shims in and cup washer, then finger tighten the nut plus 2-3 turns of the socket. The belt will begin to ride up in the "V" but also get pinched. Stop and go "bump crank" the engine 1-2 times with the key. This will rotate the pulley a couple of revolutions and un bind the belt. Now tighten the nut.

Start the car and re check belt tension. Adjust if necessary, or go for a short drive.

Re check the belt.

Cooper

Thanks for the suggestions Cooper, much appreciated.

[gsxrken]

Make sure during that starter bump process that the shims stay centered. If they slip down and you tighten them, they get all bent up and your pulley may not run true.
Make sure your issue was simply a stretched belt and not a pulley and fan combination that got oblonged due to wear from being loose. That will require a new fan and pulley half to fix.

[quattrorunner]

15 mins with no airflow to the cylinders and head? Hope you have super oil for protection. That's too much.

[sabeo.m]

Hey guy's, got the new parts, installed new pulley,shims and belt. I realized that when I had to do a emergency belt swap at the track I foolishly put four shims back not six. All is good now, thanks for the help!