Heard squeal and POP!! but able to drive home

[RAM]

I was driving home yesterday from a great New Years Eve party and about 2 mile from my home I heard a squeal and a pop and the alternator light came on. The car still ran and I was able to make it home. Alternator died!!!

I removed the alternator, ordered a rebuilt unit (from Pelican) and overnighted so I won't be without for too long. My question is............

When I removed the alternator from the shround I noticed two cracks at the base of two seperate blades. Due to the fact that it took a while to remove I suspect that it has warped. Is this bad? Can I reuse the shroud? Shoud I either replace or weld up and dress the cracks. If I need to replace, how much are these things? Any thoughts?

[Rot 911]

I've been where you are now. Check out this thread of mine from a couple of months ago:
Fan Housing Cracked, Anyone Have a Used One?

[Botman]

RAM,
Are you sure it wasn't your fan belt breaking? Was the belt still there when you removed the fan/alternator assembly?

[RAM]

The belt was gone and there was a melted residue on both sides of the pulley when I removed the assembly. I rotated the alternator and I could feel grinding on the shaft The shaft wobbles as well when rotated. I assume this is a bad alternator.

[Rick Lee]

Dude, I think you're in big trouble. Sorry to sound so alarmist, but I think I've read here somewhere that you can cook your heads in a matter of minutes with a snapped fan belt.

[Decolliber]

You drove home with no fan belt?

[RAM]

I drove home in a matter of minutes. The oil temp. never reached above 180 F. I think I'm OK there (Thank God)

[old_skul]

Think again. I'd get a compression test done. I've heard several stories of heads that cooked with oil temps never reaching over 180.

This is one of those types of problems that the forum veterans will use lots of caps and exclamation points and italics with - if your fan belt breaks, turn off the engine - RIGHT NOW.

[RAM]

I don't have the tools for a compression test. What can I do a DIY Porsche mechanic?

I really didn't drive a lot and I was watching the temp guages carefully and not reving above 2000 RPM. I still might have a problem??

[pbs911]

Air cools the heads. The temp guage only tells you the oil temp, not the cylinder head temp. If you have a cylinder head temp guage and it never reached showed high temps you may be ok. You cannot tell the temp og the heads via the oil temp guage.

[Superman]

I'm one of those 'forum veterans' (so is Mark, BTW), but I'll stay away from the CAPS LOCK key. Indeed, you may have fried your top end. Compression tester or no compression tester, I'd probably just try to start the car. I hope you got away with this one, but it takes only a very short time for the damage to occur. Most of the veterans would not drive a 911 a block without a fan belt.

[Wayne 962]

CRAP - YOU'RE IN BIG TROUBLE!!!!

I'm not kidding here. The temperature that you measure on your gauge is oil temperature - not cylinder head temperature. If you drive with your car warm and no fan belt for more than 30 seconds or so, you will overheat your engine. Without a doubt, you overheated your engine, especially if it was fully warmed up. This happened on my car, when I saw the alternator light go on, I coasted into a gas station. The engine was so hot, I could hear the oil sizzling inside (not a good sign). 500 miles later 24 out of 24 head studs pulled out of the Timecerts that were installed in the case (completely ruined).

Even idling without the fan belt on will cause great, great damage. There is no method to cool the heads at this point, and the temps will just skyrocket. That will mean that your pistons may start scrapping your cylinders, and other good things...

Other than running your engine out of oil, this is the worst thing that can happen.

Nothing you can do now. Change the oil right away - there's probably a lot of dark, burnt oil in there. I would refill the engine, disconnect the engine, and let the engine turn over 30 seconds at a time with just the starter. This will build oil pressure and get oil into areas that might have been squeezed out (piston skirts) when the car was overheated. Don't run the starter continuously, or you might burn it out. Give it a minute or two rest, and then run it for 30 seconds. Do this about 5 times. It might not help too much, but it can't hurt, especially if your piston to cylinder clearances got really, really close...


On a side note, small cracks in the fan or housing usually aren't a major deal...

-Wayne

[RAM]

Now I'm really concerned. As soon as I get the alternator I will install and fire it up and see what happens. I should know better but at the time I was thinking about having to pay for a flat bed or push the car 1 mile, slightly up-hill home. Small price to pay for a potential issue but I'll just have to see when I start it up.

I'll have nightmares until I know for sure. At that point either my nightmares will get worse or I can sleep easy.

[RAM]

Wayne,

I will change the oil ASAP and do as instructed with respect to turning the motor over 5 time. I sure hope that all turns up well. If not, can anyone help with a rebuild in the Houston area?

[Superman]

You'll get the help you need here.

[RAM]

That's so true. When I was replacing the brakes this forum saved me roughly $400.00 in labor costs and tons of time.

Thanks for having all the help everyone!!!

[Drew_K]

I can't help personally with the rebuild, but I can recommend some local Houston Porsche mechanics if it comes to that.

[RAM]

That would be great!!! I'll keep everyone posted. I should have the new alternator tomorrow and I should have a better idea of what I ahve after the install. Until then, you know the drill!!!

[Zeke]

I'm not going to disagree just to disagree. I would simply like to give RAM some encouragement. I drove home once w/o a fan belt and I had one in the trunk. Call me foolish, stupid or what ever you want. About 2 miles, gentle uphills and down. Started the car, drove off, shifted into second, up to about 3000 RPM and shut it off and coasted until it stopped, about ten seconds. Waited two minutes and did it again. 4-5 cycles of this and I was home. Not any problems, hell I didn't even change the oil. Drove that car another 60,000 miles and the day I sold it, it was running strong, real strong, no oil leaks (Andial Motor).

RAM, ease up fella, unless your studs fall out like Wayne's, get in it and go.

BTW, Wayne, I was discussing engine break in procedure with an engine builder (about 500 Type I's to date) and we decided that it takes the motor the same amount of revoulutions for the oil pump to build pressure at any RPM. So you can use the starter to build up pressure, or you can just start it and have pressure almost instantly. Of more importance is the temp of the start-up oil and the load on the engine, IMHO. Once again, I'm not disagreeing just to disagree. But think about it. We might just put hot oil in my race engine and light it. Oh, yeh, my engine has assembly lube in it, RAM's doesn't. Still I wonder.................

[RAM]

Will do!!