Have I done any damage?
 

My fan bell just broke and I still drove about 2 miles home. The temp never got above 220 (I coasted as much as possible) and I shut off all electronice but I did notice an inordinate amount of oil smoke after I shut her done and popped the hood. I seems as if she's leaking a bit more than usual. ( I have a spare and will put it on once she cools down a bot.)

Could I have caused some damage?

Very lilely, YES!!! Hard to say ... but, it shouldn't have been driven without TWO SPARE FAN BELTS in the tool kit!

<b>Do yourself a favor ... and don't EVER drive your 911 without a fan belt!</b> A four-mile walk to get a fan belt wouldn't have been that hard a task!

I guess you are one of several recent candiidates for Claude's Buggies (an air-cooled VW supplier) extra-large alternator/fan belt warning lamps ...

http://forums.pelicanparts.com/uploa...ingLamps-s.jpg

Shi__t, sh__t, sh__t!!! :eek: :eek: :eek:

What could have happend? Is there anything I can check? What shoudl I look out for. I'm about to go out and put on a new belt following.

Man I feel like an idiot!

put the new belt on then change the oil, if the oil was "overheated" it will lose it's viscosity then not lubricate/cool properly.
and yes......ALWAYS try to keep at least 2 extra belts in the tool kit.

The oil should be changed, of course, but that wasn't the real problem ... overheated cylinders, galled pistons, overheated cylinder heads, and warped sealing surfaces are the immediate areas of concern ... even if rod bearings weren't damaged in the ordeal! If, after an oil change, immediate valve adjustment -- not optional -- MANDATORY ... and startup from complete room temperature cool ... spitting/exhaust leak type sounds are heard, then just shut the engine off and have it towed to a shop, or pull the engine your self for a compression and leakdown test, and probable teardown!

Ultimately, pulled head studs from the Magnesium case are the real worry ... and that would neccesitate a complete rebuild!

The temp. never got above 220 max. (just over the 210 mark).

During drivers ed the temp reach that hot while driving it hard. This was a two mile trip with no rpm over 1500 and coasting most of the way at idle. Could I really have caused internal damage with this mild a drive? Especially on a newly rebuilt motor?

Now I'm really nervous! :( :( :(

Oliver,

I am not saying that all of the above damage occured ... just that those are some possibilities. I would be willing to bet that your engine at driver's school didn't smoke like it did today ... even though the oil temp was 220°F! The smoking is indicative that the cylinders and heads got very, very HOT, much higher than normal operating temps when the oil is 210°F!

Oil temperature is not really the issue, because it takes a while for 10 qts of oil to heat up, and finned cylinders and heads with no airflow can get very hot in just a few seconds, and cetainly in a few minutes!

Any estimate on the time it took yoyu to drive the two miles or so?

I have seen air-cooled motorcycle engines get galled pistons even before they got to the 'smoking' point ... so I know it is possible! Compression testing showed immediate damage on that particular engine, but honing the cylinder and replacing the rings returned that engine to service, to survive for many more years without any further incidents!

Jeez, with these damage possibilities someone could make a fortune selling a sticker to be mounted on the dash which says "NEVER DRIVE WITH-OUT A FAN BELT."

I feel for you Pheonix because I have to admit I wouldn't have thought 2 miles could have such ramifications either.

Hope everything checks out for you.

Well, look on the bright side. If you fried the engine, you can now do a 3.6L upgrade.

Hope everything is ok with it though....

I knew the "glass half empty" crew would have these dire predictions of the state of your engine.

You drove 2 miles and the temp didnt exceed 220.

I'm sure all the "experts" will chime in and tell my I am wrong with the advice I give you.

I would obviously install a new belt and start it up and see if the sounds are familiar....... an oil change would be mandatory, and while your at it a valve adjustment.

If the engine seems to sound and feel ( you can be the only judge of that) like it did before the belt breaking. Then drive the car (with your spare belt onboard) enjoy your car and learn the lesson about carrying spares.

If you drove 2 miles at redline without a fan belt you would have a major problem

2 Miles babying your car home wouldnt be something to lose sleep over.

TimT...I'm not sure if "the glass half empty crew" is an objective observation on your part...I thing an educated reply to the possible damage is worthy of respect.......Ron

Could I have caused some damage?

OK perhaps I prefaced my response incorrectly.

Yes you could have done damage, did you?

Most probably not

Ron on your big drive, if you were in the middle of nowhere and threw a belt would you have

A: had your car flat bedded to LI to check for damage?

or

B: changed the belt and continued your big ride with an ear more tuned to your engine?

My educated reply comes from years of building and maintaining many type of engines, air cooled, water cooled,oil cooled... 2 stroke 4 stoke, even a wankel.

I dont do this for a living i do it as a passion.

If I take my boat out of Jones Inlet run to the canyon for some overnight fishing, then I get an overheat warning while 80 mile from land , Ill stop the boat and usually remove a plastic bag from the intake on my outboard then return home when the day is done. Should I call Sea-Tow? No way. Ill continue the journey and monitor all the gauges and compare the performance to previous bookmarks.


2 mins at 1500 RPM, and oil temps not exceeding 200 arent something to worry about

2 mins at 7800RPM would be a problem

Tim..I'm not questioning your mechanical ability...And I think we feel the same way about getting the beast moving...8 and 12 foot seas/75 mi offshore or the 911 in the middle of nowhere..it's gonna run or it's gonna blow up.....peace brother...............Ron

I can't get that damned pulley off! The wrench that came with the car won't hold it (rounded tips and the pully's to close to the fan houseing to grab). I'm not playing with it anymore for fear of bending anything. I'm just extra p'd in that I'm just 2,000 miles or so back from a complete rebuild and litterally just had the A/C re-insalled. I would never have expected the belt to break now.

But, ok, I accept the car has to get towed. The question now is where.

I was planning to bring it to Rick Deman and have him Dyno it and adjust the carbs anyway. He's not my regular mechanic who rebuilt my motor in the first place (and to whom I've brought the car to several times since to get the carbs right.).

Rick is good but expensive. I just poured over $10k into this motor and now I'm facing doing this all over again. (I'm not sure how much more I can take and I know my bank account can't!)

So, do I go back to my regular mechanic or tow it to Ricks?

AARRRRGGGGG!!!!!!!!!! NOT a good weekend!

Early S Man: It couldn't have taken me more than 4-5 min. to get her home. No traffic and I made all the lights.

At this point just change the oil, put a belt on it, check the valves and compression. Sounds like you need a new tool to hold the fan also. If car runs good then go with it. I had the same thing happen with my 912 about 15 years ago, I didn't know the belt had broke, when arriving home the engine was quite hot, but it did survive.

I know how you feel, but all is not lost yet. You just have it try it and see what happens.

Dennis Varney

Struth:eek:
Dumb question - is the "alternator dash light" the only sign of warning that the belt has gone?
Is there any audible signal? It's just that it's not happened to me, yet. :confused:

Good luck Oliver, keep us posted.

Sean...I don't have an audible signal YET..been wanting to install a marine audible system, that is available at any marine supply store..no info on wiring, etc. I also want to install a gen lite where my windshield wiper delay sw. is located so it is closer to my line of sight.......Ron

Based on my own experience, I'd say that you have probably permanently damaged your engine.

Let's get some things straight here. Oil temps have nothing to do with cylinder head temps. The INSTANT you turn that fan off of the cylinders, the temperature is going to rise in the cylinders significantly. With that, metal will expand, clearances will decrease. It's very possible that the pistons may have scuffed the inside of the cylinders. There are a number of things that can and *will* happen.

JUST BECAUSE YOUR OIL TEMPS DON'T RISE, DOESN'T MEAN ANYTHING. THIS IS NOT A WATER-COOLED CAR, AND IF YOU THINK OF IT THAT WAY, YOU WILL CAUSE IT GREAT HARM.

If you had a cylinder temp gauge, I'm sure it would have gone off the charts. Obviously, oil temps take a much longer time to reflect the additional temps in the cylinder heads.

I can only think of one thing worse than running without the fan belt - running without any oil...

-Wayne

Oh, the same thing happened to me (in the engine now being rebuilt for the engine book). 2.7L fan belt slipped off because it wasn't properly attached with the MINIMUM SIX SHIMS!!!

I drove about 1/4 mile to the gas station, mostly coasting, and shut it off. 100 miles later 22 out of 24 studs pulled out of the case. And this was a case WITH time-certs installed. So you can say that the time-certs pulled out...

-Wayne

Towing
 

Oliver,

Your "regular mechanic" is the fellow who lacks experience with carb tuning, right? Is this the same person who evidently didn't change the belt when reinstalling the motor? Sounds like it's time for an upgrade.

Take it to Rick or Cheech, tell them what happened and have them do a valve adjustment, oil change and check the head studs at the same time. Also have them do a leakdown test which will help diagnose whether the valve seats warped, valves burned or stuck, piston rings seized/broke etc.

I would hold off on having them do any carb tuning, because if the leakdown shows, like 30% in one of the cylinders, your priorities will lie elsewhere.

Prepare yourself for the worst and then be pleasantly surprised if it works out better. Good luck and let me know if you need any help, I'm just over the river.