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.

...I Love my CHT gauge..I mounted it on the console..it's an Aircraft Spruce dual ga./cyl2&5...easy install..............Ron
http://forums.pelicanparts.com/uploads/FitipaldiB3.jpg
http://www.pelicanparts.com/support/smileys/munky2.gif

I've read enough. I'm modifying my center console. and putting in a CHT and a volt meter.
I watch my volt meter all the time in my 914. It shows when/if the belt is slipping.

I read Waynes post and he says to use 6 shims. I was told to use no shims so the belt wouldn't slip? Who is right? Also gonna throw my spare belt in the trunk tonight.;)

Using no shims could result in overstressed alternator bearings, a damaged alternator shaft and maybe eventually a "trashed" outer pulley and fan. Make sure you understand how the pulley adjustment works. All six shims must be installed either between the outer pulley half and the fan or on the outside of the outer pulley half underneath the dished or domed washer and the alternator shaft nut. Placing more shims between the fan and the outer pulley half (and fewer on the outside) reduces belt tension as the shims reduce the effective diameter of the pulley by opening it up and allowing the belt the ride further down the pulley groove. Fewer shims between the fan and outer pulley half tightens the belt. Just remember that all six shims must be somewhere; either between the fan and outer pulley half or on the outside of the outer pulley half. If you can't reach proper belt tension with a minimum of one or two shims between the fan and outer pulley half you have a stretched or the wrong size belt. Cheers, Jim :(

I'm towing the car tomorrow am. Oil change, leak down, compression test are all on the agenda.

Learnings so far:

1) keep 2 extra belts in the car
2) make sure I have the proper tools to do the job
3) practice changing the belt myself (at first under the watchful eye of a mechanic)
4) explore methods of getting an auditory signal vs. light only when the belt fails

I'll post as this progresses.
(I', starting to think that I'll never be able to just start, drive and enjoy this car without problems. Soooo many problems over sooo little time. :( :( :( )

Don't lose heart - you may be okay...

thrown_hammer - there are a lot of people who give advice on nothing that they know about. The fan belt is one of the more dangerous things to mess with. Check out the tech article:

http://www.pelicanparts.com/techarticles/911_fan_belt/911_fan_belt.htm

for the proper installation procedure.

If you don't have the extra shims on the outside of the shaft, then the nut may bottom-out on the threads. This will result in the nut being "loose." It will eventually fall off, or become loose enough to vibrate, cut-through, and destroy your fan belt.

This is serious stuff - not to be played around with. If you don't have the six shims in there, you shouldn't drive the car until you do. It can also seriously affect your alternator bearings as previously noted...

-Wayne

Wayne,
They are there, just between the nut and outer pulley half. So the pulley is at its tightest setting. I am going to read the tech article you referenced right now.
Thanks.

Lots of excellent cautionary info in this thread.
Seeing as you may have mere *seconds* to shut your motor down if the belt breaks, you really need a good warning indicator.

Personally, as effective as it may be, I don't want a big red "tail-light" stuck on my dashboard. And a CHT is great, but not down on the console; imo it would need to be up with the other gauges, right in the normal sight line.

So....I'm scratching out a simple circuit (relay(s), 12v Sonalert, etc.) that will howl when the alternator stops turning. With a bit of additional trickery, I think I can make it do so only *after* the motor is started, so it's not too annoying. (Slow day at the office.)

Wayne & Doug
 

"12v Sonalert"
Hey how about you two blokes get your scones together on this and rig up a "Pelican Parts" accessory?
This thread is giving me the willies!:eek:
Consider my order for one placed now.
:D

"12v Sonalert"

How about a voice synthesizer chip with a sexy female voice saying "Master alarm, fan failure; piston seizure in 20 seconds, master alarm, fan failure; piston seizure in 15 seconds, master alarm,......":D Jim

I don't want to destroy my 3.0 litre engine, anymore than anyone else but I think this fanbelt issue is freaking some people out. How often have you ever had a fanbelt break? I know they can break and it should be a place for concern. My way of sleeping good at night is to do two things: I carry a spare belt AND I change my fanbelt every year with a quality belt. Works for me.........................


<IMG SRC=http://www.pelicanparts.com/pmpre/images/N11Porsche/P-Car.jpg>


SmileWavy

Re: Wayne & Doug
 

I'll get in touch with the R&D division of the SCWDP.
We'll make them (exclusively) available to SCWDP members, at cost. Every 3.0 is worth saving from a meltdown.

I replace my fan belt every year... (just did it in April) I keep a spare as well as the old ones in the smugglers trunk along with extra relays, plugs, plug wires, CD box, fuses, roll of 16 ga. wire and asst. connectors, cap, rotor, air box strap, air compressor, two qts of oil, and a gallon of antifreez..... just kidding. :)

I also installed a CHT gauge along with a voltmeter under the ashtray in my car. I make it a habit to check all of my running gauges about every 3 minutes of highway driving.... it's natural to me now. Passengers even notice me brousing my needles and ask me what I'm doing.
I've been tempted to get one of those huge red "Stop The Car A-Hole!" gauges but I think they look horrible.
Doug you bring up an interesting idea.

I am getting to the point where I shudder at the thought of adding any additional electrical components to my car.... after the trouble i went through this weekend with my blinkers and windows... It just seems that every additional wire you add in there is another chance to cause problems.

In addition to the CHT and voltmeter gauge, I have also installed a stereo and hard wired a radar dectector.

Here's a shot of my gauge setup.
http://forums.pelicanparts.com/uploads/Leegauges3.jpg

Old or rountine belt replacement results in lot of belts being replaced and a portion of those installation jobs are botched. Hence belts still fail, often taking outer pulley/fan and sometimes alternator and engine with them. It's good to replace belts routinely but only if you do it properly. Cheers, Jim

Agreed! Belts don't fail very often at all, UNLESS THEY ARE INSTALLED IMPROPERLY.

The 101 Projects Book actually has a much better write-up on this topic than the tech article I wrote a few years before.

One tip from the book: tighten the belt, then turn the car over with the starter, and then retighten. Lather, rinse, repeat.

The nut will tighten down against the shims. This is very hard to explain, but I'll try. If you tighten down the nut and don't have enough shims on there, then you will pinch the belt. This will feel like: tighter, tighter, tigher, arrgh, I can't tighten any more. This is the way it would feel if you were tightening a retgular nut - it's basically linear.

The correct way is to have the proper shims in there. As you tighten the pulley, you will feel a certain amount of resistance that shouldn't increase too much. Then, all of a sudden, the nut will stop, and you won't be able to tighten it anymore. This will feel wrong, but is actually correct.

What is happening here is that you're compressing the belt slightly, and then the nut hits the shims and stops (while you're tightening it). This is correct.

If you do it incorrectly, you will have the pulley half compress the belt and squeeze it against the fan. This is INCORRECT, and will damage the belt if you run it this way (and possibly alternator bearings). The nut needs to bottom out against the shims.

The unused shims MUST be placed on the outside of the outer pulley half, between the spacer and the outer pulley half. Otherwise the nut may reach the end of the threads of the alternator and will feel like it's tightening down, when it's really not.

Hope this is clear...

-Wayne

The main thing is to ensure that you are using the proper amount of shims... either between the pulley half or on the outside between the pulley and nut, and that the pulley half isn't canted when you tighten it down... I usually tighten it while spinning the motor over by jerking on the pulley nut with a wrench.

The belt slips around the crank but it moves the fan and hence tightens on all sides of the pulley keeping it from being canted.
You will know if it is canted when you fire up the engine and you can see the pulley half wobbling...


Phoenix, I hope for the best with you and your engine.

This whole issue brings up a few points where experience with air-cooled VW engines is VERY useful, and every new 911 owner should change the fan belt ASAP ... just for the experience and practice, and recheck it over and over again just to be sure there aren't any problems with the installation! A bit of extra time to check fan belt tightness and condition can save a lot of grief and expense later!

1. It also lets you find out whether all of the proper tools are in the tool kit

2. it gives you the experience ... so a broken fan belt can be handled routinely, rather than as a catastrophe!

3. Fan belt(s) should be present in EVERY tool kit, both a brand new one, an an 'experienced' good spare.

4. Change your fan belt every two years, and you will probably never experience a failure!

5. Inspect your fan belt regularly ... if you need to add air to your tires, CHECK THE FAN BELT ... glazing is normal, but any cracks you find signals the need for a new belt!

This is serious stuff - not to be played around with. If you don't have the six shims in there, you shouldn't drive the car until you do. It can also seriously affect your alternator bearings as previously noted

No kidding. I just had to spend $50 ( 2.5 cases of Sam Adams) on a new outer pulley after reading posts that said install "5 shims". The lack of the 6th shim ended up destroying the outer pully half and probably contributed to the alt bearing going out. Luckily the alt was under warranty and Pelican was able to send me a new shinny new outer pulley half the next day.

Apparently some of the cars came OEM with five shims - this may be a function of the depth of the domed washer as they were different for various years and models; one has to look and see if the domed or dished washer (under the nut) is contacting the "squarish features" on the end of the alternator shaft; if it is and the belt is correct and correctly installed then one needs an additional shim. Cheers, Jim

For those planning on installing CHT and EGT gauges check outhere they make some really cool combo gauges like these they will even make 4 gauge combination gauge with warning lights etc. Appantely this company caters to the aviation field, you can have the gauges certified, but i think thats kinda spendywith a little ingenuity the triple square guage should mount where the clock used to live