help me identify that noise / issue
 

After some spirited driving last night, I started to feel some vibrations that got worse with time; within 10 min the grinding / tapping noises were getting louder.
This a.m. I started the car and made that short video.
It sounds like it's a belt issue -there is quite a bit of "rust dust" around the AC compressor's pulley and on both belts.

I'd really appreciate it if someone could give me some input about what the problem sound like, and what the remedy would be. Thanks in advance ! SmileWavy

<a href="http://s177.photobucket.com/albums/w233/frenchsailor/911/?action=view&current=CIMG3805.mp4" target="_blank"><img src="http://i177.photobucket.com/albums/w233/frenchsailor/911/th_CIMG3805.jpg" border="0" alt="Photobucket" style="width: 160px;"></a>

- Olivier

Fan belt is jumping....could be the pulley.

Thanks Joe; I do see the fan belt jumping / getting loose, as if the fan pulley was indeed seized somewhat. What would be the part number if I'd want to replace (both?) pulley(s) ?
I can only find the outer one:
Pelican Parts - Product Information: PEL-RS-PUL2-BLK
Thanks !

I had a similar sound, my belt was too tight, not too loose.

I had tightened up the belt so I could turn the engine while adjusting the valves. A few days later a ticking noise showed up. I re-adjusted the belt tension and the ticking went away.

not the pulley / belt but more like engine :(
 

I have removed both the fan pulley and the AC compressor pulley and I still get the same loud tapping that seems to be coming from the engine (block) area. like very loud valve clapping. Doesn't sound good at all... :(

Chain tensioner failing?

I would definitely be checking for that. I would use a stethoscope to try and isolate where the noise is coming from. (a hose or long screwdriver held to your ear can work). If it's coming from the chain cover, it's time to take a look inside before it's big bucks.
Good luck, let us know what you find out.

I tried to use a stethoscope to locate the source of the noise, but it is so loud that it is hard to pinpoint the exact location; sounds like it's coming from either the right chain housing or the right valve cover.
<a href="http://s177.photobucket.com/albums/w233/frenchsailor/911/?action=view&current=CIMG3806.mp4" target="_blank"><img src="http://i177.photobucket.com/albums/w233/frenchsailor/911/th_CIMG3806.jpg" border="0" alt="Photobucket" style="width: 160px;"></a>

Probably should pull the valve covers first. Could be a broken valve spring, rocker shaft etc.
Then I'd pull the cam chain cover. Could be a broken chain guide. Either way I don't think you should run it till you check.

Thanks for all of the input. I do agree that I should not run the car under those conditions...
I guess I could put it up and as Gordon suggests start by pulling the right valve cover -my first thought was indeed a broken spring that could explain the banging -of a valve against a cylinder ?!?
Can this all be checked / done without removing the engine (e.g., rocker shaft?) ?
Thanks again.

1985coupe,
I don't want to scare you but this sounds much like the sound I had when I had a blockage in one of my oil feed holes to the camshaft lobe/valve rocker shaft area. There was no oil getting to the rocker surface and lo there was irreparable damage to the rocker and cam.....and a noise similar to yours at about a half engine speed.
Result? Complete engine strip down (as it was treated as a catastrophic failure to ensure nothing was left unturned to find the cause), reworked camshaft (stock) and new rocker....


Neil

That ain't sound good...
 

Neil, thanks for your input, and I'm afraid you might be right :eek:

Could you hear that noise coming distinctively from the right side though ?

Well, and yes I am really scared now :(

Please post what you find as the culprit

1985; Co-incidentally the noise was from the right side as it happens: over #5 cylinder. Turned out to be a small piece of latex rubber that got in the oil rail peventing the flow of lubricant to the area.

(PM me for the details of how it got there)


Neil

Thanks Neil... Let me guess about that piece of latex: glove ? I do use those to work on my car(s) too and I could see how one could tear up a piece that could fall in the wrong place.

I have sent the video to a Porsche mechanic (Star Auto, Timonium, MD) but they can't say what it is and would need to look at it -so I'd need to get it towed there.

If you're right about this and I would need the engine to be rebuilt, how much am I looking into spending ? I probably don't have the skills / tools / time to do it myself, but I just can't think about spending upward of $5K to get it back on the road -and I guess there would be a lot of things I'd want to change if I were to drop the engine -clutch, seals, etc...

I will definitely post more details as I get them (996:)

Thanks again.

1985; the cost is dependant upon the cause, and the condition of the rest of the engine prior to this. You don't say what kind of mileage you have on it or any other issues or big engine jobs done i.e. rings, valve guides etc etc.
A top end rebuild including machining work and the guides replacing will run around $4k depending on how much you do yourself and how much you sub out...

Neil

PS please keep us posted!!

overall condition
 

I don't have much info about the history of the car; I bought it 5 years ago from a dealer who bought it at an auction, and it now has 100K miles on it -got it @ 77K I believe. As far as I know the internals of the engine have never been touched and don't believe the case was ever open. I would definitely replace the valve guides as most of the time I get a big black puff of smoke at start-up -not always but 90% of the time.

I understand that the engine would have to come out... but then it'd be all down hill from there -did I mention my first gear synchro ? I have Wayne's 101 projects book and I guess I could follow the instructions on how to drop the engine - I do have a scissor lift in my 1-car garage. Unfortunately if I'd go that route I wouldn't be able to tackle this issue before Fall -I will be leaving in 2 weeks for France for the whole month of September.

Is there such a place where you just drop the engine and get it worked on ?
I am reluctant to bring it somewhere as I'd feel kind of trapped :(

Thanks for the advice, and hope I can find the best way to get around that problem.
If any of you know of a reputable shop that could do this kind of work -in my area, Baltimore-Washington DC- that'd be a great plus. I think I am more concerned about the work being done properly than the actual cost -although I really don't have unlimited funds at my disposal... But I'd rather pay more for a job done professionally.
I am willing to get my hands dirty though -I have tackled a few projects on the car including installing turbo tie rods, rebuilding front brake calipers, installing new wheel bearings, putting a new pedal cluster (my clutch pedal broke in 2!), replacing and adjusting the clutch cable, etc... but obviously nothing really major...

Thanks again ! Will keep you posted...

- Olivier

Olivier.....you're a pro!!!!
Seriously, you have it all in the right order.....I'm sure there are reputable companies by you that will take care of you.....just DON'T send your motor to MotorMe!ster....READ THE THREADS!!!

I have a very similar noise in my '85. It started after a hard drive last weekend (car parked since then).

Please let us know when you find out what the problem is Olivier.

Max.

Neil you're too kind... Really not a pro though... But I can follow instructions :)
Max, I'm sorry to hear you're having the same issue :(
I'm flying to France today and have not had the chance to look into that problem.
My plan is to start taking it apart once I'm back at the end of next month...
Will keep you guys posted.
Thanks to all !

- Olivier

Bon Voyage.

I'm back and back to square 1...
 

Well things are pretty much where I left them last time around. I have not yet started to dismantle my special piece of German engineering but will probably start doing this early next month -major deadline for me at the end of Oct.

Please share your personal experience if you do (did) happen to have similar issues.

I feel confident that with the help of this group of highly committed Porsche enthusiasts I shall find a way to the heavens of my air-cooled boxer engine :)

Thanks to all !

OK the weather is starting to get better so now would be the time to think about getting my 911 back on the road.
Not sure where that video clip went to here it is again:
CIMG3805.mp4 video by frenchsailor - Photobucket

I will soon start taking things apart and will document things. I have not yet been able to find a reputable mechanic who wouldn't rob me so it looks like I'll have to make the plunge and get my hands dirty instead of going sailing...

As usual any and all help is greatly appreciated.

- Olivier

I'm no expert in these things, but the accumulation of rust dust on the belts and pulleys and the jumping fan belt is interesting. Is it possible that something dropped down in between the engine cradle and the crank pulley and either bent or knocked the pulley loose so that it is rubbing on the cradle? Does the crank pulley run true?

I'll make sure to look for bits and pieces...
 

That's an interesting proposal and hadn't thought about something having broken down and fallen in the guts of the pulley / shafts arrangement and screw something up...

That knocking noise originates more towards the right side, that is quite certain, and its frequency seems about 1/3 or 1/2 that of the engine.

Wonder if there is a table somewhere that provides information about the frequency of the various moving parts of the engine as a function of engine RPM -a bit similar to what is provided for transmission gear ratio. That could maybe help pinpoint to a more likely culprit -short of a 3.2l 911 engine expert with golden ears. That is before I start taking that thing apart... Can't afford to screw things up...

Thanks again for the input -great suggestion.

- Olivier

After watching the video, and reading that you already ruled out the AC compressor by removing the belt, it's almost certainly a 1/2 engine speed tick. There is only one thing in your motor that spins half speed, and that's the cams.

Before pulling the motor, why not just remove the upper and lower valve covers? Maybe you'll find the cause right away. If it's a broken spring or broken rocker, it will be obvious when you examine the cam tower.

Also, while you have the valve covers off, check the head stud nuts. Make sure they are all there and torqued to spec. Sometimes a broken stud (or two!) can cause a ticking noise because the head and the jug are gapping and then slapping together when the piston moves through the cycle. Broken studs are not unheard of in the 3.2s, and worth a look.

Removing the valve covers will cost at most the price of a gasket kit. I'll be curious to know how it goes...

What brand of oil are you using?

Just a thought but maybe the Carrera Chain Tensioner Oil lines are clogged. I recall during my PPI that was one of the first things Tony Callas swapped in my baby.

procrastination soon to end...
 

OK I think I have collected enough information with the help of you guys to be quite ready to start taking things apart. Valve covers will be the first thing to go and I will report on my findings.

I have been using Castrol GTX High-mileage 10W-40 -the car has just under 100K miles. I live in Baltimore, MD, and the car is always garaged -so it rarely goes below freezing; summers are quite hot and humid... I drive maybe 3-4000 miles / year.
I have also been using Mobil 1 for a while and wanted to go fully synthetic but I am not quite ready to start chasing oil leaks... Although this should be the one I'd like to use.
Maybe I should start an oil thread -just kidding :D

Many thanks for all who contributed to this thread; I am about to take the plunge and get my hands dirty and will feel more comfortable knowing that help will never be very far, time-wise at least. This is once again great to have all of this concentration of P-car enthusiasts and experts.

I will report as soon as I have the valve covers off; might have to wait for this week-end -or next, or the one after... So many projects around and inside the house as well... Not counting recommissioning the boat after a loooog winter...

Thanks again -and you can always keep on making suggestions. Best to all ! SmileWavy

- Olivier

good luck! Hoping for the best for you and the car.SmileWavy

metal shavings in oil :-(
 

So I drained the oil and found a lot of metal shavings on both drain plugs.
I could only get about 4 quarts out though, mostly from the oil tank. I could retrieve more metal shavings from the case drain hole with my finger and attempted to help get those out by adding oil through the oil fill, but it was only accumulating in the tank and would apparently not make its way to the engine... Sounds like an indication of a major blockage...

Looks like I am in for a rebuild or a new engine... I'm quite devastated...

As usual any advice is greatly appreciated !

Best,

- Olivier

Olivier,

What happened? Were you able to fix it?

Shawn

I haven't had the time or money to get my 911 fixed. I am reluctantly putting it up for sale as is.
Bring me your best possible offer. From what I now understand we are looking at an engine overhaul / rebuild due to probably thrown out bearing -lots of small shiny bits of metal that are magnetic...
Vehicle located in Baltimore, MD.

A few years ago I had a similar sound coming my engine after an aggressive drive, during that drive I missed a shift and bent some valves. I really hope this is not what happened to you. Very expensive mistake !!

So sorry to hear that Olivier. I am in the same situation as you are...my wife is putting pressure on me to sell my car as it is (very similar problem as yours)...but I still cannot see myself without my precious!!!

I have the exact same noise coming from my engine as well. Did anyone find out what it was?