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Join Date: Mar 2005
Location: Hill Country, TX
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Yesterday I started my car and the engine sounded like a bucket of bolts. A frighting loud knocking noise coming from around the distributor or lower left side of the engine.
I stopped the engine and started it again. Same noise. Started and stopped again, no noise idling but the noise would increase with revs. I had the alternator rebuilt a couple of weeks ago so I removed the belt, same noise, only with revs. Stopped & started again, no noise. Today I changed the oil, no metal. Swung by the mechanic, still no noise. They think it's the chain tensioner but weren't sure why it would stop making the noise. I've seen plenty of threads describing the same noise but the chain tensioner noise doesn't seem to go away before engine failure and often quits at higher rpms. Also saw some mention of muffler baffles. This is my daily, I'm listening to the engine at every stop, not really enjoying the ride. Still no more noise but need your thoughts/comments. Thanks,
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pat 18,000mi a year 84targa Last edited by Pat Crellin; 05-09-2005 at 07:56 PM.. |
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The silence is deafening.
I could use some help here. I'm not sure to drive & wait or have the wrench start looking for something.
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pat 18,000mi a year 84targa |
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Adrenaline Junkie
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I'm still the noob here but I'll step out on a edge and guess it might be a loose cam chain?
I wouldn't run that at all. Flat bed it to your mechanic. ![]() |
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Now in 993 land ...
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These are the chain tensioners. No muffler bearings.
![]() Seriously. The chain tensioners can be moody and sometimes work and sometimes not. Needless to say, they won't get any better with time, so I'd go and change them. I have heard a bunch of failed tensioners now, and your symptoms sound exactly like it, including the dependency on the revs. George |
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Adrenaline Junkie
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Damn, I'm good!
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Join Date: Nov 2004
Location: Greater Metropolitan Nimrod, Oregun
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youp, bucket of bolts = chain tensioners
Do NOT drive it. Got a spare $400 sittin' around?
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"A man with his priorities so far out of whack doesn't deserve such a fine automobile." - Ferris Bueller's Day Off |
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Join Date: Oct 2002
Location: Indianapolis, Indiana
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I had a similar noise with my 80sc when my tensioners failed. I was running guards so there was not a total catastropic collapse.
The similiar intermittant noise I heard was a chain guide rail that was broken by the loose chain. It was knocking against the chain housing. I would certainly check out any knocking noise from that critical area of the engine.
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1980 911 SC |
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Location: Black Rock, CT
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Yeah....
I pulled easilty away from a stop light, and there was a sudden, sick, and loud sound that wo me resembled a collapsing extension ladder. Then silence. In there was also the sounds of pistons and valves hitting each other, as my chain tensioner had failed, and the rest was expensive history. You dodged a bullet. rent a car. Open her up and have a look!
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Jake Gulick, Black Rock, CT. '73 yellow 911E , & 2003 BMW M3 Cab. Ex: 84 Mazda RX-7 SCCA racer. did ok with it, set some records, won some races, but it wore out, LOL[/B] |
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This is great, I just had the t.ranny & clutch rebuilt.
Didn't think this happened on the 3.2. But you guys think I might have lucked out, I drove it to work. I don't know if it's intermintent, it hasn't happened again. I drove it yesterday, probably 60 miles. My wrench said to go ahead and drive, call if it happens again. Maybe I should find another wrench, it's such a sad sounding noise, I can't imagine it just goes away. So at this point it's not hugely expensive? This is not a job for myself. thanks
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pat 18,000mi a year 84targa |
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How big of job is this? Does the engine have to come out?
The engine sounds perfect right now. thanks
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pat 18,000mi a year 84targa |
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Location: Duluth, MN USA
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Check out the tech article on upgrading to pressure-fed tensioners (which you already have). No engine drop. It should give you an idea of how difficult this job is. BTW, I have not done this so cannot provide personal experience with the job. Good luck.
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Tim 83SC Coupe |
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http://www.pelicanparts.com/techarticles/911_carrera_chain_tensioners/911_carrera_chain_tensioners2.htm
Oops. I meant to include the link to the article. Sorry.
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Tim 83SC Coupe |
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Thejob is a cakewalk, and the parts are cheap compared to te consequences.
Even if we are wrong, hey- we weren't there, we didn't actually hear it!...and it is something else, replacing them isn't the end of the world, not a huge waste of money. NOT replacing them tho'...and having the chain skip a few teeth will run you over 5k. There is no guaratee that that willl happen either, but....
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Jake Gulick, Black Rock, CT. '73 yellow 911E , & 2003 BMW M3 Cab. Ex: 84 Mazda RX-7 SCCA racer. did ok with it, set some records, won some races, but it wore out, LOL[/B] |
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Join Date: Feb 2000
Location: Lacey, WA. USA
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It's a slight PITA, but no engine drop is necessary. I'd suggest getting one new pressure-fed tensioner and replacing that driver's-side tensioner. Perhaps when you changed oil, the oil bled out of the tensioner, and now it's quiet because there's oil in it again. But don't trust that. The oil is only expected to dampen the movement of the tensioner. The actual chain tension comes from the spring inside the tensioner, and that may have failed. If you stop trusting a $200 tensioner in a $10,000 engine, then this is my suggestion.
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Man of Carbon Fiber (stronger than steel) Mocha 1978 911SC. "Coco" |
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Now in 993 land ...
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If the noise is gone now, things are working currently. I have a friend who has had such an intermittend noise once after changing his oil. If yours started independant from any work on the engine, I would still go in ASAP and spring in for a couple new tensioners.
While this isn't hard to fix for a half way experienced DIYer, I would not recommend it for a novice. Looks like you should live amidst folks that have worked on their engines plenty. If you are pretty new to wrenching on cars, buy some beer and pizza and have a couple volunteers over at the point in time when the tensioners are actually changed. If you do not keep the chains stretched swapping tensioners, you can loose cam timing and wreck your engine. So, this also means the volunteers get the beer only after the new tensioners are in! ![]() I would think a shop should charge about 5 hours or less to do the work? You can buy a lot of beer and pizza for that. While you are at it you may want to upgrade to the better oil line. I think the later tensioners had an oil line that was held with a small bracket, to avoid fatigue of the metal line from vibrations. George Last edited by aigel; 05-10-2005 at 06:42 AM.. |
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Wider is Better
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Quote:
Hydraulic tensioners are LESS likely to catastrophically fail than earlier models. As I understand, the advantage of a hydraulic tensioner is that you would hear noise before catastrophic failure occurs. Maybe it's not the tensioners, but you will not know that until you replace the old ones. As for me, I would want to know.
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Wider is Better |
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How many miles on your 3.2L??
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"A man with his priorities so far out of whack doesn't deserve such a fine automobile." - Ferris Bueller's Day Off |
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Thanks for the input guys. It was the left tensioner. I'm having them both replaced and picking the car up tomorrow.
The car has 140,000 miles on it. How often does this happen on the 3.2? Should I have the wrench look for anything else?
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pat 18,000mi a year 84targa |
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