924Board.org

[Al]

No joke, I have had three different exhaust places work on it. One worked on it twice, and the other two tried as well with no luck. The converter has a ten year warranty, however, has broken on the front seam and on the back. Twice the pipe and muffler physically fell off of the car while driving down the road. Here is the question. What could cause the welds to break so many times? Bad motor mounts, too much torque, or poor workmanship?
What are your ideas?
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1981, 924

[968rz]

missing or broken exhaust mounts/hangers
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Rick
79 924 coupe Petrol Blue 3spd auto (wife's DD)
93 968 coupe Amazon Green 4spd Tip (my DD)

[El Chato]

Cant tell you what it migth be, but I would surely secure them good, I had the same problem happen after I droped the tranny to change the bushings on the shifter, then it started spliting at different points, then I took it to have it properly welled the guy did it but then he did not used the proper bolts, and then like a week ago they got loose or something the pipe felt between the cat and the silencer.

so what I did is I got a platem my father (toolmaker) and me (having some desining skills and machining as well) made the flange that bolts on the bottom, and used a 2 inch pipe all the wall from where the cat which I took out to the hanger behind the silencer which I also took out. now it sounds good so far,

so I will look for that piece of pipe that was loss and from this one we made add another flange and make an easy bolt replacement for the CAT, and then add another muffler along the way.











I know that the diameter of the pipe has to do with how fast the fumes escape and the hot it gets, I believe that smaller is hotter but faster and bigger is colder and slower, so maybe using this migth help to replace the pipe and with help other member get the proper better size
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1979 924 N/A, Snail Shell
1980 924 N/A
1976 924 N/A

It may be that your whole purpose in life is simply to serve as a warning to others.

Today's weirdness is tomorrow's reason why.

[Chrenan]

When was the last time you replaced your motor mounts?
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1987 951 - M193 Version for Japan

[Smoothie]

Motor mounts and transmission mounts... But, in OE form, the exhaust is rigidly attached to the motor, torque tube, and transmission so all that stuff moves as one. -So make sure it's all attached OE style, and that all exhaust to torque tube and transmission brackets are there (no aftermarket exhaust-to-body hangers). If all the OE brackets are there already, maybe add one or two (again, rigid type) before and/or after the cat, attaching to the torque tube.
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"..it's made in Germany. You know the Germans always make good stuff."


'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

[Al]

Thank you for the responses. I crawled under the car tonight and took a look at the hangers. All the hangers and the rubber are there. The hangers themselves are not factory but were constructed to resemble them. As for the motor mounts, I have suspected them for a long time. I haven't replaced them and I am sure the previous owner hadn't either. I think that I am going to start there and see where that leads to.
Thanks
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1981, 924

[Brockoli]

driver side motor mount is NLA. The passenger side is tho. Try partsheaven.com or nineapart.com for a used one. You can buy an aftermarket driver side mount but I remember reading somewhere (probably here) that they significantly increased vibrations
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'80 924 M471,Wideband O2, Full coilover susp,23/19 sways,Bilstiens,KLA Strut Brace,Roll Bar,Test Pipe,BBS RS, Willwood BBK

25% of a '87 944 Chumpcar http://straightpipe.ca/forums/showthread.php?t=2454

'79 924 Sebring Edition(Sitting)

[Al]

Thanks for the tip. I have been all over the web looking for the motor mounts. I placed an order today from Automotion.com for a new passenger side mount, (I hope that they have some in stock). Another place that I may have to try is the swap meet at Hershey PA. The one thing that worries me, is the used one any better than the one that I have on the car?
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1981, 924

[Brockoli]

I got a good used one from partsheaven for a reasonable price, i cant remember how much, maybe $75 for both of the mounts. So far so good, the mounts have about 7000km on them and no trouble yet.

The driver side mount fails when the rubber inside the mount seperates from the metal outer lining. Its pretty easy to tell if your motor mount is shot, especially on the driver side. If the rubber seperates the mount will collapse. There are holes in the rubber mount and if they are squished flat you know its garbage. Not to mention the increase in vibrations.

Be careful if you buy on ebay, I saw a pair of mounts on there and the driver side was starting to seperate. I saved the picture and zoomed in to clearly see the tear. I couldnt tell how much it was seperated but the mount I got form partsheaven didnt have a single tear in it.

As a band-aid on my old motor mount I used an old semi mud flap i had lying around. I cut strips of rubber out of the mud flap and used a bench grinder to shape them. I carefully test fit them in the holes of the motor mount. I got the rubber strips to fit tight in the holes on the mount. There are 4 holes in the driver side mount. For the to upper holes I used to strips and for the bottom 2 holes I used a horse shoe shaped rubber piece. I used supper glue to glue the strips in the motor mount. I did this because the oil pan was rubbing on the front cross member because my driver side mount was completely collapsed. When the car was idling it made a knocking noise This worked for awhile till I got my new(old) mounts form partsheaven.
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'80 924 M471,Wideband O2, Full coilover susp,23/19 sways,Bilstiens,KLA Strut Brace,Roll Bar,Test Pipe,BBS RS, Willwood BBK

25% of a '87 944 Chumpcar http://straightpipe.ca/forums/showthread.php?t=2454

'79 924 Sebring Edition(Sitting)

[Nobbi]

One thing seems to be clear, you have some typ of tension in your exhaust system, if youre lucky its gone with the motormount replacement, but that wouldt surprise me.My guess,the exhaust system is not installed as it should be. It should "swing" freely in its rubber hangers, plus, in the right places.Try to get someone with a car for reference.

Nobbi
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NA 924 - april/1977- 4-speed-audi gearbox.
500.000 km with fun.....and new toy:Porsche 944 S2 Cabriolet.Other car Daimler c-class cabby,brandnew..Plus : DEUTZ 4005 tractor Built 1967

[Al]

Thanks for the advice. I noticed that when I loosened up the bracket supporting the muffler, there was tension. Not a lot, but maybe that had something to do with it. I am going to check into a muffler hanger bracket as well.
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1981, 924