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So here’s an account of my air conditioning woes and a few questions.
A prior owner had removed the air conditioning from my car. I had the local dealer reinstall the system two years ago, both to make the car legal for the SCCA’s STX autocross class and because I had moved to New Mexico. I didn’t use the air that much, but it worked fine until a couple of weeks ago when the a/c compressor belt departed for parts unknown. I had the dealer install a new belt, but it only lasted a couple of days until it too went AWOL.
When the second belt bailed out, I noticed a length of 8mm all-thread protruding from the front of the a/c compressor bracket. It appears that the dealer secured the compressor to the mounting bracket with a length of all-thread with a self-locking nut on each end. The stud had taken a pounding, and had finally sheared off at the back ear of the mounting bracket. I suspect that solves the mystery of the missing belts. I replaced the all-thread with a 8 x 120 bolt, a couple of wave washers, and a self-locking nut. We (my son and I) put on a new belt that’s stayed in place for the past 1000 miles.
First set of questions: the a/c compressor bracket on my car looks nothing like the bracket shown in the real.oem diagram. When the dealer ordered it, they ordered PIN 82-39-9-404-494. It’s a black metal piece with two mounting ears for the compressor. Is this the “later model” bracket that I’ve seen referred to in some posts here? And is there any reason why I should care which version I have?
Second set of questions: we used a 13 x 815 belt. Stock is 12.5 x 810, but we didn’t have a stock belt available at the time. Anyone else using this slightly larger belt size? Any issues with it?
Third set of questions: shortly after the we got the belt installed, the a/c system succumbed to the frame rail cutting into the black rubber a/c hose. I gather from looking at posts here that that’s a common problem. Looking at the a/c setup on another 1990 M3, I can see two insulated hoses that cross the frame rail at close to right angles. But on this car, the black hose that got cut runs across the rail at a shallow angle. I also see that the other car has plastic clips on the frame rail that probably are meant to protect the hoses from the rail. Not surprisingly, there aren’t any on my car.
So is there some alternative to having the black hose running across the frame rail at a shallow angle? And what have others done to protect the hose from the rail? Do the plastic clips do the trick? Or is something more needed?
Thanks for any answers.
A prior owner had removed the air conditioning from my car. I had the local dealer reinstall the system two years ago, both to make the car legal for the SCCA’s STX autocross class and because I had moved to New Mexico. I didn’t use the air that much, but it worked fine until a couple of weeks ago when the a/c compressor belt departed for parts unknown. I had the dealer install a new belt, but it only lasted a couple of days until it too went AWOL.
When the second belt bailed out, I noticed a length of 8mm all-thread protruding from the front of the a/c compressor bracket. It appears that the dealer secured the compressor to the mounting bracket with a length of all-thread with a self-locking nut on each end. The stud had taken a pounding, and had finally sheared off at the back ear of the mounting bracket. I suspect that solves the mystery of the missing belts. I replaced the all-thread with a 8 x 120 bolt, a couple of wave washers, and a self-locking nut. We (my son and I) put on a new belt that’s stayed in place for the past 1000 miles.
First set of questions: the a/c compressor bracket on my car looks nothing like the bracket shown in the real.oem diagram. When the dealer ordered it, they ordered PIN 82-39-9-404-494. It’s a black metal piece with two mounting ears for the compressor. Is this the “later model” bracket that I’ve seen referred to in some posts here? And is there any reason why I should care which version I have?
Second set of questions: we used a 13 x 815 belt. Stock is 12.5 x 810, but we didn’t have a stock belt available at the time. Anyone else using this slightly larger belt size? Any issues with it?
Third set of questions: shortly after the we got the belt installed, the a/c system succumbed to the frame rail cutting into the black rubber a/c hose. I gather from looking at posts here that that’s a common problem. Looking at the a/c setup on another 1990 M3, I can see two insulated hoses that cross the frame rail at close to right angles. But on this car, the black hose that got cut runs across the rail at a shallow angle. I also see that the other car has plastic clips on the frame rail that probably are meant to protect the hoses from the rail. Not surprisingly, there aren’t any on my car.
So is there some alternative to having the black hose running across the frame rail at a shallow angle? And what have others done to protect the hose from the rail? Do the plastic clips do the trick? Or is something more needed?
Thanks for any answers.
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