Fortunately the multiple pistons balance out the vibrations
1973 AC conversion Compressor Issue
- Thread starter pickman
- Start date
Bosch
I removed the earlier adapter bracket and went with those recommended by SFDon from the e28 site. They put the Sanden in almost the same mounting position as the OEM compressor. Took more effort to get it all in, but it looks like it’s going to work just fine and everything clears very nicely.
Again, this is on a stock e28 with M30. Your mileage may vary. Picture is before all bolts are in..
Ed
Again, this is on a stock e28 with M30. Your mileage may vary. Picture is before all bolts are in..
Ed
I have my conversion 99% complete and would like to pass along one item that made determining the hose length very easy. I purchased 5/8 ID vinyl hose (about $8.00) and all the fittings. Using the hose (see attached) it was very easy to cut and work to the desired length. The old adage (think twice cut once) really did not matter as any mistake was easily corrected. All my hoses once constructed fit perfect. My clearance issue was just a matter of re-positioning the radiator and the multiple brackets ended up with .75 inch clear.
I'm finding out that between the twisty country roads up here, the inspiration those provide to indulge in spirited driving and possibly some flex in the radiator bracket rubber, this issue can become a serious problem.
Here is what happened to me last weekend.
With an immense does of good fortune, this happened right as I was parking my car at the Novato cars and coffee... and not during the one hour drive there or, worse, during the 13 hour drive from LA to NorCal a few months ago. And the culprit is... the Sanden compressor pulley. Even through there is about 1/4 inch clearance between it and the hose at idle, during driving, things tend to move more then that. The pulley cut the clamp in half. Fortunately the hose was only scored and not cut. Lucky for me, Lisa 02p (who was parked next to me) called her friend Kacey from Bill Arnold BMW, who was also attending the cnc. She immediately drove to her shop, got me a new clamp, installed it and, thanks to her help, I was able to get back home... albeit at a much more measured speed. Those two women saved the day!
Here is what happened to me last weekend.
With an immense does of good fortune, this happened right as I was parking my car at the Novato cars and coffee... and not during the one hour drive there or, worse, during the 13 hour drive from LA to NorCal a few months ago. And the culprit is... the Sanden compressor pulley. Even through there is about 1/4 inch clearance between it and the hose at idle, during driving, things tend to move more then that. The pulley cut the clamp in half. Fortunately the hose was only scored and not cut. Lucky for me, Lisa 02p (who was parked next to me) called her friend Kacey from Bill Arnold BMW, who was also attending the cnc. She immediately drove to her shop, got me a new clamp, installed it and, thanks to her help, I was able to get back home... albeit at a much more measured speed. Those two women saved the day!
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It was great to meet you Bo! Welcome to the North Bay! I’m glad to have been of some help and glad to hear you got home safely!
Lisa.02p
Yes that's what happened to me before I re positioned my mounting bracket and moved the radiator. Hope .750 inch clear is enough? Good to hear your journey had a good ending.
Every situation is a little different but possibly a shorter belt would move the pulley over some. I use the E28 setup.
I did this to mine.
I did this to mine.
I like this idea. It seems like it would be relatively simple test before switching to a different bracket system all together.
I currently have a 13x900 belt which, I am guessing, means 13mm wide x 900mm long. I can get a 13x810 in 2 days on Amazon. Am I correct to think that this would work better? The compressor is currently adjusted at the outer limit of the bracket. The available "opening" as seen in the pic below is 16mm which seems a decent amount of room.
Hopefully this will do the trick for you.
I don't remember my specific sizes without going and looking.
The problem I remember with mine was I got 2 shorter belts. I could not get the shortest one on the pulley's at all and had to use the next shortest.
Helped the problem but still close.
I don't remember my specific sizes without going and looking.
The problem I remember with mine was I got 2 shorter belts. I could not get the shortest one on the pulley's at all and had to use the next shortest.
Helped the problem but still close.
Bo, 90mm is a lot, around 3 1/2”, so it would shorten the length 1 3/4”.
Best to get the Gates catelogue and buy a couple sizes smaller from the local autoparts store and keep the one that works and return the others
Crap, you're right! I kept thinking it was 9mm... Doh! Yes, 90 is way too much!!!
Just changed it to 13x875.
Thanks Chris.
I went to my local small engine repair guy he has a complete line of Gates belts, borrowed several sizes and found the lest length I could assemble on the pulleys. Also the re positioning of the Engine brackets for the compressor allowed a bit more room to the radiator.
Hmmm. I tried to fit a shorter belt on but I could not even get the current one off! The problem is that when I loosen all bolts I can only rotate the compressor half way towards the engine. There is something that keeps it from going further although I could not see what it is.
So another thought came to mind. For some reason the V of the pulley is very deep. See middle pic in post 29 above. It extends almost a quarter inch beyond the belt itself. I wonder if I could grind it down a bit by running the engine and holding a metal file on the outer edge of the V to reduce the pulley diameter a bit. Has anyone done that?
So another thought came to mind. For some reason the V of the pulley is very deep. See middle pic in post 29 above. It extends almost a quarter inch beyond the belt itself. I wonder if I could grind it down a bit by running the engine and holding a metal file on the outer edge of the V to reduce the pulley diameter a bit. Has anyone done that?
Bo, Don’t go there!
I agree with Chris.
Some of those brackets have a limit stop to them where the compressor bolts to the bracket.
Also the hoses exit the compressor at the top on some and the hose can hit against the block.
There are so many variations I can't remember them all.
You would probably have to unbolt the compressor to get a good look at how it mounts.
Some of those brackets have a limit stop to them where the compressor bolts to the bracket.
Also the hoses exit the compressor at the top on some and the hose can hit against the block.
There are so many variations I can't remember them all.
You would probably have to unbolt the compressor to get a good look at how it mounts.
Belts come in different widths which affect depth so try to find one that fits the pulley
Haha. I had a feeling it wasn’t going to be that easy...
Out of curiosity what makes you say that? My main concern was that it could throw off the balance of the pulley. But if you make it spin on the compressor, using it almost like a lathe, it *should* keep the balance correct, shouldn’t it?