Bypassing a/c compressor with shorter serpentine belt? - PeachParts Mercedes-Benz Forum

LCA078 · #1 07-22-2010, 12:42 PM

My '93 E250 with 2.5L TD is at the Italian mechanic where they figured out my car wouldn't start because of the bad a/c compressor. The mechanic called around today looking for an a/c compressor, filter-dryer, etc. to get my a/c system working again. The message he left on my cellphone was "parts are more expensive than i thought. come by tomorrow to discuss estimate."

So I'm thinking I may have to order the parts from the states and have them shipped to my APO mailbox where I can install them at the base self-help garage. My question is can I drive the car with shorter serpentine belt that bypasses the a/c compressor? I know other cars can do this but wanted to know if there was any issue with my car?

Any info tonight is appreciated before I go in tomorrow morning to the mechanic. I've already priced compressors online in the states and it looks like $300 is average.

Billybob · #2 07-22-2010, 01:51 PM

Quote:

Originally Posted by LCA078

My '93 E250 with 2.5L TD is at the Italian mechanic where they figured out my car wouldn't start because of the bad a/c compressor. The mechanic called around today looking for an a/c compressor, filter-dryer, etc. to get my a/c system working again. The message he left on my cellphone was "parts are more expensive than i thought. come by tomorrow to discuss estimate."

So I'm thinking I may have to order the parts from the states and have them shipped to my APO mailbox where I can install them at the base self-help garage. My question is can I drive the car with shorter serpentine belt that bypasses the a/c compressor? I know other cars can do this but wanted to know if there was any issue with my car?

Any info tonight is appreciated before I go in tomorrow morning to the mechanic. I've already priced compressors online in the states and it looks like $300 is average.

The quick and dirty fix you could try is to simply disconnect the electrical current to the AC compressor electro-mechanical clutch, the connector is located on the top of the AC compressor. That would allow the clutch to remain dis-engaged and free-wheeling in place. Of course this will only work if the clutch is not defective and capable of disengagement which is its normal unenergized state. You could then drive the vehicle without further modification until you decide what you can do about the AC system, good luck!

LCA078 · #3 07-22-2010, 02:32 PM

The a/c compressor is really hard to turn by hand when de-energized (let's just say it's locked up) so the clutch and internals are fried. Compressor won't free-wheel at all.

I'm new to the car (less than a month) and it's stuck at the mechanic so I can't look at it to determine the belt thing. I don't know if it's possible to run a shorter belt or just run without a belt at all. I can't even remember if my model was an eletric cooling fan or driven by the belt. I know the power steering will be inop but I can live with that for a couple days while parts arrive in the mail.

Just trying to have a plan in place in the morn so I don't have to leave my car at the mechanic...

Billybob · #4 07-22-2010, 03:00 PM

Quote:

Originally Posted by LCA078

The a/c compressor is really hard to turn by hand when de-energized (let's just say it's locked up) so the clutch and internals are fried. Compressor won't free-wheel at all.

I'm new to the car (less than a month) and it's stuck at the mechanic so I can't look at it to determine the belt thing. I don't know if it's possible to run a shorter belt or just run without a belt at all. I can't even remember if my model was an eletric cooling fan or driven by the belt. I know the power steering will be inop but I can live with that for a couple days while parts arrive in the mail.

Just trying to have a plan in place in the morn so I don't have to leave my car at the mechanic...

Well if by de-energised you mean with the electrical connector physically dis- connected and removed from the compressor, this quick and dirty will not help! Malfuncioning ACC electricals can produce an errant AC clutch current causing a failure to disengage, hence the necessity of making the physical disconnect to be certain.

Running without a belt won't work for more than a short time as the water pump will not be circulating coolant and the alternator will not be producing current. Good Luck!

Billybob · #5 07-22-2010, 03:32 PM

Here's some info that might help you out!

http://www.w124-zone.com/downloads/MB%20CD/W124/w124CD1/Program/Engine/602_603/13-1202hw.pdf

Lists for the 602.911/912/961/961 without AC a 2030 mm belt, can't say that you will be able to get the belt to run in place with the AC compressor still installed but maybe it will or maybe you can just disconnect and remove the AC compressor and instal the short belt.

aaa · #6 07-22-2010, 08:16 PM

The shorter belt from the manual goes thru where the compressor goes. I'd think you'd have to remove the compressor to route it properly. My next thought is ditching the steering pump too with an even shorter belt but the tensioner probably isn't amenable to that.

LCA078 · #7 07-23-2010, 12:31 AM

Billybob- Thanks. That's exactly what i was looking for. But like AAA said, it looks like the a/c compressor is in the way and has to be removed anyway.

Hmmm... I'm off to the mechanic in a few minutes so we'll see how much he'll try and stiff me.

holtonmusicman · #8 07-23-2010, 02:19 AM

Where are you located?

LCA078 · #9 07-23-2010, 01:41 PM

I'm located in Vicenza, Italy which is about 40 mins west of Venice. First time in my Army career I can truthfully say that I love where I'm living!

But, for my car...my mechanic gave me the quote for a new a/c compressor, filter/dryer, and installation: 900 Euro. That equates to about $1200 USD. He was very apologetic and showed me the breakdownd. Cheapest he could find a compressor for was about 500 Euro, a filter/dryer for about 70 Euro, R-134 was 40 Euro a pound, etc. He already pulled the compressor and offered to put on a shorter belt so I can drive without a/c. Looks like I'm gonna order parts from Napa or such in the states and have them shipped over.

I'm ASSUMING that the European 2.5L TD a/c compressor would be the same as an American 300D?!? Anyone know different? I have access to a pretty good self-help garage on base, I just need the parts.