For those of you who have followed my experiences with my 180K 300E, here is another chapter. I am not complaining, but in sharing this, I hope that others will learn of the complexities, expense, and pitfalls of the 124 AC system.
When I bought the 300E in April, it had a frozen compressor, and no power to the compressor. I decided to convert it to R134 since I really enjoy the car and want to keep it around for a while.
Here is a summary of what I spent and what happened.
Rebuilt Behr Compressor (incl clutch) - $465
Drier bottle and switches - $110
From Performance Analysis
Manifold pipe - $400
Expansion valve, oil, seals - $120
My plan was to install all of the new components, and take it to a shop for flushing and servicing.
I replaced the compressor, after following the directions to add oil. The Behr unit is shipped without a speed sensor, or manifold pipe connector, so I installed those from the old compressor. Installed the compressor to make the car driveable. So far so good.
With the parts installed, the car was ready to go to Silver Star Motors for flushing, evac, and charging. Shortly before took it there, I discoved that the compressor had leaked a quantity of oil. The shop determnined that this was caused by an improperly installed speed sensor. The result was that the shop R/R'd the compressor, drained the oil, and refilled it. In the course of doing this, they discovered that the belt tensioner, and shock absorber were shot, and replaced them. They also replaced the hose from the condensor to the drier. Then they flushed the system until they quit getting metal out, installed the expansion valve, evac'd it, and refilled it with R134.
Total bill at Silver Star - $1127 ($630 labor, $497 parts and misc.)
Total cost for entire job - $2,342.
Not complaining or feeling screwed. Just want to make others aware of what they are getting into when they undertake major repair to a 124 AC system. I could easily have added $1000 to this total by using all Mercedes parts.
Lessons learned -
Be damned careful to get the compressor speed sensor on correctly and make sure it does not leak before installing the compressor.
System now works great - good luck to all who attempt this.
Falls Church VA
'86 300E 5 speed
'95 C220 (wife's car)
'98 Porsche Boxster
Past: '79 280E, '82 300D (18 yrs), '77 240D,