My R4 compressor in 1980 300SD is leaking R134 to point where system won’t hold pressure. Does it make sense to try to open to replace shaft seal plus any other seals that might be causing problem, or just to buy rebuilt or new? If I do open to replace shaft seal, can I get by without special Mercedes tools? Also, any suggestions on best source for rebuilt or new?

Thanks
Bill

Sure you can. The R4 is not a "Mercedes" component.

Hello again Tango,

Are there other seals besides the shaft seal that I should be replacing and do I need any special tools? CD shows tool to hold front of clutch while removing nut, plus a seal remover/inserter. Also, have any idea where I can buy the seals?

Hello again Tango,

Are there other seals besides the shaft seal that I should be replacing and do I need any special tools? CD shows tool to hold front of clutch while removing nut, plus a seal remover/inserter. Also, have any idea where I can buy the seals?

Hello again Tango,

Are there other seals besides the shaft seal that I should be replacing and do I need any special tools? CD shows tool to hold front of clutch while removing nut, plus a seal remover/inserter. Also, have any idea where I can buy the seals?

I bought a rebuit R4 at Advance Auto Parts last summer for about $125. Working fine for 15+ months so far. I can't imagine that tearing one apart myself and replacing seals, valves, etc would be cost or time effective.

__________________
Bob
'82 300D Petrol B-G Metallic

The $125 was "clutch included".

__________________
Bob
'82 300D Petrol B-G Metallic

That is dirt cheap. I need one for my 240 and the cheapest I've found is $250. Did you tell them it was for a Mercedes or do you just ask for an R-4 compressor? Are they all the same?

Scott

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Scott
1982 Mercedes 240D, 4 speed, 275,000
1988 Porsche 944 Turbo S (70,000)
1987 Porsche 911 Coupe 109,000 (sold)
1998 Mercedes E300 TurboDiesel 147,000 (sold)
1985 Mercedes 300D 227,000 (totaled by inattentive driver with no insurance!)
1997 Mercedes E300 Diesel 236,000 (sold)
1995 Ducati 900SS (sold)
1987 VW Jetta GLI 157,000 (sold)
1986 Camaro 125,000 (sold - P.O.S.)
1977 Corvette L82 125,000 (sold)
1965 Pontiac GTO 15,000 restored (sold)

For the most part, they are all the same. There are some minor differences in the manifold connection (search for 'stepped port'), but these differences have nothing to do with Mercedes, and more with the manufacturing date of the compressor housing. Generally speaking, we are looking for early R4's with non-stepped ports, but stepped ports can be made to work with some fancy seal rings.

Advance is currenly charging $138 for a reman. Price has gone up.

__________________
Bob
'82 300D Petrol B-G Metallic