1984 300SD

Compressor (Harrison Mod#320) R4 type(?).

Compressor works O.K. for cooling, but makes very noisy metallic type noise,

My quandary is: Is it the compressor or the clutch that is causing it.

To get rid of the noise, I took the easy way out, for now, by removing drive belt. But I would like to fix it, or have it fixed.

I don't wish the expense and work of replacing the clutch just to see whether that's the answer or not.

Is it possible to make a definitive determination as to which is the problem, or is this a matter of being an experienced A.C. technician.

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1984 300SD TURBO DIESEL

Spin the idler pully on the compressor by hand. It should move freely, with out noise. If you feel resistance and hear some noise that could be your problem.

Spin the clutch and compressor by hand in the direction the engine spins. You should feel some resistance since you are spinning the innards of the compressor as well. If you hear or feel grinding, as you turn it, then it is your compressor. The Harrison compressors are known to go out. Seems as if GM engineered them that way. Remember GMC means General Mechanical Crap.

The clutch can operate electrically with out the belt, and you can then turn the whole assembly by hand.

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RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

99 W210 E300 Turbo Diesel, chipped, DPF/Converter Delete. Still needs EGR Delete, 232K

90 Dodge D250 5.9 Cummins/5 speed. 400K

Gone and still missed...1982 w123 300D, 1991 w124 300D

Put that belt back on and make sure its good and tight. For some reason, if the belts on these compressors aren't really tight then they make a noise like marbles bouncing around in a metal can. I've experienced this first hand on both of my cars. They made that sound at idle with the compressor engaged. Tightening the belt made the noise go away.

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Seth

1984 300D 225K
1985 300D Donor body
1985 300D Turbo 165K. Totaled. Donor Engine. It runs!!!
1980 300SD 311K My New Baby.
1979 BMW 633csi 62K+++? Dead odo

Does the noise occur with the A/C engaged or without. With the A/C OFF, the clutch on the compressor freewheels on its own bearing. If it is noisy with the A/C on and it's not the belt slapping, then the compressor bearings or internal other parts are shot. If the compressor is gone, DON'T use the A/C at all. The disintergration of anything internal on the compressor WILL contaminate the whole system. If you replace the compressor, replace the receiver drier also.

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My Truck.. 2007 DODGE, 5.9 Cummins, 6spd stick, 4X4. My car..1977 240D, OTHER WHEELS...1955 VW Oval window bug, European Delivery (Holland) with a 1700cc, 2 barrel, Porsche drum brakes. 1939 WILLYS Pick-up. 1967 Triumph 200cc Tiger Cub. 1976 Honda 550F 4cyl Motor Cycle.

Concur.

The R4's are notorious for making awful noises, but make sure the belt is tight and check your pressures with some A/C gages. Yes replace the dryer and expansion valve when you change the compressor.

I am doing another A/C job on an '85 coupe this weekend. Lots of greasy fun

Here is how to do your other A/C items if you need to:

http://dieselgiant.com/repairyourac.htm

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1981 300D 147k
1998 VW Jetta Tdi 320k
2001 Dodge Ram 2500 141k
1979 300D 234k (sold)
1984 300D "Astor" 262k(sold)
Mercedes How-To and Repair Pictorials
I love the smell of diesel smoke in my hair

A belated thanks to all who replied . Anyway, I had the belt re-installed and with the A.C. operating, I have the same old noise. With the A.C., switched off, I had the same noise.

What do you think: the clutch or the compressor, or both?

My Indy. mech. has an A.C. Precision Parts rebuilt compressor, But
the O.M. plate was removed. The Part number is AS 001796. I emailed them on July 15th., quoting their part number seeking info. on the original type, but I've had no reply ( snet another message to them to-day ).

Assuming this is a perfect fit, what ought to be done before installing it - I mean specifically flushing it out, etc., and filling with mineral oil.

All you valued help appreciated.

Padraig

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1984 300SD TURBO DIESEL