The new hose configurations are designed to attenuate the loss of R134a. since you are continuing with R12, this is not such an issue.

For cost consideration, replacing the hoses at a hydraulic shop will give you adequate service, just make sure to index the fittings before swaging...

New OE hoses will be more expensive, but would potentially give a better fit and look under the hood. Replacing hoses will shorten the metal line just before the swage, sometimes there is not enough metal to reuse the fitting.

Use the new style green o rings vice the original black ones.

No problem using the new oil, it's compatible with both refrigerants. Adding oil to the new compressor is critical, as is overfilling the system. Do some archive searching for the amounts of oil in various components, once you flush them, they will have to have the oil replenished.

Since the old compressor locked up, you will need to make sure that you thoroughly flush both the evaporator core and the condenser. The proper chemicals and air pressure will take care of this. Since your replacing the lines and the desiccant (drier), these two components are all you need to flush.

There have been several threads about compressors, the general consensus is to buy new, not rebuilt. The MB compressor is very similar to the generic GM, but threads are metric vice SAE, and there has been some discussion about the MB location being upside down vice the typical GM installation. (See archives)


You can also test fill the system with propane to check for operation and leaks... Static pressure is around 90 lbs.

Jim

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14 E250 BlueTEC black. 45k miles
95 E320 Cabriolet Emerald green 66k miles
94 E320 Cabriolet Emerald green 152k miles
85 300TD 4 spd man, euro bumpers and lights, 15" Pentas dark blue 274k miles