Definitely go with the mineral oil. I had a fun time finding someone who had the correct mineral oil but I wound up with the same stuff you have there in the 32oz bottle. For leak testing, I would use propane because it is cheap and I have it ready. It's probably not dry and I don't know if a leak detector will sniff it but an ounce or so of R12 mixed in should do it. I'll probably catch hell for that suggestion but then again, some people run propane in their A/C systems and get good results. Guys, spare me the lecture, I know A-Z argument about propane but I am only suggesting he leak test with it given he has R12 which is the best option.

I just re-did my A/C in the 300SD and it is much better than it ever was with R134a. It's not blowing 40F at idle with 105F OAT but I would love to see an MB car that is. I also need to install a larger condenser fan which will help with idle vent temps. I'm not sure where in Dallas you are but if you need help, let me know.

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1991 F250 super-cab 7.3 IDI. (rebuilt by me) Banks Sidewinder turbo, hydroboost brakes, new IP and injectors.
2003 S430 - 107K
1983 300SD - Tanoshii - mostly restored ~400K+.
1983 300SD - Good interior. Engine finally tamed ~250K.
Monark Nozzle Install Video - http://tinyurl.com/ptd2tge

I've just realized that the PO did some modifications to the AC system. The high-side hoses where fitted with screw-on ferrules to attach the rubber hoses, instead of permanent crimped-style ferrules, similar to the attached pics. The hard lines are still intact, but the fittings were brazed on or fitted with adapters. It's kinda cool, cause now I can replace just the rubber portion of the high-side, not the whole thing.

Will an AC shop sell me just the rubber hose by the foot?

Are these screw-on hose ferrules better than the crimped style?

It would be great to have someone make the oil cooler lines this way, so all that needs to be changed is the rubber when it goes bad.

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cbjukraine
'84 300D

That certainly is unique. I have never seen such a thing on a car, especially for A/C lines. You may have to get the hose from a hose and pipe shop. There is a place in Lewisville off 121br called Stewart Hose and Pipe. I have been referred to them by several people for things like what you are asking. It looks like they carry a lot of heavy duty hose like on the A/C system.

Stuart | Hose & Pipe Company

__________________
1991 F250 super-cab 7.3 IDI. (rebuilt by me) Banks Sidewinder turbo, hydroboost brakes, new IP and injectors.
2003 S430 - 107K
1983 300SD - Tanoshii - mostly restored ~400K+.
1983 300SD - Good interior. Engine finally tamed ~250K.
Monark Nozzle Install Video - http://tinyurl.com/ptd2tge

You have braided hoses? I haven't seen braided hoses on factory MB a/c systems since the 114/115 days. Those were reusable fittings. I can't remember the brand name for them. If you have these type fittings, when you get a leak at the fitting, you simply use wrenches to take it apart and then cut an inch or so off the line with a carbide wheel and thread it back together.

Stratoflex, that was the name of those fittings.

If you don't have Stratoflex, reusable fittings, then simply get new ferrules, a length of the correct size hose and crimp it in place on your existing fittings. The hose comes in numbered sizes and is quite readily available at auto a/c shops, or probably also at your local residential/commercial ac supply house.


WOOPS! After writing the above I saw that you already posted that you have Stratoflex fittings. Never mind!

And yes, these are better than the original crimp fittings. The car makers went to crimp fittings because they are cheaper.

__________________
2001 SLK 320 six speed manual
2014 Porsche Cayenne six speed manual

Annoy a Liberal, Read the Constitution

No reason not to make oil lines with these fittings. Just go to your local hydraulic hose shop and they can sell you what you need.

That said, my experience has been that the oil cooler lines don't need replacing but maybe once in the life of the vehicle. Making these lines would make them easier to freshen up the NEXT time they need it, but that time will likely never come during your or the cars lifetime.

__________________
2001 SLK 320 six speed manual
2014 Porsche Cayenne six speed manual

Annoy a Liberal, Read the Constitution

I went to McCains today to see about buying some new hose to replace the braided hoses on the high side. They said the stratoflex screw on crimps were utter crap. They are prone to leaking and crimped hoses were way better. They could be blowing smoke up my butt to sell me a job, but they showed me the goodyear barrier hose they use, and I can't imagine how it would work with the screw-on crimps. I wouldn't be able to attach it. Way too tight of a fit.

So I went to the junk yard and found a very good condition high side hose. I'm either going to use it as is or get McCains to fabricate hoses that I can disconnect at the compressor and at the oil pan, kind of like the one that runs from behind the alternator to the condenser.

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cbjukraine
'84 300D

No, if McCain's tells you that, you can bank on it. They are good people. I haven't had Stratoflex lines since the 114/115 days. I liked them because when they DID leak, it was a quick and free fix. If Mark tells you they don't work well, then he has a reason and a good one.

Mark McCain will do good work for you whatever you decide to do.

__________________
2001 SLK 320 six speed manual
2014 Porsche Cayenne six speed manual

Annoy a Liberal, Read the Constitution

Hey John,

I happen to run across this on the EPA website.

What You Should Know about Refrigerants When Purchasing or Repairing a Residential A/C System or Heat Pump | Ozone Layer Protection - Regulatory Programs | US EPA


"any" appears to be an absolute here. Just so that we all don't get in trouble for venting, do you have a copy of the reg about using it for testing?


.

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1983 123.133 California
- GreaseCar Veg System

it falls under the hose venting allowances.
the passage you are quoting is to keep those who would dump a charge.

a proper recharge involves reclaiming the refrigerant from the system itself, and closing the valves between the reclaimer and the tank. then the hoses must be purged. and the hose contents are allowed to purge to the atmosphere. as long as the volume is not above 4oz. (I've got some hoses that are 50 feet long... I have to reclaim them...)

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!