Can the a/c condenser be flushed in place on '87 300SDL? - Page 2 - PeachParts Mercedes-Benz Forum

leathermang · #16 09-08-2016, 12:10 PM

This might be a good place to recommend... particularly for those who have PFlow condensers .. which some suggest are not effectively flushable due to the small size of their tubes.. which I do not know is true or not..
BUT in 1987 when I put an AC into my air powered Karman Ghia ... by using three different ' add on AC units ' normally added under the passenger side of the dash....
I went to my local specialty AC shop ( before the internet ) .....and added an inline filter.. on the high side... before the condensor.... if one wants to prevent the trash produced by a ' black death ' by the compressor.... this should save the condensor from getting trash in it... it would still need to be flushed of burnt oil... but actual physical trash should be caught...

https://www.google.com/#q=automotive+inline+ac+filter

Demothen · #17 09-08-2016, 12:26 PM

I am saying that you absolutely can flush using a can of flushing agent without removing the condensor or building new plumbing. I have done so. Removing the condenser would make it easier, but is not absolutely required.

jay_bob · #18 09-08-2016, 02:57 PM

I agree that it is possible, so long as the exit tube on the bottom angles down or straight out. If the tube goes up you have a trap situation just like a sink drain.

compress ignite · #19 09-08-2016, 11:07 PM

That's why we have Shop Vacs and Duct tape!

Push AND Pull that stuff through !

I've used a separate 5 gallon plastico bucket as a receiver for the Liquid
With a homemade filter so that the shop Vac can't suck "Flush".

I'm only leaving it up to demonstrate how much trouble you can
get into IF youse doan Knows whats youse Doin !

PLEASE see funola's CAUTION below!

funola · #20 09-08-2016, 11:22 PM

Sucking the flush through is a great idea. Using a shop vac not so much and dangerous with the low flashpoint of most AC flush. It could be done safely with an empty 30 lb freon tank evacuated to suck the flush through. No spills whatsoever! With "ignite" in your sig I thought you should know better than to use a shop vac lol.

Another great benefit with a sucker tank besides no worry of sparks is no loss from evaporation of the low flashpoint flush. Perfect to use with ethanol.

funola · #21 09-08-2016, 11:44 PM

Another idea is to use the condenser as a sucker tank. Just plug one end and put a hose with a ball valve on the other end of condenser. Pull a vacuum in condense. Stick ball valve in flush container and open ball valve. Same idea as an air lift to fill coolant system. This completely fills condenser to let it soak. Blow out with compressed air to reclaim and filter the flush and repeat.

compress ignite · #22 09-09-2016, 11:56 AM

'Tis a wonder I'm not living in a Burn ward.

For someone who (Unrealistically?) prides himself on safety
My suggestion above was/is truly stupid!

Thank You , funola.

leathermang · #23 09-09-2016, 12:07 PM

Quote:

Originally Posted by compress ignite

'Tis a wonder I'm not living in a Burn ward.

For someone who (Unrealistically?) prides himself on safety
My suggestion above was/is truly stupid!

Thank You , funola.

Ok.. I can not tell if you are being facetious in your reply to Funola or being serious...

but in case others also have trouble ' reading ' the situation..

FUNOLA is CORRECT to warn against sucking anything volatile into a shop vacuum . We do not want any forum members hurt by anything like this.
Shop vacs seldom have ' explosion proof ' motors and the motor is down in the air space which is shared by the incoming trash and fumes...

Demothen · #24 09-09-2016, 12:35 PM

The flush I used is pretty heavily pressurized, so it will blow most of the junk out of the system on its own. Follow that up with lots of compressed air (i think my nozzle was rated to 90 PSI and I stepped it up from ~20 PSI in 3 or 4 steps to get most of the fluid out without making a huge mess). It also did not harm any paint it touched, actually it helped clean the engine bay if there were any spills. I really cant imagine how 90 PSI against junk caught in a fluid would not be adequate. I think I mostly used an old gatorade bottle with some paper towels in it to catch the flush, frequently pouring it into a larger container. This was following the instructions of the flush and seemed to work quite well (I dont think it specified to step up the pressure, but that seemed like common sense) I did use several cans of the flush in total since I didnt reuse it.
The stuff I used was Interdynamics AC flush in a pressurized can. Found it locally but it seems like a lot of places sell it.

leathermang · #25 09-09-2016, 01:10 PM

Interdynamics AC flush also available in can of liquid...
which might be easier to use for people already using a nitrogen bottle with regulator..
a can seldom allows real control over output... but with gauges on nitrogen bottle can be started at zero and ramped up..
I am thinking about the potential for being splashed in the face by some combinations... so once again... all AC work should include GOGGLES for you eyes...and maybe a full face shield over those....

Interdynamics Premium A/C Flush and Clean Auto A/C Flush Solution (32 oz.) CQS-11: Advance Auto Parts

Demothen · #26 09-09-2016, 01:31 PM

Oh, No. I controlled the pressure of the air i used after injecting the flush, not the actual flush. It flows fairly quickly though.
Yeah safety goggles are a must. Also good airflow in the shop is a good idea, and a respirator.

funola · #27 09-09-2016, 02:40 PM

Here's a thread on AC flush Stor bought reccomended ac flush solvent? - Automotive Air Conditioning Information Forum

They didn't have anything good to say about Interdynamics.

Demothen · #28 09-09-2016, 02:47 PM

Hmm, that thread's 8 years old, so the formula may have changed. It does seem to be oil derived and doesn't evaporate quickly, which is why I used so much compressed air - but I didn't see any signs of it being trapped in the lines or anything. It definitely flushed the old oil out pretty well, as well as at least 2 clogs. I also left the system open to atmosphere for a few days before I pressurized it with nitrogen then vacuumed it out. The supplier of my AC parts suggested an overnight soak in mineral spirits to clean the metal hose ends that I'm reusing, which seemed to work well. I won't be flushing the system again this time since everything will be new except for those two fittings (reusing the two connections at the evaporator only, 100% new system for everything else)

funola · #29 09-09-2016, 02:48 PM

Another thread on pitfalls of AC flush removing flush from evaporator - Automotive Air Conditioning Information Forum

leathermang · #30 09-09-2016, 03:00 PM

[QUOTE=funola;3634787]Another thread on pitfalls of AC flush removing flush from evaporator - Automotive Air Conditioning Information Forum[/QUOTE

Seems like that was about bad or incomplete procedure..
as compared to liquid flushes being bad...
bad procedure on anything is bad procedure...