Can the a/c condenser be flushed in place on '87 300SDL? - Page 3 - PeachParts Mercedes-Benz Forum

Demothen · #31 09-09-2016, 03:01 PM

Both of those threads are very interesting Funola, I wish I had read them before I tried flushing my system.

I really doubt that my evaporator flush worked as well as it should have, though I think the condenser worked pretty well. The evaporator, as you know, is actually a parallel flow system, though it's parallel in 5 circuits only. I have my old evaporator still, once I have the new system finished I plan to pressure test the old one under water since I suspect strongly that it leaked. If it passes that I may try to offer it to someone who needs it, otherwise I might cut the ends off of it to see if all 5 circuits are actually clear of debris & clogs before I send it to the scrapyard.

I think your solution might be one of the better ones for the DIY'er, since I cant imagine it cost much for the pump, fittings, and solvent you used. If i had to do it all again, I would probably try your technique, although the local junkyards are low on MB's right now, so I'm not sure if I could scavenge enough lines to do the job.

funola · #32 09-09-2016, 03:14 PM

Those self propelled power flush in a can can't do a good job unless you use many of them. That gets expensive at $17 a pop. I think it is necessary to run the flush through many times through a filter in order to do a good job. The solenoid pump cost $8 to 9 on Ebay. If I have to flush again, I'd use vacuum instead of the pump, which will be even neater than using a pump.

Scavenging lines and fittings is necessary only if you want to pressure test at high psi. For flushing with a pump, use clear PVC tubings and neck them down with clamps. Just keep the pressures below 20 psi and they will not blow.

Edit: all the fittings can be bought if you don't want to scavenge. You'll have to download a few AC bead lock fittings catalog and learn the system in order to know what to order.

Demothen · #33 09-09-2016, 03:19 PM

I used four cans total on my system since I had some nasty clogs. I could have probably gotten away with 2 if I had let it sit in the evaporator and condenser longer. I'm not sure how much velocity you'd get from a vacuum - I mean, the max you can get is really 15PSI, where I can blow compressed air through at 90PSI or more. There's nothing stopping you from reusing the flush in a can, I didn't because I wasn't planning ahead real well.

funola · #34 09-09-2016, 03:24 PM

I've collected lots of WVO with a sucker tank. The initial suck is pretty violent. Once the condenser is full from suction, let it sit to dissolve the stuff, then blow out into a filter/ container to reclaim and repeat. The filter allows you to see what's coming out, and the fluid should get cleaner with each pass.

compress ignite · #35 09-10-2016, 03:51 PM

LM,

I am/was serious in thanking funola.

'tis a miracle I survived my own stupidity.

leathermang · #36 09-10-2016, 07:12 PM

Quote:

Originally Posted by compress ignite

LM,

I am/was serious in thanking funola.

'tis a miracle I survived my own stupidity.

Or at least was not burned... or set the garage on fire....
There ARE vacuums with explosion proof motors in them ... but they cost like $2000 and up... so most people need to heed his and ( now ) your warning.

funola · #37 09-21-2016, 09:25 AM

Quote:

Originally Posted by compress ignite

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!

I tried out vacuum! Works great! Thanks for suggesting it!
Vacuum flush AC system