a/c high side line w/muffler no flush?

[f-64]

I have been looking for the answer to this question for some time now. I have heard that you should not flush an a/c line with a muffler or a filter in it. My question is why not? I am the kind of person that needs to know the logic of something before I can accept it in practice.

Anybody know the reason?
Thanks, Bob

 

[Glacier991]

The reason you do not flush a line with a filter is that the entire idea of lfushing is go get contaminants OUT, not trapped in a filter... and if there's a filter and you needed to flush the system, it ought to be replaced anyway... so remove it, flush, and then reinstall a new one. As for mufflers, for the most part they are nothing but an empty can with offset intake and outlet barbs. IF you are removing it from the vehicle to flush, and can invert it to get all the flush out, great. If not, you will leave a lot of flush IN the can (some even have baffles which can retain even more if left horizontal..) Me ? I'll flush 'em, but I remove them first.... and hold then vertical a while until I have gotten the flush out. Others may have other reasons, those are mine.

Happy Exploring

Chris

 

[f-64]

Chris, Thanks for sorting out that question. I do have a muffler and the line is removable which I did and flushed it then hung it up to dirp dry. finally I shot some air through it to finish it off.

Here is the reason I am asking. Last Fri. I tore the system down and did a complete flush. I hung a rebuilt compressor from Auto Zone on along with a new accum/dryer and also a new o tube and pulled vacuum for 3 hours.

I did not find much discoloration at all in the o tube but there were a few small particals.

Anyway Once I charged it with two cans 134a I was getting 45deg air at the center vent. The best that I have ever had in this car. However with in 15 min. the high side pressure was 350+ and my cold air was gone. I did not run it any more and today I did the hole thing over.

This time the o tub was totaly gooked up with really black curd, thus the high pressure.

I flushed everything again and shot air thorugh the compressor used the same accum. it was the second one I bought in as many days. cleaned the o tube, put it all back together and pulled vacuum. Crossed fingers and gave it another try since I did not have anything to lose at this point.

I now have vent temp of 55deg which is still not good but better. The high side is 325. low is 35-40. outside air is 112. This is at 1500rpm.

Why did the new comp shoot that crud. and is my only answer to repalce it again?

Thanks for your help, Bob

 

[Glacier991]

If I have a black death on a Ford FS-10 or FX-15 (maybe I have those backwards I think of them in the same breath) compressor, I do a firewall forward replace. I have found it's impossible to do a reliable flush on that kind of failure. I'd probably replace the evap if it was easier to get to, but it is "somewhat protected by the Orifice valve. You didn't mention you had a previous failure. I'd probably have told you, in keeping with my firewall forward beliefs... to have dumped the muffler (which in these cars is integral to the return line) in that case.

I too am curious why the compressor threw up.

Keep us posted on the progress.


Happy Exploring

Chris

 

[f-64]

Chris. Here is one of those odd ones that you just scratch your head at and say hmmmm.

The next day after I posted my last reply I started the car that morning and it was 89deg outside and I was getting 35deg air inside at the vents. So I aborted my trip to Auto Zone and just let it ride for the day. Later in the day when it was 108 outside I was still getting 40deg air at the vents. So with pressures looking good at h-220 and L-25 I think will just leave well enough alone untill it blows up again.

When it is around 110deg outside it just takes longer to drop the vent temp down to 40deg. This is, I figure
because of the high cubic volume of air space in the Explorer and with out a rear air it is alomst asking to much of that wimpy will dash air unit.

I got this idea to take some left over clear sheet vinyl and streach a rod from one clothes hook to the one on the other side at the back seat door then drape the vinyl over the rod. There by effectively closing off the rear area form the rest of the car and now I don't have to cool so much space all at one time.

What are your thoughts, Bob

 

[Glacier991]

Your climate really tests an AC! In high temp situations you sort of get a double whammy effect. Hot air in the car to start puts a load on the evaporator, and as a result cool gas does not make it back to the compressor (which actually helps cool it) The compressor gets warm, causing higher head temps. It is already hot out, and the airflow over the condesnor is thus hotter than normal so less superheat is removed at the condensor and the head pressure goes even higher. pretty soon the compressor is working to pump into a really high head pressure, and doesn't fare as well as with lower temps. All in all it's a stacked deck against the system.

Try this sometime. When you have a high head pressure high ambient heat situation, spray the condensor with a hose and watch what happens to the pressures. I'll bet if you do that for a few minutes you may find you can stabilize the system at a lower pressure and lower your vent temps. All in all your system sounds like it's doing a great job - and probably thinks you took it to hell and are trying to cool the whole damn place. <g>

Cool Exploring

Chris

 

[f-64]

You know you may be right because I think I herad my a/c saying Colorado, Colorado, Colorado. --------- It must be time for a long trip to Colorado. Ha ha.

Anyway If I read you right and the water spray does drop the system stress then a bigger or better condenser should help.

If that is an option I am not sure that I can find the space for a bigger one.

Bob

 

[Glacier991]

A bigger and better condensor (or more airflow across it, or both) would definitely help ANY car on a HOT day....as would a trip to Colorado <g>.

Cool Exploring

Chris