Anybody know if the ac evaporator on an 86 f250 can be gotten to from under the hood so it can be cleaned/blown out. I think it might be pretty dirty.

Reason I say this is because my ac system checks out fine. Good cooling etc...except I noticed when using max ac the blower has slowly decreased the amount or volume of air. It used to blow like gangbusters, but now about the same as regular ac.

Could it be something else? When I switch to heater mode the fan blows real hard again, so I don't think it's the fan. Besides I replaced the blower motor and resistor about 6 months ago.

Thanks for the help and ideas...

BeerCan500

 

Yes you can.
Remove the blower motor assembly and you can see the evap(partially)
You can try vacuuming with a shop vac(vacuum cleaner) .
If it is real dirty. You can take the housing apart like you were going to replace the evap.
A few screws hold it together.
One bolt goes through the firewall..It is next to your engine on the lower side...Accessible from inside of cab..
To do a really good cleaning, I would remove the cover.
Whichever way you go, You are going to realize a big differnce in volume of air.
Whatever type of cleaner you use is your choice. There are MANY good cleaners out there...Keep in mind the evap is aluminum.

Hope this helps..Trav...

 

Take a look at the vacuum-powered stuff that operate the various doors in the ductwork and make sure everything is correct & functional, it's not unheard of for the hinge pins on the doors to break.

 

Thanks guys...I think the vacuum and stuff is working. At least everything does what it is supposed to do when you change to all the settings and back...But that don't mean the blend door is opening and closing all thr waybI guess. I thought if the blend door was sticking somewhere my temps between ac and max ac would change, but both are down to a steady 48 degrees. Just don't get that "extra" air on max...

 

An easy door to check is the one near the pass side hood hinge. That little actuator should move when you go from max to normal cooling.

 

Yeah Franklin2, I checked that...It moves what looks and feels like a full throw when switching back and forth between max and normal...Boy, as much as I hate to I guess I might have to tear into it...I'm afraid it will only get worse...

I have a 12" X 12" X 1/8" piece of flat ABS Black Plastic. I wonder if there is enough room between the evap and housing if I carefully cut an (I don't know...maybe an 6" square out of it) from under the hood to get a real good look and cleaning. Then make a 1/16" gasket and cover the hole with my black abs to seal her back up. What do you think?

Thanks for more of your thoughts...

BeerCan500

 

I would not go to that trouble. Just take it apart if you want to get to it. You can reach in somewhat from the fan motor like someone else suggested also.

Tearing it apart and putting it back together will take the better part of a Saturday.

 

But it's a 30 minute job to remove the housing and then you can clean the entire thing. Am I missing something? Is there something blocking you from just removing the side of the evap housing?

 

No your not missing anything...I'm just not that experienced with opening up the evap box. At first it looked like a weeks job for me and was looking for an easy out.

Franklin2 is right...may as well just get after it and do it as right as I can. After doing some more research and poking around some more I think I can git-r-done without to much of a problem... Even it it don't help much, the evap surely needs a cleaning anyway. If it works, I won't have to go any further unless I see something that needs attention...

Thanks guys...

BeerCan500

 

I cleaned the one on my 80. Besides cleaning the coil, you can also get to the hole that goes into the firewall under the windshield, and dig all the pencils, watches, and all kinds of junk that fell into the defrost vents over the years. When I was done, it made a big difference. These trucks have very good heating systems when everything is working as it should.

 

I agree on the heating...Mine has always produced great air volume and enough heat to bake a potato on the defrost vents...So much heat I usually have to keep her down on low and fan on low...Those setting give me plenty of heat...As for the A/C...the same...Of course mine is still working on R-12...I know I will probably have to convert someday, but so far I have been able to keep her running on the R-12.

Anyway...I got to the evap...boy oh boy...she was almost completely clogged up with this brownish looking gunk, hairs, fibers, a button, fuzz, and clumped up dirt in the evap housing...Maybe I'll get some air bowing thru there again...

 

You'll probably think Issac has entered your cab.
It will be more air for sure.
Glad you got to it ok.
You're probably gonna need that AC a little while longer in Cowtown...Trav..

 

If I was back in Morrow (martown) Ar. I probably wouldn't even need an ac. I was so far back in the woods we didn't git no mail and there were plenty of creeks and the river to swim in...LOL

 

I know what you mean.
It has been humid and hot here.

Still need the AC during the day.

I can relate to your heat, I lived between Lake Worth and Azle from 73 to 76. Nothing like Jacksboro Hwy...LOL...Trav..