I have a 95 jimmy that I changed rad fluid in last summer. I have bubbles in it so reading some threads here sounds like I have to burp it out. My question is, I have hot air coming in the cabin, but the air flow doesn't seem to be there. Is there some way of cleaning the heater cores' outside without having to take the whole thing apart?
Thanks in advanced.

 

search youtube

 

air flow doesnt seem to be there.
does the fan soud like it is operating properly on the correct fan speeds

and when you select different vents is it changing properly and is it only blowing out of those vents.(if not could be a vacuum leak)

 

I replaced the fan last winter (new). All 4 speeds work properly. It just feels like it's not going through. When I select where I want the air to go it does change to the selection. Is there a common problem for a vacuum leak on this truck? I was just wondering in the spring if I should dump a small container of diluted laundry soap mixed with water down the air intake, then rinse it? Thanks again.

 

on my 2000 i know the vent selector is vacuum actuated, on my 88 it was cable. i think the 95 should be vacuum as well. I had a vacuum leak on it once that prevented me from changing the vents. so if you cant change vents this is a problem.
You thought it was a heater core being a bit dusty/plugged, not very often this would happen, easy way to test this is see how much the air blows out of a vent when you have it set to heat, and then switch it to cold and see if it blows harder or the same.

I have not heard anything about dumping water down the air intake, i cant imagine it would hurt anything because there should be no electronics in there and should drain from the ac drain hole, but i dont think that would solve that problem if you have a big plug.

 

Yes the 95 is vacuum actuated. I will test it from hot to cold and let you know. Thanks for your input. Also how much of an incline does the truck have to be in to burp the heater core of air bubbles. Like I said above I have hot air but once in a while I could hear bubbles going through. I have a bit of an incline on my driveway....would that be enough?

 

Even on a '95, I believe the mode door (aka temperature door) actuator is electronic and not vacuum actuated.

There are a few threads on that subject relating to the 98+ trucks specifically that might help in your case. On the newer trucks, it is located on top of the HVAC housing accessible with tiny hands by dropping the glove box down and out of the way.

 

Well I did the full hot to full cold and lots of air in the full cold but as I turn the **** to full hot the air flow slow down dramatically. Semi blocked heater core or what?

 

sounds like leaves or something is blocking the flow. if you have a local harbor freight in your area they sell a borescope for around $100 you could stick that down your vents and see whats going on without pulling your dash apart.....

http://www.harborfreight.com/digital...era-67979.html

 

^ agree, def sounds like something is blocking when you switch to heat......
spending the cash on the scope is easier than pulling the dash out to get at the heater core.......but.......if you use the scope to see that something is blocking it then you will probably have to pull the dash out to get at it anyways.......i think shops quote heater core replacement at 6-8 hours labour, so that puts it into perspective on how much work it is to get at it (And how expensive it could be to get a shop to do it).