Low side normal /high side low stumped

[Tim]

Depends on how much you want to spend and still never be sure you will have the temp you want.

https://www.secondskinaudio.com/sound-d ... damplifier

[tbirdtbird]

We use HushMat here in the cars we install AC in.
No spray, it is self adherent. Easy to apply. Cut pieces to shape to be able to tightly cover entire roof.

Since re-heating has not been considered until just now with Bohica's post, feel both heater hoses in the engine compartment. One should be cold. If both hot, you are getting reheating inside the air box. Another way to check is to clamp off one or both heater hoses with a c-clamp or visegrips, using blocks of wood on either side of the jaws so as to not harm the hose

[bohica2xo]

Dynamat is not a great insulator, and pretty costly.

I have sprayed closed cell foam on the underside of vehicle roofs with great results. But you have to be very careful to prep the vehicle, because the overspray sticks to everything - forever.

Al alternative is mixing glass micro balloons with a coating. The transmissivity of that coating is very low for a 1mm thickness. I have never tried to spray it, or use it on an overhead surface. That would be a complete experiment. Rolled on a metal garage door inside facing south in Las Vegas it really provides a measured reduction on panel temperature.

Lots of choices depending on your skillset and how much you want to spend

[tbirdtbird]

HushMat and Dynamat are not the same

[bohica2xo]

If memory serves the Excursion Diesel has a 3 port vacuum operated heater control valve. That valve may be leaking hot water in to the heater core.

Pay attention to crimping heater hoses off - you can close off a bypass loop that needs to stay open for the rest of the cooling system. A hose coupler joining the heater hoses after you disconnect the heater core can remove all doubt.

[tbirdtbird]

I have to wonder about what Tim posted above at 6:27 meaning his last comment in that post

In my experience heater control valves leak until proven otherwise

[Excursion2001]

Wow. 5 full minutes at max load. That is hitting it hard. Good news is a pressure ratio below 3:1 even with that beat down. I am going to say the fan clutch is hanging in there as well.

I am going to say your refrigeration loop is in pretty good shape, based on pressures. A "muggy" feel, and vent temps in the 80's would indicate some reheating to me. Perhaps a blend door issue. Given that an aftermarket company like Dorman makes blend doors for the 2000 Excursion might be a reason to look there...

Also check the evaporator drain. If water is not leaving the evaporator case it can feel muggy when the car is that hot.

FYI that 5 minute run you did is like pulling the 23 foot daycruiser up the hill out of Willow Beach.

Insulating the roof could be done. It would require removing the headliner and carefully prepping the truck to spray the underside of the roof. If that is something within your mechanical abilities. I can't think of anybody doing that job commercially.

I just checked the heater hoses on both front and rear sides are cool to the touch and my heater is controlled by a vacuum valve that will let the engine coolant enter the heater core , this engine fan is rated to pull 10,000 cfm through . Iv replaced the headliner before it’s not to hard just long lol and I’m willing to do the work if it helps any and the evaporators are dry and I’m not leaking any water and it’s a really dry climate out here

[Excursion2001]

Depends on how much you want to spend and still never be sure you will have the temp you want. I mean If it helps I’ll spend the money it will just take me awhile to save up for it

https://www.secondskinaudio.com/sound-d ... damplifier

[Excursion2001]

We use HushMat here in the cars we install AC in.
No spray, it is self adherent. Easy to apply. Cut pieces to shape to be able to tightly cover entire roof.

Since re-heating has not been considered until just now with Bohica's post, feel both heater hoses in the engine compartment. One should be cold. If both hot, you are getting reheating inside the air box. Another way to check is to clamp off one or both heater hoses with a c-clamp or visegrips, using blocks of wood on either side of the jaws so as to not harm the hose

I’ll have to look into those . Heater hose is cold

[Excursion2001]

Dynamat is not a great insulator, and pretty costly.

I have sprayed closed cell foam on the underside of vehicle roofs with great results. But you have to be very careful to prep the vehicle, because the overspray sticks to everything - forever.

Al alternative is mixing glass micro balloons with a coating. The transmissivity of that coating is very low for a 1mm thickness. I have never tried to spray it, or use it on an overhead surface. That would be a complete experiment. Rolled on a metal garage door inside facing south in Las Vegas it really provides a measured reduction on panel temperature.

Lots of choices depending on your skillset and how much you want to spend

I’ll probably regret spaying it lol probably cover up something by accident lol