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gt350ed · 06-09-2015, 03:36 PM

Mine is a 90 1/2 Bounder, GM Chassis with 454. The entire rig, engine, etc. is in excellent condition, 37,000 original miles, always garaged, original owner.

My in-dash A/C has not worked for some time, but since we have not been using the rig, and I have not made it a priority, I had not looked into it. Now, I'm making it a priority. I always thought the issue was lack of freon EXCEPT for the fact that lack of cold air was fairly immediate, and the entire rig has such low mileage.

For starters, I'm noticing that the compressor clutch is not engaging. I know this can mean a few things, including low or no freon. But, I am wondering if it might be a fuse or relay. Although there is a fuse holder/ box under the flip-up gauge panel, I'm not finding the typical plastic power center type box with relays. And, of course there are the myriad inline fuses for the nightmarish random wires and harnesses also below the flip-up panel, but so far, nothing found.

Any ideas as to where I might find the AC relay or low pressure switch if there is one?

BFlinn181 · 06-09-2015, 05:42 PM

Often chassis fuses are under the hood, on the firewall in a plastic box holding fuses and relays. I would start with hooking up a manifold gauge and check the pressure of the coolant. (Freon is a © by Dupont) The low pressure switch is usually right next to the expansion valve and dryer, it has 2 wires attached usually.

gt350ed · 06-09-2015, 06:21 PM

Thanks. The box, if one exists on my Bounder, does not appear to be under the "hood". Due to its age, there may not be any box. That's why I'm hoping to hear from someone familiar with my vintage Bounder. As for "freon", although I'm well aware that freon is a DuPont copyrighted product, the fact is that if you ask folks what that cold stuff is that you put in A/C systems, 9 out of 10 would say "freon". I was appealing to those 9.

BFlinn181 · 06-09-2015, 06:38 PM

If I had referred back to you using the term freon, I, more than likely, would have been corrected by some nitpicker. I'm not worried about Dupont police or lawyers, call it what you want. It's most likely R134a, there should be a sticker near the radiator. Here's a link to your Bounder's owner's manual, unfortunately it refers questions like yours to the chassis manufacturer.

http://fleetwoodrv.com/partsandservi...90_BOUNDER.pdf

gt350ed · 06-09-2015, 07:58 PM

Quote:

Originally Posted by BFlinn181

If I had referred back to you using the term freon, I, more than likely, would have been corrected by some nitpicker. I'm not worried about Dupont police or lawyers, call it what you want. It's most likely R134a, there should be a sticker near the radiator. Here's a link to your Bounder's owner's manual, unfortunately it refers questions like yours to the chassis manufacturer.

http://fleetwoodrv.com/partsandservi...90_BOUNDER.pdf

It's R12. No sticker. And, by the way, it may very well BE Freon, but I digress.
Since I'm the original owner, I have the owner's manual, but thanks. Ya, the owner's manual is of no help, nor is GM. I've tried.

ANY VINTAGE BOUNDER OWNERS OUT THERE?

muskamoot · 06-10-2015, 08:50 AM

You probably would want to convert your system to R134a from R12 to begin with.There are several kits available.You will also probably be looking for a leak in your system,so some dye will probably be helpful if you are intending to do the repairs yourself.There are plenty of DIY videos on youtube that will be helpful and there are also always "experts" that will nit pick your efforts.Bottom line is that fixing your leak and refilling your system should result in cold air.

gt350ed · 06-10-2015, 09:20 AM

REPEATING my question...

"Any ideas as to where I might find the AC relay or low pressure switch if there is one" ON A 1990 BOUNDER?

TQ60 · 06-10-2015, 07:53 PM

Only guessing...

Follow the lines from compressor toward cabin and look for anything with wires on it.

Also look for the dryer which is about size of spray paint can.

The low pressure switches are sometimes located there.

The switch will be on the low side of tge compressor or the larger of the 2 hoses.

Get a manifold and just check pressure to save some time.

That year is likely r12 and likely low.

Back in the day r12 was $0.49 a can and standards very poor so it was common to toss in a can every year.

New factory r134 systems require a lot less service than the old r12 ones.

Converting to r134 will require every hose to be changed as the molecules of r134 are smaller and can go through the old r12 hoses.

Hot shot is a direct replacement for r12 (suggested by local industrial shop) and works well in ours and not too difficult to get.

If you have other vehicles then get the 35 pound jug and you will be good for years...