Well, I'm baaaak! An AC (very knowledgeable) snowbird friend of mine had a look at the truck. This guy is a young 84, was previously in the AC business, and knows AC concepts in and out. After checking pressures and poking around at everything, his opinion is that there is nothing wrong with the compressor and more than likely it is the expansion valve being stuck, orifice plugged, or whatever type control is used in my 02 F150 5.4. So, can anyone tell me specifically where my expansion valve/control valve/orifice is located? We weren't able to locate it under the hood. I would really feel bad if I replaced the compressor to only find out it was something else.
Thanks, Sho, and others who contributed.
Deke
NE MI
Frost this morning

 

Sorry your friend is wrong. The pressures being near equal is a bad compressor. A clogged orifice tube (its what's in your truck) would cause the low side pressure to be say 10psi and high side at 300psi. If the compressor is running and fully charged, and the pressure are almost equal then you have a bad compressor. Now when you remove the compressor I would change out the orifice tube and drier at the same time. You also need to flush the system if the Compressor puked its guts into the lines which would destroy a new compressor.

 

OK, thank you. I'm convinced (but not happy) and resigned to get this job done somehow. Thanks for the response. Now, where do I find that orifice tube? Is this something I need to tear the dash apart to find?
Thanks, again.
Deke
NE Michigan

 

its in the condenser to evaporator line. Condensor is whats infront of the radiator, evaporator is whats inside the truck.

 

Thanks, Irons. I really appreciate all your help. I hope I don't sound dense. I'm just trying to eliminate all the inexpensive possibilities before I tackle this thing and go to the big stuff. I think I have found where the orifice tube is. Best I can find out is that it is at the engine side of the firewall where the condenser tube feeds to the evaporator. To separate the tube I think I need a special tool called a "spring lock release", but not sure what size. It is definitely a tough spot to reach, but doesn't appear impossible. Possibly the nearest auto parts place will have a set.
I did another gauge check today and sure doesn't appear that the compressor is doing much compressing. The readings were:

static
Hi - 73
Lo - 73

Running with max AC
Hi - 78
Lo - 78

Persistent in Mikado MI
Deke

 

Yea compressor is junk. They sell kits with like 5 different sizes. Its probably a half inch or 3/8 one I don't remember off the top of my head. Leaning towards half inch

 

Just get the set that has 6 or 8 different sizes. The set runs around 10-20 bucks.

Those readings indicate the compressor isn't running at all.

A "weak" compressor will have insufficient pressure differential between the suction and discharge. Someone who has reported been in the A/C business long enough to be "very knowledgeable" should have known how to interpret such readings.

I just had to replace the compressor on my V10 a few weeks ago (a warrantied unit less than 2 years old was leaking at the mid-body gasket). I went in through the wheel well (after removing the fender liner) and it was a lot easier than going in from the top or the bottom to get the manifold attached.

 

Hey Fox, sounds like you are making progress. I posted earlier in your thread about my a/c clutch failing on me last year. Well, my compressor was starting to get pretty darn noisy when it kicked in, and I decided to just go ahead and replace the thing (along with the accumulator/drier and orifice tube) before it crapped out and really messed things up. I did the accumulator this afternoon and was happy to see that the lines were nice and clean. Planning on the orifice tube and compressor tomorrow.

BTW, I have the 2002 service manual on DVD here. Lots of good info, but one thing I noticed repeated throughout the a/c section is this (FWIW):

NOTE: Installation of a new suction accumulator is not required when repairing the air conditioning system except when there is physical evidence of system contamination from a failed A/C compressor or damage to the suction accumulator.

Anyway, I can't remember where in the heck I downloaded this service manual but I could rip it as an iso and host it you don't have a copy...

 

BTW, I was able to remove the accumulator fitting at the firewall using just the Plastic indicator ring shown in the following diagram. As long as there isn't tension on the coupling and the coupling spring is loose, the indicator ring can be pressed back in to the cage and it will keep the spring from engaging on the flared end of the female fitting. I'm hoping the condenser to evaporator line works the same way.

 

If you want a warranty on a replacement compressor, you usually have to have proof that you also replaced the accumulator and o-tube (sometimes, have to prove the system was flushed).

If the compressor warranty is important to you, check the terms from your parts seller.

 

Good point on the warranty.

Deke, I just pulled my condenser to evaporator line. On my system the orifice is located at the condenser coupling, not at the evaporator spring lock connection at the firewall. Wish I would have known that, I wouldn't have removed the whole line.

 

Bingo. If we have a compressor fail we have to do the whole kit for a warranty. Sometimes (we use napa for parts) they will allow me to just replace a compressor if say just the front seal leaks or clutch is no good. Not to often do they bite on that one.