Automotive Air Conditioning Information Forum

I have a 2007 Lincoln Town Car. Uses a fixed orifice with accumulator system.

Last year I bought the car and the Evaporator and compressor drive seal was leaking, so I replaced with new: evaporator, fixed OT, low-line from evaporator to accumulator, accumulator, compressor, oil and refrigerant (without stop leak).

Now, a year later, it just doesn't work if ambient temps are above 77º. High side pressure doesn't get very high (about 160) and low side doesn't get very low (about 90). I added a little refrigerant to see if it had leaked, but both sides went up evenly. I couldn't get the pressures to separate, meaning low side low and high side high.

What I figure is that the condenser was trashed with stop-leak by the previous idiot and the compressor I bought was from Vato-zone, so it probably just killed itself anyway, crappy reed valves who knows.

My plan now is to just replace everything else and start new to see if that gets it working again, but I hope I only have to do this ONCE.

So, what should I replace, what should I flush, what would you do?

I am thinking I will replace, with all OEM equipment: Compressor, high-side line with muffler, condenser, OT, accumulator.

That means I will be reusing and/or cleaning: low line from evaporator to accumulator (purchased last year), low line from accumulator to compressor, high line from condenser to OT/evaporator, evaporator (purchased last year).

What are the odds that the evaporator has junk in it too?

Open to your advice!

That is a CCOT system, so the O/T should have stopped any trash before it got to the evaporator.

If the compressor was shedding debris the condenser is the primary filter. I would contact Tim at AC Kits for replacement compressor & condenser - the condenser on that car is also the trans cooler.

Your "new" lines are straight with no mufflers, so you can flush them out with solvent. Mineral spirits, Stoddard solvent, etc will do the trick, just blow air through them until you can't smell solvent. Obviously "odorless" solvent is not what you want...

I would start with the O/T, see what it looks like. The really bad sealers will harden up on the screen like dirt clods. If it is just full of metal & black stuff you are just chasing a couple of failed compressors - and seeing what made it past the parallel flow condenser.

You are definitely on the right track.

Considering I replaced the evaporator when I replaced the OT, then your opinion gives me enough confidence that if the OT screen is intact, I won't be worried in the least about the condition of my evap passages.

Since all of the other hoses (minus the one with the muffler, as that is being replaced) were present whenever the last compressor(s) failed, are they still able to be cleaned to an acceptable level?

Can somebody post a picture of what flushing a hose would look like? I guess this is something I can do myself.

So replace high-side hose with muffler, then flush the other three hoses, replace all components with OEM parts except the evap. and I should be golden?

Any tips for removing a really stubborn OT? When I replaced the old one the sumb**** was well lodged in there. The end that the tool grabs onto snapped off and I just threw the evaporator out as it was.

Bump. All of the parts I mentioned are in.

Can anybody answer my last post before I get started, I want to get this right the first time.

Flushing a hose is simple with it removed. Pour some mineral spirits in it holding it in a "U" so it stays put. Hold a thumb over each end & shake violently. Dump the solvent in to a clean container & inspect the solvent for debris. Repeat if necessary. Blow dry air through it until you can't smell solvent with the end of the hose close to your nose.

Stuck orifice tubes are easy to remove with a long drywall screw.

Alright, that gives me a lot of confidence to start. I'll let everybody know how it goes.

Thanks!!

OK now I'm **** beyond reason.

So I did everything exactly as described.

Compressor came loaded.

Pulled vacuum and let it stand for an hour.

Then I started the car and whenever I opened the low side to fill it, the pressures jumped on the low gauge and slowly climbed on the high gauge. At some point the clutch started cycling and the high side only ever got as high as 125psi.

The low side is stuck extremely high!!!!!!

I've shut it off and watched and it reads about 120 on the low side and 90 on the high side with everything shut down.

The pressure won't budge! WTF!?

Your low side connector is not depressing the Schrader valve.

Schraders act like check valves if they are not depressed - you can push some refrigerant past them, but never get an actual reading of system pressure.

With the system cycling - Grip the low side connecter firmly, pull the release ring back & PUSH it on a little more. Then release the ring & ease up on the connector so it stays installed. Now check the gauge.

Sometimes a zip tie around the connector & line will push it on enough to fix things. Some connectors have an adjustable depressor pin that can be used to fix whatever is out of tolerance.

This is usually a problem with inexpensive couplers, but can also be an out of spec fitting on the system.

This website is unbelievable. You're exactly right. I bled the hose down a little without letting any air in, then reinstalled the low side valve and opened it. Once I rotated the fitting a little the reading matched the high side exactly and when I turn it on it works.

I was ready to abort all due to cheap neglected gauges. I even had to take the dial cover off and adjust the high-side back to zero because it's likely been dropped so many times. Oye vey.

Bohica, thanks for spoon-feeding all of the answers I needed.

I went with ALL OEM parts. The compressor was loaded, labeled with the specified amount, and I confirmed it just by looking inside the ports.

It was blowing cold with one can, then by the second can I was freezing. My phone got a cloud of condensation on it from sitting inside the car.

To get every last drop out of the cans (calls for 23oz, so 2 cans minus losses evens out) I kept it in a HOT pot of water near the end, sprayed the condenser periodically with a mister to drop the high side pressures thus dropping the low side pressure and sucking more out of the can. I kept the valve open until the pressure of the refrigerant line was equal to the lowest low pressure line reading. There was barely a whisper when I pulled the can off.

I have never felt one of these cars blow so bone-shriveling cold.

I really hope this lasts. I can't afford to do this again probably ever but I hope I've done everything right. The ONLY thing that wasn't flushed was the evap and that leaves me worried. The OT was clogged almost completely on the inlet side with metal...

Thanks again for taking time to help me get this knocked out!