Lincoln Town Car - Complete replacement, how to clean?

[bohica2xo]

Evaporators are protected with the O/T screens. Whatever makes it past that gets stuck in the accumulator - the "J" tube & dessicant stops junk very well.

The big pieces spoil the condenser. What makes it through that is stuck on the O/T primary screen.

Hard to say what failed on your first repair. You are back to new with all of the underhood, so you should be good to go.

[aarondale]

The PO tried to repair a leaky evap core with stop leak and then...no wait that's all I think I need to say.

I pulled the core and replaced it and several other parts. Combine contaminated system with Autozone compressor and here we are!

Not as cold as the fancy new electric-compressors with variable displacement etc but MAN it's the coldest Town Car I've ever driven.

[aarondale]

I do have some final questions.

Whenever I put the new compressor on last year, the fan had quit cycling and the output went up to the end of the gauge, probably over 450psi. Would this have doomed the old compressor, driving like that for a day before realizing the engine was straining to turn the compressor? Shouldn't it have cut off after a certain pressure, due to the pressure switch?

Second, why is it cooler whenever I slow down?

The fan is a variable speed, single fan. As far as I'm told it turns off at 50mph and over. Whenever I turn the car on and get on my way, everything is chilly and crisp. Once I'm on the highway over 60 or so, I feel the performance fall off as it starts to feel a little stuffy/humid.

Texas weather is hell. It's 92º with humidity 50% or more. I wouldn't think a luxury car should have this issue. I don't have any such issue on my similar Grand Marquis.

[aarondale]

Welp, things are screwed up again.

Slowly I've lost that crisp coolness.

At idle, my suction side gets to about 30PSI and the high side stays around 275PSI at 90ºf, windows up, recirc, with a cooling fan helping the condenser. If I rev to about 1,400 RPM the high side gets to 450PSI and low side maybe around 25PSI.

Did I completely **censored** myself by not flushing he evaporator???? It's the only part of the system that wasn't cleaned or replaced.

My OT came out looking almost like the black death. Just metal compacted all over the screen, but the screen wasn't broken and there was very little on the evaporator side, after the orifice.

At this point, can the dealer flush my evaporator, replace my OT and then just charge and carry on?

[bohica2xo]

450 psi - looks like your fan quit working or you have a condenser blocked with debris.

Even the idle test is showing high head pressures for 90f. You have a condensing problem. Airflow is the place to start looking.

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[aarondale]

So revving the engine shouldn't cause an increase? Or how much increase is acceptable?

I'm not convinced it's airflow. It's a new condenser, and when I pulled everything out I very thoroughly blasted the radiator clean with degreaser and high pressure water until I could see clearly through it and the was clear.

The fan is a year old and still blowing very strong. I have even hosed the condenser down when running and it only drops about 20-30 PSI of the high side.

Are you suggesting it's plugged up inside the channels???

[bohica2xo]

Where is the high side port located?

If it is between the compressor discharge & the condenser inlet, there is a chance that the problem is either the condenser OR something downstream.

If the test port is AFTER the condenser discharge, the problem is downstream of the condenser.

450 PSI is usually a condenser issue. I know that is not what you want to hear.

[aarondale]

The high-side port is on the hose between compressor and condenser. It's only 450 whenever I rev the engine. At idle it's 30PSI and 275PSI. Drops just around 250 if I hose it down.

My problem is this:

A. How can I test to be CERTAIN where EXACTLY the problem lies? I'm taking it to Ford tomorrow and don't want to have to throw THAT MUCH more at it. Is there a "wrong way" of installing an orifice tube that would cause a blockage? (Of course I installed it using the tabs, so it's at least pointing the right direction)

B. How could it have clogged if the hoses were thoroughly flushed and all components are new and were only exposed to atmosphere for a VERY short time while assembling?

C. Is my compressor doomed from driving like this for so long now??

The OT was completely covered in metal but the screen was not broken. The inlet side was crushed and caked, the outlet side only had a few minor specks of debris. The ONLY component in the whole system that was present whenever the last compressor failed is the evaporator. Could the evaporator have been clogged with debris from the previous failure?

ALSO, what would be the symptoms of too much oil?? The compressor came loaded, but I didn't account for any oil that may have remained in the evaporator.

Yeah, I'm panicking. Getting hit in the head with a brick is better than burning four-weeks' pay.

[bohica2xo]

Your compressor is good - it pushes 450 psi. If you don't ask it to continue at that pressure all summer it will be fine.

You have replaced the system one part at a time, so it is frustrating, We have all been there a time or two.

Your first run at the repair included a new evaporator & O/T, so that is still clean - and was not the source of any further contamination.

You replaced the compressor & condenser on the second repair, and serviced the O/T at the same time.

It cooled very well from June 26 to July 5. If it had too much oil on board it would never have cooled well

Now it is not cooling & has high head pressure.

This all points to a condenser problem. The external issues are airflow - dead fan, plastic bag in the space between radiator & condenser etc. Check all of that first.

Internal issues can be checked from the outside by feeling the condenser face for hot or cold spots. A restriction can act like an expansion device. Check the condenser discharge line connection - it should be cooler than the compressor discharge connection. If they are close to the same temperature the condenser is not transferring heat.

If you can't find anything wrong externally, recover the system & pull the O/T for inspection.

You said that you used "OEM" parts. Where did the condenser come from? Motorcraft part?

A couple of years ago I bought a cheap replacement condenser on e-bay to use for a mockup. No way I would use a $30 condenser. On a lark, we hooked it up for a flow test, & blew some 350 psi nitrogen through it. Seemed like it flowed respectable numbers. A friend told me he wanted one for an aftercooler for his air compressor. After I was done with it, I handed it to him. Tipping it around in the office he asked me how many BB's I put in it? Yep. After blasting it with nitrogen & handling it a lot all of the manufacturing debris broke loose in it. It was a big, flat maraca.

Moral to the story is you may just have a defective condenser - even OEM suppliers make one occasionally. I know that Lincoln added to the pain by making the condenser the transmission cooler as well, so it is less fun to change than most.

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[aarondale]

Ok I'll have Ford go at it with their diagnostics tree and a laser thermometer.

All parts were in Motorcraft boxes, including the condenser. All from different eBay vendors; all in the US and all with good ratings.

Damn.