A/C transplant?

[pete c]

Last week the compressor on my r-12 equipped 93 mtx locked up.

The wife was driving it (surprise, surprise ) when it "started squealing and smoke came out from under the hood".

She parked it at her parents house and drove her mom's car home. I then received the familiar "that car is a POS" speech. Don't understand it. Runs fine for me. Maybe it's cause she "lugs" it. lugs- failing to open secondaries in every gear.

I went over to the outlaws house, started the car and all was quiet even with the A/C on. Ofcourse the air was no longer chilled in the least bit.

I popped the hood and found that the A/C pulley spins, but the plate on the outside of the pulley which I suspect is part of the clutch and should spin, does not. It just kinda wobbles a bit when the A/C is "on". Looks as though the battle between 220 hp of yamaha and a froze compressor was taken out on the clutch.

The A/C worked very well prior to this, although the A/C did seem to take quiet a few hp away when reved high.

Is there the slightest chance that the comp is fine and the clutch just died? I doubt it given the smoke and squeeling reported by the OL.

So, looks like it's time for me to go to the inferior but ecologically nice r-134a.

I am also the not so proud owner of an '89 slo wagon with a good r-134 conversion. It has the 3.8 drivetrain. This car still runs well but with a bit of rust, a crumpled front bumper, a cracked windshield and a leaky heater core, the old girl is starting to look more and more like what all tauri should be, a sacrificial lamb to keep our shos on the road.

Is there any chance that the slo's r-134 stuff can be used on the sho? It appears to be a quality professional retrofit, not an AZ DIYer hack job.

One more thing. Anybody out there interested in a good running 3.8 drivetrain? The prior owner had it rebuilt by a garage at around 60K. It currently has 105K. I have the paperwork. Looks like a complete engine/tranny rebuild.

It also has a decent looking set of basketweaves with good rubber.

 

[projectSHO89]

You can check the compressor to see if it has siezed or just if the clutch only has failed.

Gain access to the nut on the end of the compressor shaft (clutch side). Might be possible from the bottom, I don't know. Removal of the battery and tray will guarantee access.

The service manual calls for no more than 7 lb-ft of torque to rotate the compressor shaft throughout it's entire rotational range. The procedure also specifies that the system be discharged for this procedure.

You can get a rough idea of the health of the compressor just by using a ratchet on the nut. Any roughness or binding or exxcessive force will be noticeable.

Clutch disk, pulley, and coil (remanned) are available from AutoZone for $90.

Steve

 

[pete c]

thanks steve. I believe the system is still charged. the A/C was working when this happened. So, assuming a charged system, shouldn't I still be able to spin the compressor?

 

[projectSHO89]

Yes, however, the torque spec will not be applicable.

BTW, the 3.8 compressor and clutch will not work. Probably no transplant candidates in that 89.

Steve

 

[SHOpper]

My guess is the compressor failed. Bad news if this is true. The SHO takes a different compressor and system than a SLO, but they are not hard to get. I do my own A/C work, but parts are still expensive. If you did lose the compressor, make sure you also replace the accumulator/filter/dryer unit, and the orifice tube. Also flush the system before you put anything new into it. THe compressor could have spit lots of parts into the system that, if not flushed, will ruin the new parts. R-134a is not that bad. My 92 was retrofitted by the PO and it works great. I still would stick with R-12 if you can though. I would help you out personally, but I am out in Washington on the west coast.

- Mike

 

[pete c]

thanks guys.

so, looks like it's r-134 retrofit time. Anybody in my area (southern new england) got a wadded up gen II with a good r-134 system?

Or would it be worth my while to go ahead and repair the r-12 system? It did work well and didn't appear to leak any. I would guess that an A/C tech could suck out most of the liquid gold (r-12) so it shouldn't cost me much in new freon.

A friend of mine's bro has a garage and I believe he does A/C work. I will get his opinion.

BTW, is there anyway of having the sho's computer tell the compressor to take a break when the yamahammer is doing battle in the high rev range? I am thinking of maybe using the signal that opens the secondaries as an A/C cutout switch.

It would be rather simple, actually. Use that signal to energize a normally closed relay which would cutout the A/C.

I have been doing more than the usual 3rd gear, redline runs up the interstate on ramp lately. This is all done for safety's sake, you see. Nothing worse than merging into highway traffic at anything less than about 90mph.

 

[projectSHO89]

There is already a Wide Open Trottle AC Cutout implemented in the EEC control strategy.

Did you perform the checks I previously gave you to determine if you need a clutchonly or if the compressor has seized? A clutch is only $90 and does not require the system to be opened.

If you haven't done so yet, don't get all worked up about the conversion until you do. You might get lucky, you know..

Steve

 

[rangerj]

Pete,
Your problem could be either a siezed compressor or a siezed A/C pulley bearing. Does the pulley spin freely without "growling" or grinding?

If it turns out to be the compressor there are several sources of new or rebuilt A/C compressors for the SHO. The compressor is SHO specific to take the high RPMs. Make sure you or your mechanic get the right compressor.

Most, if not all, sellers of new or rebuilt compressors will nor warrant the compressor unless the accumulator/dryer is replaced, and the system is chemically cleaned. The oriface line is not that expensive and should also be replaced.

Replace all of the "O" rings at the connections and any rusted garter springs. It is easiest to clean the condenser out of the vehicle, and it is a good idea to have it pressure tested for leaks.

The chemical cleaning kits are available at auto parts stores, NAPA, Auto Zone, etc, and is about $50.

If you decide to convert to R-134a you can get a conversion kit with "O" rings, garter springs, high and low pressure conversion "fittings" for the guages connections, and refrigerant oil for the conversion. R-134a is just as efficient as R-12 in a system with good components.

A new or rebuilt compressor should come with a new clutch assembly. Your high and low pressure switches should be OK to reuse unless there are signs to the contrary.

The removal and installation of components is not all that difficult, and a set of tools used to expand the garter springs, in order to "uncouple" the hose connections, is about $20 at A-Z.

The vacuum pump and gauge set can be "borrowed" from A-Z for a refundable deposit. There is plenty of help here if you decide to DIY. rangerj

 

[Nook]

SAME THING HAPPENED TO ME !

SQUEEEL==== SMOKE====== then no ac.

I re routed a smaller belt to not engage the AC, then wound up replaceing the compresor.

Here's some pics if u have to do that.

http://www.utahfordclub.com/rac.htm

I will be doing a whole dryer, orifice tube, 134 conversion this weekend at our SHO club meeting BTW, We will have pics.

N