A simple question with no straight answers, as it seems.

Does the old style (-1990) expansion valve have to be changed when converting to R134? Or, rephrased: Are there two different valve types, exclusively designed for R12 and R134 respectively? I know an old valve should be changed when you get in there but that´s another story...

The ball bearing conversion of my blower motor went perfect, btw. Nowadays I only listen to the sound of cold air coming out of the vents...and position 1 is enough most of the time. The conversion required something like one hour in the garage and two (SKF) bearings at $4 each.

Also noticed that the motor (80's style with tre mounting ears) had felt rings around the original bushings. Two older motors (70's, in sheet metal enclosure) I disassembled didn't have these rings. Guess that would be a significant factor for success if you try to lube an old motor to get rid of the noise - the oil or grease just won't stay for long in the older style motor but I think the felt rings will keep newer motors lubed for a pretty long time. That could explain the varying results from lubing reported here and elsewhere.

/Martin

If you use Freeze12 there are NO conversion concerns! No hardware considerations.

Many a post here on the board mentions you only need to change the expansion valve. The R12 evaporator is not big enough to properly cool using 134A.

The easiest conversion is to use Freeze12. R12 performance at 134A prices.

The usage of Freeze12 is hypothetical for me since it isn't available here - after R12 was forbidden, R134 has been the only alternative. But that's not all bad - swedish shops now are as good at working with R134 as they were with R12 before, parts are always designed for R134, there are no mix-up risks, pricing is ok and so on.

When it comes to cooling matters of my own car, I suspect some differences in the R12 and R134 designs to be the real problem. If I run the AC hard, the return line and U-bend inside the car will freeze despite of how much hot air I blow through the evaporator. It won't get cooler than that, no matter what refrigerant you use...

The air, however, could get cooler. A faulty or just plain old expansion valve maybe is one possible explanation, but what about the distance between the valve and the evaporator? All R12 systems I've seen have minimal distance between these parts where (original) R134 cars have at least one feet of tubing between the orifice tube and the evaporator.

That is, what if the real cooling starts when the R134 is half way through the evaporator because of this difference? No wonder the air never gets colder than 45 deg F.

Just a thought...

/Martin

Martin -

I have heard both ways on the expansion valve. When it's my time to convert I will not change the EV, and run the system. If it turns out I am right, no new EV and no installation labor. If I'm wrong, then it'll cost the EV, the labor, and a re-charge of RS134.

Regarding the blower motor. Can you please post all the identifying info about the SKF bearings you used, and any other tips on that upgrade.??

Thanks and regards,

Bob

:>)

I installed AC when rebuilding the car (this is in Sweden where literally no 240's have got original AC) and of course used R134 since all the parts had been on the floor anyway and R12 was forbidden in 1996 or so. But even though the return line gets freezing cold (snowy!), the air doesn't seem to get REALLY cold and that's why I'm asking about the expansion valve which I didn't change. The compressor and condensor are newer 900/700 parts and the heater valve (new style) ok.

The bearings are standard dimension (8 mm inner dia), for some reason often labelled 608 and available from severable manufacturers such as SKF, Toko and a german brand I can't remember. There are sealed and open types available, I guess the sealed ones are right on spot for this purpose.

Installing the bearings is simple - use a bench vise (vice in UK?) to remove the old bushing, spring and cover plate from each end of the motor housing. The new bearings are 22 mm (outer dia) and the housing ends 24 mm (inner). I used a strip of 1 mm sheet alloy to reduce the diameter at each end and then the vise again, you choose method by yourself. Wrench sockets will act like fine distances in this work. Finally, the axle will need some polish or sanding with a VERY fine grade paper. The bearings don't have to sit that tight - just enough not to play around. To tight will give you trouble when trying to disassemble or adjust the shaft location axially.

There was actually no problems performing this conversion and considering the time required to get to the motor, one or two hours more doesn't matter. A problem not related to the bearings, anyway, is worn commutator (and brushes) - not that easy to fix and you of course want the motor to last 'til the end of time'. I sorted mine out of three to get a fresh one...

/Martin

73 165E

65 121 4d

i don't think there's a difference, but i replaced mine as i did my work. the part should cost around 25$$ and will only add about i extra hour to total time. the one thing that was told to me about replacing it was to connect the pigtail piecr to a different spot than it came from. find the 'U' shaped tube that the flexible connector connected to and wrap the pigtail a wrap or two around the U-tube and tie it off so that the pigtail is touching this tube.