99 V70 XC AC Compressor fix ??

Retired MVS Contributor · Post by **Retired MVS Contributor** » 17 Jun 2010, 09:45

Liquid fill into a vacuum, measured by weight, and without the engine running, is the approved method...Vadis recommends filling on the high side...Vapor filling takes MUCH longer because the refrigerant has to be converted back into a liquid again so that it an be stored in the accumulator...For that to happen, the compressor has to be running so that it can pump the vapor through the condenser where it is converted into a liquid...Since the low pressure service port is on the input side of the evaporator, you are circulating the vapor that you just introduced through the evaporator instead of liquid ...

Vapor charging when topping up is slow because the pressure in the can has to exeed the pressure in the system and that means revving the engine to bring the system suction pressure down and suck the vapor in...Allowing can pressure to exceed 50 lbs is dangerous and not recommended...Gages are very helpful but one needs to know how to enterpret their meaning when weighed against ambient temperature, air flow through the condenser, and engine RPM...Revving the engine in FWD cars does not increase air flow through the condenser because the fan is electric and does not increase air flow with increased engine RPM...

The excetion to a liquid top-up is if the engine is running and the suction service port is right on the compressor...Then you can hydro-lock the compressor and damge it...In this case a vapor fill is the correct method...

I retired from the industry in 1993 and have no idea how many A/C's I have serviced, but it is a lot...

C@lvin · Post by **C@lvin** » 17 Jun 2010, 09:53

Back to the original poster's question

......I had the same problem on my 00 V70 (same type compressor/clutch as pictured) a year or two ago. You can fix it with a plastic shim similar to the "bread clip" fix on the older models. I purchased a plastic "For Sale" sign at Wal-Mart that was approximately the same thickness of a bread clip and then cut out the shape I needed for the shims.

PatternFlyer, let me know if you haven't resolved this yet. I will be changing my oil Saturday morning and I can get a picture of it for you......

petek153 · Post by **petek153** » 17 Jun 2010, 13:31

Had the same problem on my sons 94 850 clutch gap only had limited time for a repair so did the getto fix with the plastic clips and used super glue to hold in place figured they would eventually be thrown out but amazed still there after a year working great still.

redsouther · Post by **redsouther** » 17 Jun 2010, 13:46

I did the clutch gap fix on my 00 v70 about 2 years ago. Mine looked just like the one in your pictures, and I was able to do the ghetto fix using bread clips. The trick is to insert the plastic shims under the 3 curved metal pieces on the outside of the clutch plate. Use a screwdriver to push the clutch plate in near each bolt, and insert a shim in the center of the curved piece, working all the way around.

The trick is to get the gap just right. I actually had to flatten the bread clips out with a hammer to make them the correct width. After I found the right width (trial and error), and just used epoxy on each shim to keep it from coming out. My final gap width was around 0.03mm.

Unfortunately, the next summer I started having the same problem again. The shims hadn't come out, but I measured the gap, and found that it wasn't uniform all the way around the clutch plate, so I inserted more shims and that fixed it. Now, another year later, it's doing it again - only worse. Looks like I may be doing the more permanent fix of removing the shims.

Retired MVS Contributor · Post by **Retired MVS Contributor** » 20 Jun 2010, 06:39

There seems to be some misunderstanding about this clutch shim issue---or am I wrong?...The shims are thin washers that are installed on the compressor shaft in back of the clutch...Yes, the clutch has to be removed and in some applications there is not enough room to do that, so the compressor has to be unbolted...The shims adjust the clearance between the pressure plate and the armature by allowing it to move in closer and close up the gap...Shims added at the points shown in the pictues will not stay in place, centrifugal force will throw them out...The engine and compressor normally get very hot...I would think that plastc shims would melt and possibly gum things up...In any event, it would be a short term fix and would not last long...

petek153 · Post by **petek153** » 20 Jun 2010, 06:54

I was thinking they would also be thrown out but we superglued in place and have been in there for over a summer with no ill effects. You are right about the proper way of shimming but time constraints led me to try the plastic shim method and its holding up.

Retired MVS Contributor · Post by **Retired MVS Contributor** » 20 Jun 2010, 08:24

A little story and then I am going to forget this shim issue...

Years ago when I worked in the collision industry another shop in the area took in a front end damage job...The radiator had been pushed in and the fan was bent...Instead of replacing the fan they bent the blade back straight...They did not notice that there were fatigue cracks where it was bent...After the car was started the mechanic working under the hood revved the engine...The blade snapped off and pierced his chest, killing him instantly...

I would be concerned that these glued shims can get thrown by centrifugal force...While they would not kill anyone, they certainly could put an eye out...CrazyGlue is fantastic in straight pull/stress, but it fails miserably in sideways shear stress...It will be placed in shear during clutch engagement...We DYer's have to be careful we don't hurt ourselves in an effort to save a few dollars...

Jerry

theblacklantern · Post by **theblacklantern** » 10 Jun 2011, 07:15

Greetings. I have experienced the classic problem of losing my ac and getting that damp smell. As the weather heats up the duration of run time decreased to 10 min or less. I replaced the accumulator (turned out it was full of crud) and a high side pressure switch, but still saw no improvement of performance,
After much fooling around and spending money on parts I didn't need, the bread clip fix has solved my ac problem. Attached is a photo of my compressor and the placement of the bread clips. Didn't have to cut them any special way. Just slid them in evenly under each leaf spring and did a dab of super glue gel. My original gap was +0.8mm! Can't believe the clutch came on at all. My final gap after shimming was 0.2mm. A bit slim, but it seems to be working just great at that tolerance. Only a few days later we we had over 100 degree temps (yes this is MN!) for 2 days and it pumped out cold air faithfully! Should be a good summer!
Good luck to all and God bless this easy ghetto fix![img][img][/img][/img]

C@lvin · Post by **C@lvin** » 10 Jun 2011, 07:59

I hadn't considered that particular location for the shim. Here is a picture of my shim using a cut out piece of sheet metal. Either way narrows that gap which makes all the difference in the world when we're having August weather in June!

https://www.matthewsvolvosite.com/forums ... 0&start=28