Australian assembled 240 aircon compressor not engaging

GreenGL

The air conditioner compressor in my 1998 Volvo 240 L.h 2.2 redblock doesn't turn on/engage.

It's an Australian built car with a Nippon Denso compressor (part number seems to have faded off the label), I'm not sure if that was standard fitment for the local built 240?

12V power is making it all the way to the final plug before the compressor clutch, I am suspecting the clutch electrics have packed it in. Would anyone know if these magnetic clutches are replaceable, or its time for a whole new compressor?

jamesinc

GreenGL I take it you mean 1988?

Some 240s use Denso, some Sanden. Older ones York.

The electrical side of the AC system is very simple. Assuming you have gas in your system, when you switch the AC on (to max if you gave a dial rather than switch), you should expect to see 12V at the single wire connector behind the compressor. The wire is usually green or black.

If you don't see 12V, then you would want to test the pins behind the switch, check the pressure switch etc, find out where the circuit is open.

Assuming you are getting 12V, then you know the issue is your compressor clutch. Some models it's easy to change the clutch, some you have to degas the system to do it, not sure what the Denso one is like.

Major Ledfoot

Edit: There's this very good post on TB about 240 aircon systems.
https://turbobricks.com/index.php?threads/the-great-240-ac-system-information-dump-how-to-improve-ac-performance.356477/#post-6106722

Alternative to the Denso compressor is the Sanden SD7 H15 Model 4664 which was used on most B230 engines just before (& well into) the R134a era.

GreenGL

I'm definitely getting 12v to the compressor wire.

Checked the earth wire off the back of the compressor, it's grounding well.

So it's a bad compressor clutch. I was just wanting to know if the clutch is easily serviceable, or if the whole unit needs to be replaced ( in which case I'll just get a workshop to supply and fit a sanden)

jamesinc

Yes, you can replace just the clutch, provided you can get a new clutch assembly for your model. Does the compressor have a part number on it?

GreenGL

jamesinc

Unfortunately the part number seems to have faded off the sticker on top of the compressor unit. I'll get under the car at some stage and see if there's any numbers on the bottom.

TL_V70

Clutches can be easily replaced on most A/C compressors. You just need the right pulling tools to remove and replace them

GreenGL

TL_V70

I assume a 2 or 3 prong/arm puller would be all I need?

Assuming I can get the replacement parts, I'm hoping I can do it in situ. I believe the AC system still has gas in it.

Ex850R

Don’t waste too much cash without proper diagnosing it as a new compressor while not cheap will be good far longer than any 20+ year old one.

TL_V70

One other test youcan do it's a bit dangerous to do with tje car running tho. Win the A/c on and 12v to the clutch you can try taping or pushing the front of the clutch in and see if it engages you will hear an audible click from the compressor if it does.

This is not volvo 240 specific but over time the clutch face and the compressor face wear and the air gap between the two faces is to big for the electro magnetic clutch to engage.

If ypu help it and push it together and it grabs you know its the clutch and depending on the model I know some sanden compressor have removable shims to adjust the air gap behind the clutch plate. If so you could remove 1 or 2 shims to shrink the air gap.

But before you remove the clutch just try to above test.

TL_V70

The first 3 minutes of this videos explains how to remove the entire clutch. When he remove the "HUB" there are normally 2 or 3 small shims directly under it that dictates the air gab between the 2 faces this gap gest bigger with wear and age.

GreenGL

Getting under the car to find a part number on the Nippon denso compressor yielded no results.

I went through the papers that came with the car, the compressor was reconditioned back in 2013.

Might be time to get a shop to supply and fit a sanden 4664

Ex850R

GreenGL

Iceton got me a new one (with warranty) for the 240 , i dont recall the cost but coud be around $500?

Major Ledfoot

What yer MODEL is the car? (Build date isn't year model).

YM 85-87 had the following:
(1324630) replaced by 1395590-1, which was then replaced by 3513066-5.

The YM88-93 parts book shows:
p/n 3513066-5 - 1989-92 R12
p/n 6848094-6 - 1992 R12
p/n 6841028-1 - 1993 R134A --- NOTE! This needs a different bracket (p/n 6842367-2) to the other compressors.

GreenGL

Major Ledfoot

Looks like my car is a 1988 Compliance date/YM88

I will procure the tools to remove the clutch and pulley , might be a break in the wire.

dmc

did you try givi g it a tap or belt when powered? the big end of a large screwdriver would work. if that works then removing a shim might see a few more years of cooling.