A/C Clutch Not Fully Engaging - Clutch Brush?

ricer333 · 01-13-2013, 10:47 AM

Ok, I'm hoping it's as simple as that. Here's the issue. I have had the A/C Clutch and the A/C Compressor (Tecumseh 850) both rebuilt by the guys out at Classic Auto Air in Tampa, FL. They returned the compressor filled with the proper amount of Ester oil to run R134a in the system.

I pulled a vacuum on the system and it held for a week plus. I filled the system as per the recommendations of everyone I have asked; roughly 21 oz of R134a - recommended by CAA in Tampa.

When working on the 2nd can, the g/f turned the A/C temp all the way to 5 (full blast) and the A/C clutch caught only for a few seconds (~5-7). The rest of the time the clutch seemed to be sparking/arching on the drivers side of the brush at the top. It almost seemed like the brush was not able to pull in the clutch long enough.

In that instance that the clutch was pulled in, I was able to get the low side to around 35 psi and the high side was just under 200 psi. The temp outside yesterday was around 78 F, so I believe the system is properly charged. Also, while during that 5-7 seconds when the clutch was engaged, the g/f in the car said that the temp dropped down to 60 F (little tester thermostat in the fins of the Evaporator).

The rest of the time, the clutch just seemed to tweak out. The bet was still spinning just the clutch seemed to be hanging.

So, is it as simple as replacing the A/C Clutch brush that sits on top? Anyone ever seen this arching/sparking that I'm talking about?

Thanks!

65fastback6 · 01-13-2013, 10:52 AM

When I was rebuilding mine I noticed the brushes had a lot
of build up on them and were sticking, so I cleaned them and
was able the free them up, so make sure yours can move
freely with the spring action.

22GT · 01-13-2013, 01:36 PM

Quote:

Originally Posted by ricer333

So, is it as simple as replacing the A/C Clutch brush that sits on top? Anyone ever seen this arching/sparking that I'm talking about?

Many times. If the brushes are moving freely, you can tweak the ends of the bracket to move them into contact with the slip rings.

ricer333 · 01-13-2013, 01:55 PM

Quote:

Originally Posted by 22GT

Many times. If the brushes are moving freely, you can tweak the ends of the bracket to move them into contact with the slip rings.

Does the material wear over time, similar to brake pads? They both seem to spring in, towards the firewall just fine, but it seems like they don't pertrude out far enough to make contact... Especially the passenger side one (top one in pic)

ricer333 · 01-13-2013, 02:26 PM

Quote:

Originally Posted by 22GT

Many times. If the brushes are moving freely, you can tweak the ends of the bracket to move them into contact with the slip rings.

Does the material wear over time, similar to brake pads? They both seem to spring in, towards the firewall just fine, but it seems like they don't pertrude out far enough to make contact... Especially the passenger side one (top one in pic)

65fastback6 · 01-13-2013, 02:58 PM

Quote:

Originally Posted by ricer333

Does the material wear over time, similar to brake pads? They both seem to spring in, towards the firewall just fine, but it seems like they don't pertrude out far enough to make contact... Especially the passenger side one (top one in pic)

They don't wear very much, the one I spoke of was an original
and it still had plenty of brush left.

Is your clutch installed on all the way?
The brushes get pushed in maybe 3/16"
when the clutch is seated on all the way.
You shouldn't have to bend the bracket to
make it go in further but you can give it a shot.

ricer333 · 01-13-2013, 05:34 PM

Quote:

Originally Posted by 65fastback6

They don't wear very much, the one I spoke of was an original
and it still had plenty of brush left.

Is your clutch installed on all the way?
The brushes get pushed in maybe 3/16"
when the clutch is seated on all the way.
You shouldn't have to bend the bracket to
make it go in further but you can give it a shot.

I'm pretty sure the clutch is on all the way. The drivers side piece of material is grabbing touching the clutch.

22GT · 01-13-2013, 06:01 PM

Move the brush toward the clutch.

Gas_Pumps · 01-13-2013, 06:55 PM

Did CAA replace the brushes etc. as part of the rebuild? If so, I would talk to them before doing anything. They have always been great to deal with and know what they are doing. Good luck.

ricer333 · 01-13-2013, 07:35 PM

I never sent them the brushes or if I did they just sent them back with the old parts that were not used. I was going to call them and talk to them tomorrow, just figured I'd try to ask here first.

As far as the other post above, can/should I just shim the passenger side closer to the clutch as that is the side that does not seem to be coming into contact with the brass ring on the back?

65fastback6 · 01-13-2013, 08:57 PM

Quote:

Originally Posted by ricer333

As far as the other post above, can/should I just shim the passenger side closer to the clutch as that is the side that does not seem to be coming into contact with the brass ring on the back?

I would take the brush assy off and make sure the brushes
move freely and that you feel the spring action.

ricer333 · 01-13-2013, 10:23 PM

Quote:

Originally Posted by 65fastback6

I would take the brush assy off and make sure the brushes
move freely and that you feel the spring action.

So I'm trying to get the brush assembly off. How do I prevent the clutch from spinning when trying to break the bolt loose that holds it onto the compressor? I I turned the ignition to on, turned the fan on along with the temp and heard the clutch click, but it was not enough to keep it from moving when I applied force to remove the bolt.

65fastback6 · 01-13-2013, 10:43 PM

Quote:

Originally Posted by ricer333

So I'm trying to get the brush assembly off. How do I prevent the clutch from spinning when trying to break the bolt loose that holds it onto the compressor? I I turned the ignition to on, turned the fan on along with the temp and heard the clutch click, but it was not enough to keep it from moving when I applied force to remove the bolt.

The center part that engages has to be held while you loosen the bolt,
they make a tool to do that but I'm sure you don't have one.
Maybe you can come up with something that can hold it.

22GT · 01-13-2013, 11:18 PM

If you use an impact wrench, the inertia of the hub does the job. But try it with a wrench and your hand, first.

ricer333 · 01-14-2013, 07:13 AM

Quote:

Originally Posted by 65fastback6

The center part that engages has to be held while you loosen the bolt,
they make a tool to do that but I'm sure you don't have one.
Maybe you can come up with something that can hold it.

Thanks, I found a tool that seems to fit the job, just trying to see if Autozone has one for rent.

Something hit me last night and wanted to ask. Is it possible that when I put the clutch brush back onto the compressor, that I put it in upside down? If you look at the picture, the rivet holes are visible and I'm wondering if they are supposed to be pointing down?

This could explain why the drivers side (lower side in the picture) is making contact with the clutch plate but not the passenger side (higher side in the picture).

Or do both pieces move in dependent of one another, so it wouldn't matter at all what way it was put back in?

Either way, I'll be pulling the clutch off when I get the tool and taking a look at the piece. Stupid question: Pulling the clutch will not release any of the R134a that I have in the system right? That's all sealed up, right?