I have a 98 Blazer 4x4 with a/c problems. Last few years it has been leaking slowly and would need a large can of freon (134a?) at beginning of Summer. By the next Summer it would be low enough the compressor would NOT engage.

By end of last Summer it would need it again a few times. I saw the pressure switch (up at the silver canister) was leaking so I changed that switch w new one. Seemed to "fix" it for a few weeks. Then would not hold pressure more than a day. Being it was late Sept I just left it til this Summer.

Was just told by ac tech that the compressor is bad. Said that it has "good discharge" but "no pull on suction side". Wants to replace compressor/clutch for $204.99 parts. $113 labor and $55 to evacuate & refill.

Are there parts (seals, o-rings etc) on the compressor that are replaceable/re-buildable to solve the "no pull on suction side"?

What's odd to me, that when the system was refilled it would cool like a champ. No idea where the freon was leaking. Does a "no pull on suction side" mean the freon was leaking somewhere? If not then what does it mean?

 

"no pull on suction side" along with "good discharge" could mean any one of several things, a bad clutch is NOT one of them. If the system is low on charge, the low side, or as some call it, the suction side, will be low, and to a "rookie" A/C tech, high side might appear "normal" when in fact it is also low. If your compressor is the original, it is a Harrison model HT6 and looks like this:


It has an extremely high failure rate for the case seal leaking. Eventually they all leak, some sooner than others. They can be rebuilt, but why bother? There are other aftermarket compressor manufacturers that have "bolt on" compressors that are designed differently and don't leak. Bottom line, you'll spend less money.

 

Thanks for the reply Captain.

Can you recommend a replacement brand that is "bolt on" that is designed differently and doesn't leak?

 

The common problem with the HT6 compressors is that they have a two piece case. The halves are sealed with an O ring. The ends of the compressor are bolted to a bracket leaving little support at the joint, and the O ring leaks. This compressor is made by Sanden. It's a direct bolt on aftermarket replacement. The obvious difference is that the Sanden uses a one piece case making it stronger and eliminating the need for an O ring. As with any mechanical part, eventually it will fail, but I have not had a problem with these....yet

 

Thanks again Capt. Sanden prices are much higher from what I have seen so far.

Now off to find a "primer" online on how to set up a new compressor.

Anyone have a link to a good one?

 

Just picked something up in your post. You said you changed the switch on the low side cause it was leaking, More likely then the switch leaking it was the shrader valve behind it, the one that is actually inside the accumulator. The repair kit that AZ has is 3.99. It comes with two valve cores and a valve core tool. Two caps are also included but you will not need them.
Just a thought.

 

A leaky shrader valve in the accumulator for the cycling switch would not cause an external leak. The cycling switch uses that passage to sense accumulator pressure. A leaky O ring on the outside of the fitting would cause a leak though. I've seen several cycling switches leak too, had to replace my own just last week UV dye is a wonderful thing

 

I had tried to get a new o-ring, but it was easier to find a new switch with a new o-ring.

How easy/cheap is it to get a light to see the uv dye? My system still has the dye in it - I am just curious to see whatever I can see.

If the oem compressor is leaking at the case seal, would it just show up outside the compressor?

They also had put in some refrigerant and the system *was* making cold air last night. Not sure if it all leaked out yet today.

 

E-bay is the cheapest, Amazon the most reliable. If you go E-bay go with a top rated seller that ships from the US. Talk about a slow boat from China, you will get your order, guaranteed, BY CHRISTMAS.
If you have a dark garage you can get away without the yellow glasses, anyplace in daylight you really should get them.

 

You can grab a quick UV inspection kit at a lot of auto parts stores. I got mine at AutoZone last summer. It included a UV penlight, yellow glasses, and possibly something else. I think it was about $12. That has been sufficient for the a/c work I've done so far.