V8 owners - anyone use a 'deslugger' on their A/C compressor?

[Reprise]

(<on edit:> There's a YT vid by the vendor explaining what this thing does, but it doesn't give much more than what I posted below (it's only 3-4min long). But if anyone requests it, I'll post that link, too.)

For those wondering what in the nine hells a 'deslugger' is... here's a link that shows the product...

Amazon.com: 4 Seasons 36141 Compressor Clutch Timer: Automotive

Amazon.com: 4 Seasons 36141 Compressor Clutch Timer: Automotive

www.amazon.com

The 'why'.... for vehicles that have a low-mounted A/C compressor (GMs with LS-based motors, among other makes / models) -- after using the A/C, then parking the vehicle "for 30min or more", oil & refrigerant drains down into the compressor, causing a high resistance on the compressor when the vehicle is next started (potentially affecting the clutch, bearing, relay, belt / tensioner, etc.) This is apparently called 'slugging' the compressor.

What this thing does is apply a PWM voltage to the compressor when the A/C is first energized, so that it purges any accumulated material before allowing full voltage to the compressor.

Why I was interested in it -- I'm expecting that my compressor (or, at least the clutch / bearing and/or relay) on my Sierra is going to be toast, given that the belt is missing and the tensioner is shot.

As I was pricing replacement parts, I came across this item. (Rock references it, which is how I found out about it -- but I don't think they sell it - ?)

(Yes, I will test my system before simply assuming the compressor is shot. I also purchased a set of manifold gauges & a vacuum pump a few days ago, in prep for rebuilding / repairing the A/C)

I figure if I'm going to have to replace part / all of the compressor, I might as well put an ounce of prevention in place.
Note that Amazon is *not* the cheapest source for these, btw.

With all of that out of the way -- anyone have one of these on their (V8) truck?
(from what I understand, the 4.2's compressor is mounted high on the opposite side of the V8 trucks, so this would be of limited use on those vehicles)

 

[littleblazer]

The air in the sierra hasn't been turned off since day one... can't say I've experienced this problem. The factory belt threw off 2 years ago but otherwise hasn't been touched.

 

[Mounce]

Pwm? So it slips the clutch? I wouldn't allow that on such an expensive part. Seems like it'll prematurely wear the clutch to save the internals, might as well let natural selection have its way. AC compressors are application designed units generally speaking, if there was an issue with it being at the bottom then they wouldn't put them there or would design them to handle it I would think.

Also, first I'm hearing of this device. I had seen on a Tahoe once where there was a factory name/style box and sticker installed that would run the hvac fan for 30 seconds after shut down to stabilize the freon or something silly. I don't recall finding much about it when researching it at the time.

 

[Reprise]

Pwm? So it slips the clutch?

Not sure if I'd call it 'slipping' the clutch (although it might be the same as the TCC valve in the trans, eh?) Supposedly, it applies a lower voltage, for a short period of time (milliseconds), gradually increasing the time over 4-5 cycles. The video (@ 3:21) at the following link shows an example of the widening pulse width.

I think I saw them for about $30 on eBay. At that price, I may take a shot. The one for the Sierra is pre-terminated with male / female plugs, so it's an inline plug-and-play deal.

If it works, it'll be a lot cheaper / less effort over replacing the compressor again.
If it doesn't -- I still have $70 from what I saved on not buying the IR rattle gun...LOL

The Deslugger

The Deslugger Compressor Clutch Timer

www.4s.com

 

[Mooseman]

Idk. Sounds like a solution to a non existent problem. Afaik, refrigerant is in a gaseous state at rest in the system and I think you'd need all the oil in the system to hydrolock the compressor. And reading around a bit, seems to affect older ones with pistons.

If we really had a problem of failing compressors, there'd be more talk about it and OEMs would be doing something to.prevent it.

Just my 2¢ (rounded down to 0 since we don't have pennies anymore)

 

[Reprise]

Sounds like a solution to a non existent problem.

Funny you'd write this...last night, when I did my last post on this, I envisioned someone saying "solution in search of a problem". Great minds... LOL

You know, I've read about & had people tell me in person about compressor issues with the f/s pickups, plus I've got issues to resolve. So I jumped (?) to the conclusion that it was somewhat prevalent. Even people with their 360s seem to have A/C issues (and now that I've said that, watch my Envoy's system go south -- I've already been thinking it doesn't seem to be as 'frosty' this summer, as it's been in past years.)

However, reading / hearing about a few instances, relative to the 300-500 THOUSAND that GM sells of these trucks, every year (I'll estimate 75% have some form of a V8; no idea where the compressor is mounted on the V6 trucks) -- it stands to reason that occurrences of 'slugging' are probably rarer than I've led myself to believe. Figured I'd ask if anyone else had heard of these; until last week, I hadn't.

 

[NJTB]

I think it's snake oil. Worked in the business 20 years (70's to 90's), heard of it, never saw it myself.
'

 

[m.mcmillen]

I think the majority of vehicles have the compressor mounted at the bottom. It could be that there is the possibility of this problem and the manufacturers are aware of it and they’ve programmed the PCM to do what this device does.

 

[TJBaker57]

I would say that as far as slugging a compressor in an automotive system goes it is far far more likely to have happened due to someone adding too much refrigerant. STOP adding refrigerant "just because"! More is definitely NOT better here. Slugging a compressor in stationary systems is definitely an issue and on large systems we install refrigerant piping systems with multiple traps to distribute the compressor oil into smaller quantities that are easily handled by the compressor at startup.

Also, refrigerant in a system will migrate to the coldest point in the system. Always. That's where it will condense into a liquid. After running the system for a while that coldest point will likely be the evaporator coil.

My take on it at least. (HVAC Journeyman by trade)

 

[m.mcmillen]

STOP adding refrigerant "just because"!

Yes! It drives me crazy when I hear someone say that they just “added a can” because it wasn’t working. There’s so many other things that can go wrong besides having a low charge.