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Dash ac oil [message #319335] Tue, 20 June 2017 12:30 Go to next message
Larry is currently offline  Larry   United States
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My dash AC has been making a "clunking" sound lately. Asked an AC guy about it and he said that it likely needed some more AC oil. (my word not his). How much should I add and how?

Thanks


Larry Smile
78 Royale w/500 Caddy
Menomonie, WI.
Re: Dash ac oil [message #319336 is a reply to message #319335] Tue, 20 June 2017 13:51 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
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Larry, oil type depends upon your installed refrigerant. R12 and HC12a use mineral oil, NAPA TEM 209500. R134a use ester oil. The oils are not compatible. If you have converted to R134a, you can go anywhere (Wal-Mart, Menards, auto parts stores) and purchase a can that goes in the low port.
I don't know about installing mineral oil. I do need to know. I need to install new A6.
Tom, MS II running the Honda and the overhead air.


2012 Phoenix Cruiser model 2552 KA4CSG
Re: [GMCnet] Dash ac oil [message #319340 is a reply to message #319336] Tue, 20 June 2017 14:11 Go to previous messageGo to next message
Richard Denney is currently offline  Richard Denney   United States
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Tom, R134 systems use PAG oil, if they were installed by a shop that
flushed the system or in newer cars. PAG oil is indeed not compatible with
mineral oil used in R12 systems. But ester oil is compatible with both.
Ester oil is an alternative for systems converted from R12 that might have
traces of mineral oil in them.

Larry, if it just needs a little, you can get a can of refrigerant with the
oil mixed in, but only R134 these days. If you are using HC12A/Duracool,
both mineral and ester oil will work, but ester oil might be the safer bet
if you don't know what's in it and it just needs to be topped up. You can
evacuate the system and pour the oil right into the back of the compressor.

I seem to recall (and this is a fuzzy memory) that only a pint is used in
the system and maybe even less (I'm visualizing the bottle in my dim memory
and it might have been 10-12 ounces), so it should not take much to top it
off. But you'll have to open the system. The question is: Where did the oil
that was in it go? Losing compressor oil isn't common.

Rick "who, come to think of it, needs to charge his system and see if it
works" Denney

On Tue, Jun 20, 2017 at 2:51 PM, Thomas Phipps wrote:

> Larry, oil type depends upon your installed refrigerant. R12 and HC12a use
> mineral oil, NAPA TEM 209500. R134a use ester oil. The oils are not
> compatible. If you have converted to R134a, you can go anywhere (Wal-Mart,
> Menards, auto parts stores) and purchase a can that goes in the low port.
> I don't know about installing mineral oil. I do need to know. I need to
> install new A6.
> Tom, MS II running the Honda and the overhead air.
> --
> 1975 GMC Avion
> KA4CSG
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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--
'73 X-Glacier 230 "Jaws"
Northern Virginia
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Re: Dash ac oil [message #319342 is a reply to message #319336] Tue, 20 June 2017 14:32 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Mineral oil is available at any HVAC supplier warehouse and some decent auto parts stores. I seriously doubt that this is the source of your noise. I would look at the heater fan. That fan will loosen up on the shaft, wear, and clunk. Auto Zone has new ones.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: Dash ac oil [message #319343 is a reply to message #319335] Tue, 20 June 2017 14:43 Go to previous messageGo to next message
TR 1 is currently offline  TR 1   United States
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If you're looking to get R12 Refrigerant Oil charge. it's still readily available on ebay. Here's just one auction I found, but if you search for R12 refrigerant oil, there are quite a few auctions:

http://www.ebay.com/itm/Refrigerant-R12-Oil-Charge-4oz-MFG-Sercon-part-6512-/122556242943?hash=item1c88ebdbff:g:50IAAOSwAuZX1c1O&vxp=mtr

It's a little pricey, but not terribly expensive. As a guy who lives in Texas and has several older vehicles with R12 AC, there are more "deals" on R12 related stuff if you shop during the winter... Wink

You can also often find R12 locally on Craigslist as well...


Mark S. '73 Painted Desert, Manny 1 Ton Front End, Howell Injection, Leigh Harrison 4bag and Rear Brakes, Fort Worth, TX
Re: Dash ac oil [message #319351 is a reply to message #319335] Tue, 20 June 2017 17:02 Go to previous messageGo to next message
Larry is currently offline  Larry   United States
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OK...Thanks all for the replys. I have a Duracool system and talked to a Midwest Classics member that does AC for a living. He told me to add 4oz of ester into the system with a new Dryer.

Ken, the "clunking" noise that I described is definitely not the fan...checked that out. Noise is only there when AC compressor clutch engages, and goes away when engine speed increases. Friend told me he had heard it many times and easiest check is to just add some oil to the system. So I'm gonna just pour 4 oz into the dryer, vac it down and recharge. I pulled a vac on it this morning and held 29" for 1/2 hr, so system is tight.

Anyway...thanks all.


Larry Smile
78 Royale w/500 Caddy
Menomonie, WI.
Re: Dash ac oil [message #319369 is a reply to message #319351] Wed, 21 June 2017 06:43 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Larry wrote on Tue, 20 June 2017 17:02
OK...Thanks all for the replys. I have a Duracool system and talked to a Midwest Classics member that does AC for a living. He told me to add 4oz of ester into the system with a new Dryer.

Ken, the "clunking" noise that I described is definitely not the fan...checked that out. Noise is only there when AC compressor clutch engages, and goes away when engine speed increases. Friend told me he had heard it many times and easiest check is to just add some oil to the system. So I'm gonna just pour 4 oz into the dryer, vac it down and recharge. I pulled a vac on it this morning and held 29" for 1/2 hr, so system is tight.

Anyway...thanks all.

Well, So much for my guess at the problem. My only problem with adding oil is it is possible too load up the dryer with excess oil from the system. It should not need oil unless some of it has leaked out. If it leaked then you will also be low on freon.

I ran into a problem once on Dan Gregg's coach. It only happened when the clutch was engaged. It turned out that it had a belt that was too long allowing the clutch to slightly drag on the cross brace next to it. I believe you have a Cadillac engine so this probably does not apply to you.



Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: Dash ac oil [message #319373 is a reply to message #319369] Wed, 21 June 2017 08:47 Go to previous messageGo to next message
Larry is currently offline  Larry   United States
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Ken Burton wrote on Wed, 21 June 2017 06:43
Larry wrote on Tue, 20 June 2017 17:02
OK...Thanks all for the replys. I have a Duracool system and talked to a Midwest Classics member that does AC for a living. He told me to add 4oz of ester into the system with a new Dryer.

Ken, the "clunking" noise that I described is definitely not the fan...checked that out. Noise is only there when AC compressor clutch engages, and goes away when engine speed increases. Friend told me he had heard it many times and easiest check is to just add some oil to the system. So I'm gonna just pour 4 oz into the dryer, vac it down and recharge. I pulled a vac on it this morning and held 29" for 1/2 hr, so system is tight.

Anyway...thanks all.

Well, So much for my guess at the problem. My only problem with adding oil is it is possible too load up the dryer with excess oil from the system. It should not need oil unless some of it has leaked out. If it leaked then you will also be low on freon.

I ran into a problem once on Dan Gregg's coach. It only happened when the clutch was engaged. It turned out that it had a belt that was too long allowing the clutch to slightly drag on the cross brace next to it. I believe you have a Cadillac engine so this probably does not apply to you.


Ken, for various reasons, I've had to drain and refill the system about 4 times in the last year. Oil has come out each time. I'm hoping that all it needs is a little oil. Will be adding 4oz today sometime. Thanks for the suggestions though. Every little thought helps.


Larry Smile
78 Royale w/500 Caddy
Menomonie, WI.
Re: Dash ac oil [message #319384 is a reply to message #319335] Wed, 21 June 2017 10:00 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Oil charge cans are the obvious fast easy way to go here. If really low causing the noise, adding One can should clear it up. More is not better at it starts to take the place of refrigerant. It's often found on eBay as R12 oil charge if you are running R12 or added HC12 to an R12 system. Auto parts store if running 134a.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: Dash ac oil [message #319390 is a reply to message #319373] Wed, 21 June 2017 10:54 Go to previous messageGo to next message
roy1 is currently offline  roy1   United States
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Larry you really need too know if it has pag oil ester oil or mineral oil in the system you don't want to mix mineral with the first two. I believe the dura cool people say they have an oil that is compatible with all three of these but that is all I know about it.you may want too call them.

Roy Keen Minden,NV 76 X Glenbrook
Re: Dash ac oil [message #319393 is a reply to message #319390] Wed, 21 June 2017 11:27 Go to previous messageGo to next message
Larry is currently offline  Larry   United States
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roy1 wrote on Wed, 21 June 2017 10:54
Larry you really need too know if it has pag oil ester oil or mineral oil in the system you don't want to mix mineral with the first two. I believe the dura cool people say they have an oil that is compatible with all three of these but that is all I know about it.you may want too call them.

Roy,
I have a half of a can of ester in with my AC stuff, so it is safe to assume that this is what is left over from the last time I added oil. Thanks for the comment.


Larry Smile
78 Royale w/500 Caddy
Menomonie, WI.
Re: Dash ac oil [message #319697 is a reply to message #319335] Tue, 27 June 2017 22:38 Go to previous messageGo to next message
RoadWarrior is currently offline  RoadWarrior   United States
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If you still have cold air it is very unlikely you are low on oil. You might check the lines and see if there is any signs of refrigerant oil around the fittings.

A possible cause of your "Clunk" could be that the compressors clutch is out of adjustment. I believe the procedure is in the service manual, but it does take special tools to make the adjustment.
Re: Dash ac oil [message #319700 is a reply to message #319697] Wed, 28 June 2017 07:32 Go to previous messageGo to next message
Larry is currently offline  Larry   United States
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RoadWarrior wrote on Tue, 27 June 2017 22:38
If you still have cold air it is very unlikely you are low on oil. You might check the lines and see if there is any signs of refrigerant oil around the fittings.

A possible cause of your "Clunk" could be that the compressors clutch is out of adjustment. I believe the procedure is in the service manual, but it does take special tools to make the adjustment.

OK, I'll check that too. Thanks!!


Larry Smile
78 Royale w/500 Caddy
Menomonie, WI.
Re: Dash ac oil [message #319702 is a reply to message #319335] Wed, 28 June 2017 08:14 Go to previous message
JohnL455 is currently offline  JohnL455   United States
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Single clunk most likely clutch and some noise is normal. Hammering at running speed is normal if faint and abnormal if loud. I have had luck with reducing noise on A6 and R4 w R12 by adding a single small can of oil charge. You can do the matchbook test as a rough initial check of compressor clutch gap while off and not running.

John Lebetski
Woodstock, IL
77 Eleganza II
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