+- STD (https://www.superturbodiesel.com/std)
+-- Forum: Maintenance (https://www.superturbodiesel.com/std/forumdisplay.php?fid=22)
+--- Forum: General (https://www.superturbodiesel.com/std/forumdisplay.php?fid=4)
+--- Thread: AC Retrofit problems and questions (/showthread.php?tid=2842)
AC Retrofit problems and questions - MFSuper90 - 08-05-2011
Can anyone tell me what it takes to make a w123 from R12 to 134a?
I put 134a oil in the compressor, but when it idles it rattles like hell and will sometimes even lock up but if you rev it up a couple hundred rpm it acts fine.
Do i need a different expansion valve?
Thanks in advance,
RE: AC Retrofit problems and questions - 98taco3 - 08-05-2011
(08-05-2011, 09:54 AM)MFSuper90 Can anyone tell me what it takes to make a w123 from R12 to 134a?
I put 134a oil in the compressor, but when it idles it rattles like hell and will sometimes even lock up but if you rev it up a couple hundred rpm it acts fine.
Do i need a different expansion valve?
Thanks in advance,
Sounds to me like an overcharged system. Possibly a defective expansion valve not adjusting itself correctly. Blockage in a line somewhere...... Mine did the same thing when i recharged it but has smoothed out since(a/c hadnt worked for a number of years).
Did you change out the receiver dryer before you charged the system? Flush the system of the old R12 compatible oil before you filled with oil and charged it? Did you evacuate the system of air before you charged it? Also, how much oil did you add to the system? did you drain the old oil out first? Just trying to figure out what you did when you converted it...
RE: AC Retrofit problems and questions - MFSuper90 - 08-05-2011
We didnt change the dryer, there was no oil in the compressor, the compressor itself said to fill with 6 oz. so we did. It couldnt be overcharged, it only had about 2 pounds in it (compressor said to use 4) and the dryer sprayed 134a out?? It also blew the big line going to the condenser
RE: AC Retrofit problems and questions - Hercules - 08-06-2011
Correct procedure for conversion. Flush out system using approved flush,install new drier & expansion valve Min. Note (compressor normal life expectancy 5-6 yrs). Drier Same amount yrs.(only can rid system of 5-6 drops of water) then rust occurs,also drier bag can rupture destroying rest of system,drier also catches contaminates and holds oil.evacuating system helps remove water and air from system. 134a runs at different pressures so expansion is also to be changed, use updated seals. update service valves.
Common errors, oils are not compatible,must flush system, (3) diff. weight pag oils use heavier,
Oil still in system through out,Flush system. 12 ozs of oil in system ouch!! compressor is going to hammer(hydraulic knock) at idle,this destroys compressor . Oil charge not determined by compressor but by system size, Look up,8ozs usually for complete system. A/C charge,also by system size,123= 2.6 lbs. A/c charge amount approx.3/4 of r-12, must go by pressures. If all is correct,Still slow to cool,not as cold as r12. Some suggestions,to help cool better,and system to last longer ,Use red pressure switch on drier,turns fan on sooner. Wire fan to high speed.Use larger fan,If poss.Check engine fan clutch for proper operation. Be sure to clean bugs and dirt from radiator & condenser .Poss to use water spray system if in very hot climate. Best of luck .
RE: AC Retrofit problems and questions - MFSuper90 - 08-06-2011
(08-06-2011, 12:28 AM)Hercules Correct procedure for conversion. Flush out system using approved flush,install new drier & expansion valve Min. Note (compressor normal life expectancy 5-6 yrs). Drier Same amount yrs.(only can rid system of 5-6 drops of water) then rust occurs,also drier bag can rupture destroying rest of system,drier also catches contaminates and holds oil.evacuating system helps remove water and air from system. 134a runs at different pressures so expansion is also to be changed, use updated seals. update service valves.
Common errors, oils are not compatible,must flush system, (3) diff. weight pag oils use heavier,
Oil still in system through out,Flush system. 12 ozs of oil in system ouch!! compressor is going to hammer(hydraulic knock) at idle,this destroys compressor . Oil charge not determined by compressor but by system size, Look up,8ozs usually for complete system. A/C charge,also by system size,123= 2.6 lbs. A/c charge amount approx.3/4 of r-12, must go by pressures. If all is correct,Still slow to cool,not as cold as r12. Some suggestions,to help cool better,and system to last longer ,Use red pressure switch on drier,turns fan on sooner. Wire fan to high speed.Use larger fan,If poss.Check engine fan clutch for proper operation. Be sure to clean bugs and dirt from radiator & condenser .Poss to use water spray system if in very hot climate. Best of luck .
Thank you Hercules! You say use 8 ozs of the heaviest pag oil? Do i just put all 8 ozs in the compressor?
RE: AC Retrofit problems and questions - DeliveryValve - 08-06-2011
I always put 4 ounces in the compressor and 4 ounces in the new dryer.
RE: AC Retrofit problems and questions - Hercules - 08-06-2011
Yes use heavier oil,be sure 8 oz is correct amount.R-4 compressor mounted on it"s side,oil would just drain out of compressor if off of car,when re installing. DeliveryValve is correct ,brake up oil charge if poss.Through service valves,(pressured cans),
vac. installed,or open hoses. Wish-ful thinking is Not accepted,lol.
If installing new compressor. Note,the R-4 is a GM designed compressor and was mounted on engine high on right side,Mbz mounted this low on left side, leaving front cover which contains oil drain hole to front bearing upside down, Poor oiling occurred.
Oil hole position is usually marked by arrow or x on front cover outer rim. For longer compressor life oil hole needs to be positioned at top.
RE: AC Retrofit problems and questions - MFSuper90 - 08-07-2011
Hercules,
Where is the expansion valve located on a w123?
And what needs to be done to get the oil hole positioned at the top?
Thanks for all the help,
Eric
RE: AC Retrofit problems and questions - Hercules - 08-07-2011
Expansion valve right side,under glove box,behind kick panel.Use of crows foot (tool) may be helpful.Caution,loosen all lines at , valve first,if poss.before removing valve,This helps support weak evaporator Lines,Try to support valve if lines are tight.
A/c compressor hole, try to find locating mark first,may be ok But usually not.Remove clutch and pulley,(requires puller & installer tools) Remove front cover bolts (4) Pull back front cover,do not remove,turn till oil hole is at top as compressor would be mounted on car, re install. Mount clutch windings plug-in near 5 o"clock position,reinstall all other parts,be sure clutch is properly clearanced 20-40 thousands ok. A little clearance just so does not rub when off. you"re Welcome, All of us needs a helping hand some times!! Compressor will last a while with hole down,diff.oil draining down to bearing or oil trying to be splashed up to bearing through hole. Mbz finally changed this to also drain down.
Expansion valve right side,under glove box,behind kick panel.Use of crows foot (tool) may be helpful.Caution,loosen all lines at , valve first,if poss.before removing valve,This helps support weak evaporator Lines,Try to support valve if lines are tight.
A/c compressor hole, try to find locating mark first,may be ok But usually not.Remove clutch and pulley,(requires puller & installer tools) Remove front cover bolts (4) Pull back front cover,do not remove,turn till oil hole is at top as compressor would be mounted on car, re install. Mount clutch windings plug-in near 5 o"clock position,reinstall all other parts,be sure clutch is properly clearanced 20-40 thousands ok. A little clearance just so does not rub when off. you"re Welcome, All of us needs a helping hand some times!! Compressor will last a while with hole down,diff.oil draining down to bearing or oil trying to be splashed up to bearing through hole. Mbz finally changed this to also drain down.
RE: AC Retrofit problems and questions - MFSuper90 - 08-09-2011
Hurcules, if you ever need any parts for a w123 make sure you let me know, i would be glad to give you a good deal on stuff to return the favor
RE: AC Retrofit problems and questions - Hercules - 08-09-2011
Hey, Thanks! That"s a kind offer. We"re all here to Help each other.
Food for thought, 5,000 years ago,God told Moses to say,"pick up your shovels,mount your asses and camels,and I will lead you to the Promised Land." 75 years ago Roosevelt introduced Welfare and said ,"Lay down your shovels,sit on your asses,light up a Camel,this is the Promised Land."Today,Congress has stolen your shovel,taxed your asses,raised the price of Camels and mortgaged the Promised Land!! What"s this to do with any thing!!! I think they Will be after my MBz Next!!!!! lol.
RE: AC Retrofit problems and questions - MFSuper90 - 08-09-2011
(08-09-2011, 03:34 PM)Hercules Hey, Thanks! That"s a kind offer. We"re all here to Help each other.
Food for thought, 5,000 years ago,God told Moses to say,"pick up your shovels,mount your asses and camels,and I will lead you to the Promised Land." 75 years ago Roosevelt introduced Welfare and said ,"Lay down your shovels,sit on your asses,light up a Camel,this is the Promised Land."Today,Congress has stolen your shovel,taxed your asses,raised the price of Camels and mortgaged the Promised Land!! What"s this to do with any thing!!! I think they Will be after my MBz Next!!!!! lol.
Hahahaha. ^^Agreed on that lol
