Automotive Air Conditioning Information Forum (Archives)

rebar on Thu June 11, 2015 9:11 AM

Year: 1995
Make: ford
Model: E350
Engine Size: 5.9
Refrigerant Type: 134a
Ambient Temp: 75
Pressure Low: 39
Pressure High: 260
Country of Origin: United States

Hello. Im getting 60 degree's discharge air and the air flow doesn't feel to strong in my ford van. I hung a sheet behind the seats.
If the air temp was 45, the cfm might be sufficient, but I have a two fold problem maybe. Lack of cfm and something in my AC system not performing. All the components are clean on the outside. My condenser is behind my intercooler.

I disconnected my heater core with no change in discharge air temp.

After a drive to test if isolating the core helped, I found it was idling at about 50 psi low side, and dropped down to mid 40's when I revved the engine to 2000 rpm. My red line is about 2700 rpm.
At first I thought I over charged it because I was at 40 psi at idle when I charged it, but now wondering if my compressor is tired as I heard it making some intermittent wobbling noise's I'm not used to hearing especially at idle. I did not check the high side psi at that moment.
Do compressors loose suction as they warm up if going bad?

Maybe I should never have left the system empty for a year while I rebuilt the engine? But I had the same dismal performance before the rebuild.

This is a repowered van which used to have a gas engine and the ford compressor was used. Most of the time I'm cruising under 2000 rpm. Do diesel AC clutch's have smaller pulleys to compensate for the lower engine rpm?

Where should I start to look if everything is clean and all fan speeds work? I also have confirmed the outside air damper is closed for recirculation when on Max AC.

Thanks!


-------------------------
95 E350 6bt/nv4500

Edited: Thu June 11, 2015 at 12:30 PM by rebar

TRB on Thu June 11, 2015 11:00 AM

In AZ we never could get these vans to cool well. Poor insulation and a ton of heat from the engine bay creates poor a/c conditions.

-------------------------

When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

rebar on Thu June 11, 2015 1:27 PM

Quote
Originally posted by: TRB
In AZ we never could get these vans to cool well. Poor insulation and a ton of heat from the engine bay creates poor a/c conditions.

Thanks.. My cargo is insulated and paneled and the sheet behind the front seats should help allot.

So everything sounds normal? And the only additional thing I can do is add a rear AC?

I cant understand why my low side can fluctuate from 35 when I charged it, to 50 after a hot drive



-------------------------
95 E350 6bt/nv4500

Edited: Thu June 11, 2015 at 1:29 PM by rebar

bohica2xo on Thu June 11, 2015 7:37 PM

Ok, nothing about that van is "normal".

You stuffed a Cummins in it. The subtle "repower" in your title goes right by many.

To start with your high side is way too high for 75f ambient. Mounted behind the intercooler is a lousy place for the condensor - it was designed for ambient air flow temps.

A great mechanical fan with a good shroud might help with the condensor issues. What do you have for a fan now?

The second issue is that the blend & direction doors on that vehicle run on vacuum. A common failure is a bad check valve on a gasser - you get most of the air on the defroster vents with low or no vacuum. Do you have all of the vacuum hoses connected? On vehicles that old, Ford used nylon spaghetti lines in places. After 20 years they get brittle & crack - did you move a bunch of lines near the A/C box during the swap?

Finally, Ford trucks & Vans of that vintage are well known for sucking up dirt from the passenger footwell. Blocked evaporators are common. Pet hair, gum wrappers, leaves, a dead mouse - I have found all of that and more in E/F series evaporators.



-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

rebar on Mon June 15, 2015 1:29 PM

Quote
Originally posted by: bohica2xo
Ok, nothing about that van is "normal".



You stuffed a Cummins in it. The subtle "repower" in your title goes right by many.



To start with your high side is way too high for 75f ambient. Mounted behind the intercooler is a lousy place for the condensor - it was designed for ambient air flow temps.



A great mechanical fan with a good shroud might help with the condensor issues. What do you have for a fan now?



The second issue is that the blend & direction doors on that vehicle run on vacuum. A common failure is a bad check valve on a gasser - you get most of the air on the defroster vents with low or no vacuum. Do you have all of the vacuum hoses connected? On vehicles that old, Ford used nylon spaghetti lines in places. After 20 years they get brittle & crack - did you move a bunch of lines near the A/C box during the swap?



Finally, Ford trucks & Vans of that vintage are well known for sucking up dirt from the passenger footwell. Blocked evaporators are common. Pet hair, gum wrappers, leaves, a dead mouse - I have found all of that and more in E/F series evaporators.

Thanks bohica.

This van isn't a daily driver. It was built to haul my 9500 lb 24' toyhauler to Colorado at 75 mph.

The only fan it has is the stock cummins fan and clutch. Granted, its not the best. But again, the van is designed for the interstate. One day I hope to install a larger intercooler so that would be the time to move the condenser in front and add fans. But that might drive my exhaust temps higher. No time for that now as I'm leaving for colorado in august.

I tested all of my vacuum servos and they are operating correctly, but I cant see the dampers themselves. The defrost vents don't blow air when AC is on, but do when defrost is on and I can see the outside air damper close for inside recirculation. Iv inspected and cleaned the condensor and evap. I have disconnected the heater core and connected the two engine tube's together. I have a new blower motor and cage, resister, red orifice tube and accumulator/drier on the way and hope my system doesn't have the ford black death but will know more when I disassemble and service it.

[URL=http://s640.photobucket.com/user/re-rod/media/4726AE49-6426-4FF2-9E5B-D64AC23EB197_zpswl0rtmgc.jpg.html][/URL][URL=http://s640.photobucket.com/user/re-rod/media/19C3BD37-E523-4F9B-B7A1-AB7DC7519B94_zps1q501m68.jpg.html][/URL][URL=http://s640.photobucket.com/user/re-rod/media/D9067CD1-A6C9-4FC3-9E17-94FBE621680B_zpszewa02cn.jpg.html][/URL][URL=http://s640.photobucket.com/user/re-rod/media/FA0685DC-6FC6-4E0A-9C3D-D4353F70C101_zpsqq2wfddy.jpg.html][/URL]

Thanks again for your time.



-------------------------
95 E350 6bt/nv4500

Edited: Mon June 15, 2015 at 1:30 PM by rebar

Dougflas on Mon June 15, 2015 6:47 PM

Does the high side drop like a rock if you mist the condenser with a garden hose? If so, you have an inefficient condenser/condenser airflow.

Edited: Mon June 15, 2015 at 6:47 PM by Dougflas

rebar on Wed June 17, 2015 11:01 AM

Quote
Originally posted by: Dougflas
Does the high side drop like a rock if you mist the condenser with a garden hose? If so, you have an inefficient condenser/condenser airflow.

I already suspect my airflow isn't sufficient while driving in town, but I will give that a water trick a try when I get the system back together.

Mean while, I removed the accumulator/drier and orifice tube which was installed in the correct direction. I don't smell or see the ford black death, but I do see a few metal flakes on the orifice tube screen along with the black deposits which might explain my 39/260 psi condition.

Should I simply flush everything except the compressor? Or do those flakes mean my compressor is about ready to fail?



Thanks

http://i640.photobucket.com/albums/uu127/re-rod/2ED7A436-B310-47E6-A586-6A660F84B55C_zps6zacdkx6.jpg

-------------------------
95 E350 6bt/nv4500

HECAT on Wed June 17, 2015 11:13 AM

I would flush everything being reused, replace the compressor, OT, and accumulator.

-------------------------

HECAT: www.hecatinc.com You support the Forum when you consider www.ackits.com for your a/c parts.

FLUSHING TECHNICAL PAPER vs2.pdf 

rebar on Thu June 18, 2015 7:41 AM

Quote
Originally posted by: HECAT
I would flush everything being reused, replace the compressor, OT, and accumulator.

Actually, the shinny specks on my O-tube are not metal confirmed with a magnet. I think they might be the Teflon used in the compressor?

I blew Interdynamics aerosol Power Clean and Flush through the old school tube in fin condenser and it had nothing in it except oil. So I feel pretty confident the orifice tube was the only thing wrong.

But now I'm worried about the Interdynamics Professional-Grade Aerosol Flush. It says blow out residual solution, which I did but It was never dry. There was always a little stream of solution still coming out. And even though the instructions state a vacuum will boil off the remainder, Iv read here a vacuum will not.

Do I need to remove the condenser and tip it upside down and continue to blow since its a low spot? Or simply leave it uncapped so it can evaporate?

All this work to flush correctly makes me want to ignore the rest of the system since I don't have the ford black death and only a clogged O-tube.



-------------------------
95 E350 6bt/nv4500

HECAT on Thu June 18, 2015 8:49 AM

IMHO, the aerosol flushes contain just enough solvent with dismal flow to be a solvent injector; not a flusher. The reason you did not see any metal particulates when you flushed (if they are there); is this type of product cannot produce the liquid flow velocity to move them. In most cases the spray cans just contain a cheap white solvent (aka mineral spirits), which is a decent solvent for mineral oil, but not so with PAG or POE oils used with R134a.

The air blow to blow out recommended solvents is usually a full blow (direct air line connected) with dry air (filtered) for 20 to 30 minutes. If any solvent is running out or solvent mist is still present, more air blowing is required. The vacuum process can only remove some minimal trace residues, excessive solvent will dilute the vacuum pump oil and possibly damage the vacuum pump.

-------------------------

HECAT: www.hecatinc.com You support the Forum when you consider www.ackits.com for your a/c parts.

FLUSHING TECHNICAL PAPER vs2.pdf 

rebar on Thu June 25, 2015 12:58 PM

I flushed both evap and cond with lacquer thinner in reverse and saw a few black deposits come out of the cond. Both are installed and I'm on my second evac. After a few more gas flushes, in the low and out the high, Ill pull vacuum for the last time and draw the oil in. If that's ok.

New accumulator, Orifice tube , O rings , oil and blower.

My question is about charging now. Ford says 44 oz 134a refrigerant. But can I add a few extra oz and expect it to stay in the accumulator? Do I need to be exactly 44 oz or is a touch extra for deminimis gauge removals and what not a good idea?

Thanks!

Do I draw my oil into the accumulator?

-------------------------
95 E350 6bt/nv4500

Edited: Thu June 25, 2015 at 2:15 PM by rebar

bohica2xo on Thu June 25, 2015 3:26 PM

Did you drain the compressor? New Compressor? Either way, pour oil in to the suction side of the compressor with the system open. Rotate the compressor shaft (clutch plate) 6 to 10 revolutions to clear the cylinders.

Close the system up and evacuate. 44 to 46 ounces of refrigerant should be fine.

I prefer to charge the bulk of the refrigerant as liquid in to an evacuated system through the high side, with the engine stopped. You can push more than 50% of the charge in this way before you ever start the engine. With no risk of degreasing the compressor, since the discharge check valves will only let the refrigerant enter the condensor from the high side port.

Once you have the bulk charge in, close the highside handwheel on your gauge set before starting the engine.

Once the engine is running start the compressor,and finish charging through the low side as vapor. Let it cycle, do NOT jumper it to run full time.



-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

rebar on Thu June 25, 2015 3:52 PM

Quote
Originally posted by: bohica2xo
Did you drain the compressor? New Compressor? Either way, pour oil in to the suction side of the compressor with the system open. Rotate the compressor shaft (clutch plate) 6 to 10 revolutions to clear the cylinders.



Close the system up and evacuate. 44 to 46 ounces of refrigerant should be fine.



I prefer to charge the bulk of the refrigerant as liquid in to an evacuated system through the high side, with the engine stopped. You can push more than 50% of the charge in this way before you ever start the engine. With no risk of degreasing the compressor, since the discharge check valves will only let the refrigerant enter the condensor from the high side port.



Once you have the bulk charge in, close the highside handwheel on your gauge set before starting the engine.



Once the engine is running start the compressor,and finish charging through the low side as vapor. Let it cycle, do NOT jumper it to run full time.

Old drained compressor. But I left the hose block on.

Iv already done the triple evac but my local AC specialist says I might slug the compressor if I put all the oil in the low side.

Should I really break vacuum and add to compressor? Or can a put 2 oz in high and 4 oz in low safely ?





-------------------------
95 E350 6bt/nv4500

Edited: Thu June 25, 2015 at 4:22 PM by rebar

bohica2xo on Thu June 25, 2015 4:47 PM

You will only have it open for a few minutes. Vacuum it back down. You want to pull the vacuum on the oil to remove any trapped air or moisture in the oil.

The reason you turn the compressor by hand for 6 to 10 revolutions is to prevent slugging it. This moves the oil through the compressor to the discharge line. The inside of the compressor will be well coated at startup, but the hand turning clears the cylinders of excess liquid.



-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

rebar on Thu June 25, 2015 6:31 PM

Quote
Originally posted by: bohica2xo
You will only have it open for a few minutes. Vacuum it back down. You want to pull the vacuum on the oil to remove any trapped air or moisture in the oil.



The reason you turn the compressor by hand for 6 to 10 revolutions is to prevent slugging it. This moves the oil through the compressor to the discharge line. The inside of the compressor will be well coated at startup, but the hand turning clears the cylinders of excess liquid.

OK I broke vacuum and added oil at the compressor, pulled vacuum and added oil to accumulator and high side port evenly.

I then added 45 oz 134a on highside. 3/4 the charge engine off and the remainder while idling from low side.

Now I have 30 psi/ 190 psi. ??

I'm tempted to add more, but 45 oz is 45 oz..

Why is my low-side running so low? It dipped into the 20's when I revved it up, and I have the feeling I might be at the same pressure's I started out with, if I add 134a until the low side is 40.

Wow.



-------------------------
95 E350 6bt/nv4500

bohica2xo on Thu June 25, 2015 6:55 PM

So what is your ambient temperature? Vent temperature?

30 & 190 at idle sounds ok to me, depending on ambient temp.

Set the cabin fan on highest speed, and open both doors. run the engine at 1500 rpm & check the pressures.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

rebar on Thu June 25, 2015 9:28 PM

Quote
Originally posted by: bohica2xo
So what is your ambient temperature? Vent temperature?



30 & 190 at idle sounds ok to me, depending on ambient temp.



Set the cabin fan on highest speed, and open both doors. run the engine at 1500 rpm & check the pressures.

Ambient was 85 vent was 52 idling. My pressures were 34 and 210 after I added a extra 2 oz of refrigerant , so I went for a drive since my condenser fan is marginal.

I waited until I get some air speed on the interstate and turned AC on. I had 49 degree vent air. I pulled into town 45.. 35 mph.. Then smelled smoke. Something was smoking, hot!

I turned the AC off and pulled over and popped the hood. I then turned the ac back on and my clutch was clearly slipping and hot as hell. I get it back home and cooled it with wet rag, removed belt and the compressor spins nice but the clutch is clearly trashed and wobbly..

Well, at least my system might be ok and I need a new clutch.. Question is.. Why did clutch fail just now?



-------------------------
95 E350 6bt/nv4500

bohica2xo on Fri June 26, 2015 2:39 AM

1) Why did you add refrigerant? Pressures were good.

2) This is the OEM Ford compressor. How many miles are on it? How is the belt tension applied?

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

rebar on Fri June 26, 2015 6:58 AM

Quote
Originally posted by: bohica2xo
1) Why did you add refrigerant? Pressures were good.



2) This is the OEM Ford compressor. How many miles are on it? How is the belt tension applied?

1) Because I was running 25/195 at 85 ambient revving 1500-1700 rpm after adding 45 oz 134a. To me , it was undercharged according to this chart.
http://acprocold.com/faq/r-134a-system-pressure-chart/
But both pressures were spread to far apart according to the chart. Or, I should never had a 170 psi spread at 85 ambient making me wonder if my condenser side has a problem still.

2) The van has 275K on the chassis and the engine has a fresh rebuild. The previous owner said the AC system had been serviced and was functioning, but I don't know any details.. The cummins automatic belt tensioner provides tension.

I removed the single bolt and clutch and the pulley bearing is very wobbly and shot. I haven't removed the snap ring yet wondering if I'm wasting more time..

If my condenser wasn't sandwiched between the radiator and intercooler, would my pressures be closer to 50/240 the chart shows?

Thanks again.


-------------------------
95 E350 6bt/nv4500

Edited: Fri June 26, 2015 at 7:55 AM by rebar

mk378 on Fri June 26, 2015 10:32 AM

Is the compressor able to turn, is the static pressure holding? If it seized up or you find the front of the compressor got hot enough to melt the seal and cause a leak, you would replace the whole unit.

You really need to do something about the condenser. When you're driving, the intercooler will be making heat, so it's still not good. I think the 95 had a piccolo condenser-- a slight improvement over the "old school tube and fin" but a true parallel flow mounted up front is really what you want.

bohica2xo on Sat June 27, 2015 1:35 AM

Compressor idler bearings fail. Sometimes with no relationship to the rest of the system. It is even possible the compressor had 200k on it.

Throw that chart in the trash. The charge weight on a CCOT system is what you should use. Too much additional charge backs up in the condensor, and drives pressures up, while decreasing cooling.

Higher pressures don't improve cooling. The low side pressure is controlled by the cycling switch at low ambient temperatures. The low high side you posted is actually good news. It means that the OEM cummins fan is moving quite a bit of air, and that you may get away with the condensor behind the intercooler.

If the system still has pressure, you can put a bearing in the pulley. Sounds like you are not afraid of a little mechanical work.

Just put the charge back to 45 ounces. 25 on the low side makes cold air.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

rebar on Sat June 27, 2015 9:23 AM

Quote
Originally posted by: mk378
Is the compressor able to turn, is the static pressure holding? If it seized up or you find the front of the compressor got hot enough to melt the seal and cause a leak, you would replace the whole unit.



You really need to do something about the condenser. When you're driving, the intercooler will be making heat, so it's still not good. I think the 95 had a piccolo condenser-- a slight improvement over the "old school tube and fin" but a true parallel flow mounted up front is really what you want.

The compressor still turns nicely and is holding the refrigerant charge, but it sure got hot.
I would love to relocate the condenser in front of the intercooler, but I don't have the time for that project before I head out to colorado. From what I understand, the evo has the IC in front of the condenser, and it has little impact on that system's ability to cool.
But if and when I relocate the condenser, I need to replace my intercooler with a larger unit but nothing stock bolts into my van other than my small 1st gen dodge from what I can find. I'm also unsure how to fabricate custom AC piping for the relocation. I'm experienced working with copper but not fabricating steel piping with the quick disconnects my ford has.

Quote
Originally posted by: bohica2xo
Compressor idler bearings fail. Sometimes with no relationship to the rest of the system. It is even possible the compressor had 200k on it.



Throw that chart in the trash. The charge weight on a CCOT system is what you should use. Too much additional charge backs up in the condensor, and drives pressures up, while decreasing cooling.



Higher pressures don't improve cooling. The low side pressure is controlled by the cycling switch at low ambient temperatures. The low high side you posted is actually good news. It means that the OEM cummins fan is moving quite a bit of air, and that you may get away with the condensor behind the intercooler.



If the system still has pressure, you can put a bearing in the pulley. Sounds like you are not afraid of a little mechanical work.



Just put the charge back to 45 ounces. 25 on the low side makes cold air.

OK sounds like a plan.

I just need to find that Compressor idler bearing for a reasonable price.

30mm x 55mm x 23mm, I think.

SKF Part # 5106WCC $36

FOUR SEASONS Part # 25204 $28

Do I need to replace the clutch as well after it got hot? Or just remove enough washers to get the correct gap?

Thanks!



-------------------------
95 E350 6bt/nv4500

Edited: Sat June 27, 2015 at 11:02 AM by rebar

bohica2xo on Sat June 27, 2015 6:43 PM

The price for a genuine SKF is not bad.

Chinese bearings are cheaper, but some say they are not as good:
VXB bearings 55x30x23

The clutch is ok if the coil is not shorted, open, or damaged. Re shim it to the minimum gap. A clutch is fine at .010 inch gap as long as it does not hit in one spot.

.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

rebar on Sun June 28, 2015 7:39 AM

Quote
Originally posted by: bohica2xo
The price for a genuine SKF is not bad.
Chinese bearings are cheaper, but some say they are not as good:

VXB bearings 55x30x23
The clutch is ok if the coil is not shorted, open, or damaged. Re shim it to the minimum gap. A clutch is fine at .010 inch gap as long as it does not hit in one spot.
.

I think my compressor needs replaced due to all the parts now damaged.
Hate to give up on the old gal.. But, yeah.. Unless I can replace the coil and clutch for under $100
I imagine, that I might still have a American made compressor? Was there ever such a thing?



So I guess I better start a new thread topic. "Help me build a new bullet proof AC system" Or something like that. I want to do this right but the reliability of the compressors these days makes me wonder if its worth the time..

-------------------------
95 E350 6bt/nv4500

bohica2xo on Sun June 28, 2015 12:18 PM

Yeah, that one is dead. Good news is an NEW FS10 is around 200 bucks with a clutch.

FS10's do ok. If they are working hard on a big vehicle like a van, they will not last as long as they do in a Mustang.

Without big upgrades to the condensor, and adding a second evaporator, your best choice is to keep the stock system.

Now, if your motto is "go big or go home", then yeah you can build a killer system. How far do you want to go/

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.