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roybelding
roybelding, Shop Foreman Freightliner trucks
Category: Medium and Heavy Trucks
Satisfied Customers: 4646
Experience:  Shop Froeman for Freightliner Trucks
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I have 1999 international 9400 with Detroit. 60. I have

Customer Question

I have 1999 international 9400 with Detroit. 60. I have replace every thing from the clutch fan all low and high pressure switch compressor and I still can't get the clutch to engage when the head pressure reaches 350 psi it will cut the compressor off. I've check for restrictions in the system and none.
Submitted: 8 months ago.
Category: Medium and Heavy Trucks
Expert:  roybelding replied 8 months ago.

good evening my name is ***** ***** I will assist

it is supposed to cut off at that pressure. what is the low side pressure when it hits 350???

how much freon did you install?? too much freon will cause this

give me any info you can

Roy

Customer: replied 8 months ago.
3 lbs not sure. About the low side maybe 70 to 90
Expert:  roybelding replied 8 months ago.

low side way too high. it looks like it is way overcharged. high side should be outside temp plus 15% and the low side 25-40 lbs max

Customer: replied 8 months ago.
Did you mean 25 to 30 lbs
Expert:  roybelding replied 8 months ago.

25-40 lbs on the low side, yes

Customer: replied 8 months ago.
It has a york compressor . I was told by dealer service dept 36ozs or 3 lbs that is high. My freighliner only required 3.5 lbs. I will need to continue this once I verfi the low side psi
Expert:  roybelding replied 8 months ago.

ok

Customer: replied 8 months ago.
I meant 25 to 30 is high. I will need to get back with you i don't feel that is right
Expert:  roybelding replied 8 months ago.

yes it is. anything below 20 lbs and the system will freeze up. been doing ac for over 35 years

Customer: replied 8 months ago.
At the beginning you indicated that it was over charge I'm lost
Expert:  roybelding replied 8 months ago.

when it is overcharged, the pressures will be too high on both sides like you have according to your post

Customer: replied 8 months ago.
But I only have 3lbs in the System but you are saying I'm over charge how do you get that if I don't have enough
Expert:  roybelding replied 8 months ago.

your words said 3 lbs not sure???????? this was in your post

Expert:  roybelding replied 8 months ago.

I am here and not there to check it. you are my eyes and my info and go on that info.

I would start from scratch and remove the freon, vacuum for 30 minutes and add exact amount called for according to the sticker

Customer: replied 8 months ago.
It call for 3lbs yes I have vacuumed the system down
Expert:  roybelding replied 8 months ago.

ok, try hosing down the condenser and see if the pressures drop

so your now saying it is definitely 3 lbs and you are sure

Customer: replied 8 months ago.
3lbs and placed shop fan in the front of condenser and yes it brought the the psi down. But the clutch fan never engaged when it got to 350 psi
Expert:  roybelding replied 8 months ago.

ok, then theres is your issue. have you bypassed the fan solenoid to see if it works???

you replaced the binary switch??

once you get the fan running the pressures will return to normal

roy

Customer: replied 8 months ago.
Soleniod switch is new, not sure of the binary switch location and what it does
Expert:  roybelding replied 8 months ago.

I didnot ask if it was new, I asked if you bypassed it to see if the fan works

it ison the passenger side by the dryer. it contains the low pressure and high pressure switch that signals the fan solenoid to engage. you said you already replaced it in your original post??????

Customer: replied 8 months ago.
It has one high pressure on the compressor which is new also two on the expansion value which new also new expansion value
Expert:  roybelding replied 8 months ago.

ok, I am sorry, I cannot continue. you keep giving me info that is either maybe or not sure and you doubt my pressure readings. I am trying to help and keep finding new info you never indicated. you have not answered whether you bypassed the fan as you said it wont come on. you did not cool down the condenser with water and give me the readings.

without info I cannot help you get to a resolution. I will re post for you and hopefully you will give accurate info to the next guy.

good luck, I hope you get it straightened out.

Customer: replied 8 months ago.
I sorry u couldn't help. The pressure drop to 245psi
Expert:  roybelding replied 8 months ago.

I can help if you give me the info I request. I new it would drop, what about the low side??? the fan???

Customer: replied 8 months ago.
I will give that infor tomorrow if that's ok
Expert:  roybelding replied 8 months ago.

ok, go ahead. I am ready

Customer: replied 8 months ago.
Ok bypass soleniod it engaged . on thel ow side 32psi
Expert:  roybelding replied 8 months ago.

ok, so the fan works and the low side came down. is the air nice and cold now???

Roy

Customer: replied 8 months ago.
High side is 350 and it cuts the compressor off
Customer: replied 8 months ago.
Only If I override the fan with a Manuel switch
Expert:  roybelding replied 8 months ago.

ok, if you have a water hose, hose down the condenser on the front of the radiator and see if the high side comes down

Customer: replied 8 months ago.
Ok stand by
Customer: replied 8 months ago.
its down to 245 - 250
Expert:  roybelding replied 8 months ago.

good, we are moving in the right direction.

clean out the condenser and the radiator ral good. you may need to use a comb for this. if you dont have it then take it to a car wash and use high pressure wash with hot soapy water to clean out all the fins of debris. not enough air going through radiator to cool down the freon.

then the fan control needs to be dealt with to get the fan working right

Customer: replied 8 months ago.
Ok I have pressure washer
Expert:  roybelding replied 8 months ago.

good

Customer: replied 8 months ago.
OK pressure washer and air dry it with shop air blower about the same. Temp outside is around 65 temp from vent is 52.
Expert:  roybelding replied 8 months ago.

52 not bad. was there much dirt in the fins????

Customer: replied 8 months ago.
To be truthful not excessive. A few fins at the top was close maybe about 1/4 or little less of the entire condenser
Expert:  roybelding replied 8 months ago.

can you feel a good draw of air into the radiator with the engine running???

Roy

Customer: replied 8 months ago.
when fan is on by the manual switch
Expert:  roybelding replied 8 months ago.

ok, after the pressure wash, is the high side still over 300

Customer: replied 8 months ago.
If I turn the fan off it rises to 350 yes but a little slower
Expert:  roybelding replied 8 months ago.

it should, the fan needs to run to lower the high side.

have you had the fan checked as to why it wont start on its own??? or do you just turn it on manually

Roy

Customer: replied 8 months ago.
Well that was one of the problems it would never signal the fan to come on to cool the condenser to keep the head pressure down
Expert:  roybelding replied 8 months ago.

ok, you did replace the fan solenoid?? did you verify power to the solenoid??? the control is the coolant sensor. that signal is sent to the ecm and the ecm will turn on the fan

roy

Customer: replied 8 months ago.
No I didn't but I did notice at 209 degree the clutch fan engaged to cool the engine down
Expert:  roybelding replied 8 months ago.

ok, thats the correct time. so with that in mind the ac still goes high with the fan on???

Customer: replied 8 months ago.
It will reach 250 psi with fan on
Expert:  roybelding replied 8 months ago.

250 is a good pressure. what does the low side do when it is at 250

Customer: replied 8 months ago.
32-40
Expert:  roybelding replied 8 months ago.

still a tad high.

I would start by removing the freon, vacuum for 1 hour and adding exactly the amount needed again

Roy

Customer: replied 8 months ago.
OK I will do that. Be in touch tomorrow
Expert:  roybelding replied 8 months ago.

sounds like a plan

Roy

Customer: replied 8 months ago.
Vacuum system down it held . Recharge unit with recommended amount which is 36 ozs. Yesterday was a warm day had to run fan on high.
Expert:  roybelding replied 8 months ago.

ok, which fan??? inside or outside??? what was the temp at the vent???

Roy

Customer: replied 8 months ago.
Inside 58 degree outside 84
Expert:  roybelding replied 8 months ago.

ok, is that the temp of air coming out the vent or the temp inside the truck??

Customer: replied 8 months ago.
Vent
Expert:  roybelding replied 8 months ago.

thats not too bad. it should be around 52. rev the engine up and see if it gets colder.

what are the pressure readings??

Customer: replied 8 months ago.
This temp is driving at 68 mph
Expert:  roybelding replied 8 months ago.

ok, got it.

the next thing is the mode door. can you see if the mode door is fully closed for ac and not letting anything from the heater core coming in

Roy

Customer: replied 8 months ago.
I will need to remove the passenger seat and check
Expert:  roybelding replied 8 months ago.

should not have to.

Customer: replied 8 months ago.
It's an international the blower fan and evaporator also doors are there
Expert:  roybelding replied 8 months ago.

yep, I know it is a pain in the butt to get to

Roy

Customer: replied 8 months ago.
All doors r working fine . I took it to WW WILLIAM and now I have cold air and my clutch engaged for around 180 sec it's working fine.
Expert:  roybelding replied 8 months ago.

what did they do???

Customer: replied 8 months ago.
ECM wasn't communicating to clutch fan and pressure switch
Expert:  roybelding replied 8 months ago.

you said the ac clutch was activating??? does that mean all this time the clutch was not engaging????

Roy

Customer: replied 8 months ago.
No I said the fan clutch would not come on went the head pressure got high and it would cut the compressor clutch off but it would come on at 209 to cool the engine down
Expert:  roybelding replied 8 months ago.

yes, but as you said just now, the clutch was working

anyway. its fixed and glad you are back on the road

Expert:  roybelding replied 8 months ago.

good luck to you

Customer: replied 8 months ago.
Ac clutch would stay on until the head pressure got high and once that happen it would shut down
Expert:  roybelding replied 8 months ago.

once the head pressure gets high, it is supposed to shut down to protest the system. thats what the high pressure switch is supposed to do

Customer: replied 8 months ago.
that was the problem in the early part of the post around the 18th post
Expert:  roybelding replied 8 months ago.

yes it was. I read it all. thats what we were trying to get to. it is supposed to do this. that is the problem with me being here and not there to see it for my self and do the actual diagnostic.

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