cooling problem
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cooling problem
2002 F250,heavy duty.
problem,ac cools while driving at night or even on a cloudy day but on a hot sunny day you have to run on max and even then will not cool cab.I had gas checked they said it was good to go.I bought this truck new and the ac has always been weak in my opinion.I took it to dealer the first summer I owned it everything checked out ok. Any ideas what the problem might be?
problem,ac cools while driving at night or even on a cloudy day but on a hot sunny day you have to run on max and even then will not cool cab.I had gas checked they said it was good to go.I bought this truck new and the ac has always been weak in my opinion.I took it to dealer the first summer I owned it everything checked out ok. Any ideas what the problem might be?
More Turbo
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From: W. Wisc
Well if the system pressures are in the right range for the ambient temps (and I am assuming here that they were checked for real with a pair of AC gages and not just one of those "AC miracle in a can" gages), then the sealed system is probably performing correctly.
That puts you into a couple possibilities:
1. Inadequate cooling to the condensor. Could be a weak fan clutch or obstructed condensor.
2. Obstructed airflow in the ducts in the cab. The evap could be blocked partially by debris or plastic that got sucked in. The blend door could be malfunctioning allowing heated air in when you want just AC.
Some thoughts. I'd start with #1. Find a hot sunny day when the AC is not cooling well. Pull into your driveway and mist the condensor with a hose. Does the AC work great suddenly? Then I'd look at obstructed airflow or bad fan clutch.
If you haven't got real AC gages onto it, I'd do that next.
-Dave
That puts you into a couple possibilities:
1. Inadequate cooling to the condensor. Could be a weak fan clutch or obstructed condensor.
2. Obstructed airflow in the ducts in the cab. The evap could be blocked partially by debris or plastic that got sucked in. The blend door could be malfunctioning allowing heated air in when you want just AC.
Some thoughts. I'd start with #1. Find a hot sunny day when the AC is not cooling well. Pull into your driveway and mist the condensor with a hose. Does the AC work great suddenly? Then I'd look at obstructed airflow or bad fan clutch.
If you haven't got real AC gages onto it, I'd do that next.
-Dave
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I don't believe in miracle cures I just asked a question. Sorry I won't ask anymore.thanks for the help dstig1 I appreciate the reply.
More Turbo
Joined: Aug 2006
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From: W. Wisc
Don't take it too personally - it fit the pattern since you didn't give us more info to go on. Seen it too many times myself...
One thing that can cause poor performance is overcharging, and it can happen from the factory. You might need to have a shop be a bit more precise in testing the pressures. I say this, as I see you have owned this from new and have apparently had the problem all along.
You need to get 3 numbers from a test: 1. Ambient air temp where the truck is being tested 2: Low side pressure 3: high side pressure. The pressures bounce around as the compressor cycles, but they will tend to stabilize in a range - tell us what those number are. Also need to know if the clutch is cycling and what the rough time on/time off is.
Could still be something plugged under the dash - like a piece of plastic stuck to the condensor. I know it's hard but have you tried to check there? Your issue really reads like inadequate performace from blocked airflow, but overcharging is another possibility.
Hopefully something comes of that.
-Dave
One thing that can cause poor performance is overcharging, and it can happen from the factory. You might need to have a shop be a bit more precise in testing the pressures. I say this, as I see you have owned this from new and have apparently had the problem all along.
You need to get 3 numbers from a test: 1. Ambient air temp where the truck is being tested 2: Low side pressure 3: high side pressure. The pressures bounce around as the compressor cycles, but they will tend to stabilize in a range - tell us what those number are. Also need to know if the clutch is cycling and what the rough time on/time off is.
Could still be something plugged under the dash - like a piece of plastic stuck to the condensor. I know it's hard but have you tried to check there? Your issue really reads like inadequate performace from blocked airflow, but overcharging is another possibility.
Hopefully something comes of that.
-Dave
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I did notice one time when I had hood open that the clutch on compressor was kicking in / out very often maybe every 10-15 seconds.Maybe the gap between plates is wrong or worn. question,how do I get to condensor I know nothing about ac systems .what are the cooling coils in front of radiator.I replaced the blend door in my 1997 F150 a couple of years ago and that was no fun at all.
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More Turbo
Joined: Aug 2006
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From: W. Wisc
Whoops - typo on my part - I meant to say Evaporator, not condensor. The condensor is the part in front of the radiator. The evap is under the dash. About the same amount of fun to access as the blend door was, but you really only need to look at it, not take it out.
You can check the clutch gap with feeler gages -should be 0.014-0.030". If it's above 0.030 or close to it, then remove a shim. but you've had the problem since new, so that seems unlikely - but it's easy to check.
If your clutch is cycling every 10-15 sec in hot weather (85+) then you definitely have a problem. On a cool day that would even be on the short side of cycle time. That points to inadequate airflow over the condensor or low charge or restriction in the low pressure side. But we'd need more info to confirm what is going on.
If you can't diagnose this yourself - and it appears you don't have the tools or experience - at this point, you are better off finding a good AC shop and making sure they address the problem and don't go "it's good!" It's much harder to diagnose things like this over the internet than in person.
You can check the clutch gap with feeler gages -should be 0.014-0.030". If it's above 0.030 or close to it, then remove a shim. but you've had the problem since new, so that seems unlikely - but it's easy to check.
If your clutch is cycling every 10-15 sec in hot weather (85+) then you definitely have a problem. On a cool day that would even be on the short side of cycle time. That points to inadequate airflow over the condensor or low charge or restriction in the low pressure side. But we'd need more info to confirm what is going on.
If you can't diagnose this yourself - and it appears you don't have the tools or experience - at this point, you are better off finding a good AC shop and making sure they address the problem and don't go "it's good!" It's much harder to diagnose things like this over the internet than in person.
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Hey i have a 89 f150 and my gauage on my coolant says tthat that truck truck is running hot soon as i turn on the truck its like 3/4 of the way up and after driving for a bit its way past the hot mark the truck is still running fine and everything seems to be in order but i can't figure what might be doing i tried changing the thermostat cause the truck was taking awhile to warm up but it didint' do anything it seems to sometimes jump ( the gauage i mean) but doesn't seem to be doing anything else its like the gauage wants to go back to where it should be going but wont for some reason got any ideas as to what it might be
Cargo Master
Joined: Jun 2003
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From: Somewhere Saskatchewan
Hey i have a 89 f150 and my gauage on my coolant says tthat that truck truck is running hot soon as i turn on the truck its like 3/4 of the way up and after driving for a bit its way past the hot mark the truck is still running fine and everything seems to be in order but i can't figure what might be doing i tried changing the thermostat cause the truck was taking awhile to warm up but it didint' do anything it seems to sometimes jump ( the gauage i mean) but doesn't seem to be doing anything else its like the gauage wants to go back to where it should be going but wont for some reason got any ideas as to what it might be