air-conditioning spf mk2
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If the air was initially cold and then became warm you most likely have leakage in the system. Usually o ring connections. Use a leak detector dye. Second possibility is icing in the evaporator due to air and moisture still in the system when charged. A strong vacuum needs to be pulled for 2 hours or more before charging with r134a.
If you don't have a A/C gauge manifold set to troubleshoot, you should get one. I picked one up for about $50 and it has helped me solved two car A/C problem very quickly.
One issue similar to yours was the airgap in the compressor clutch - the A/C would run cold until the car warmed up and then blow warm. I pulled a shim to tighten the gap and the unit blows cold all the time now. The other issue was a relay that had corrsion on it and wasn't cycling the compressor. This caused intemittent operation of the A/C.
I found the troubleshooting of the compressor clutch on the compressor manufacturer's website...it was very helpful giving all kinds of things to check. Do you know what brand and model number your compressor is?
Mike
One issue similar to yours was the airgap in the compressor clutch - the A/C would run cold until the car warmed up and then blow warm. I pulled a shim to tighten the gap and the unit blows cold all the time now. The other issue was a relay that had corrsion on it and wasn't cycling the compressor. This caused intemittent operation of the A/C.
I found the troubleshooting of the compressor clutch on the compressor manufacturer's website...it was very helpful giving all kinds of things to check. Do you know what brand and model number your compressor is?
Mike
this is the diagnostic tool I was referring to:
- Harbor Freight Tools - Quality Tools at the Lowest Prices
- Harbor Freight Tools - Quality Tools at the Lowest Prices
SPF supplied compressor is a Sanden.
Steve,
My recent experiences fixing two of my car's A/C issues were helped with the use of the Gauge Manifold setup that I was describing. In both of my cases, I was able to see that the amount of refrigerant was sufficient and that the compressor was working fine when engaged. This lead me to figure out why the compressor was not engaging consistently.
I have not had issues with the GT40 (yet).
The compressor that I had the clutch gap issue (was in a jeep cherokee) was a Sanden. Here is a link to their website service manual in .pdf which is very helpful:
Sanden USA: Service Manual
The relay issue was in a VW Passat - it has been working reliably for a few months now since I took the compressor relay out and cleaned the contacts.
Mike
My recent experiences fixing two of my car's A/C issues were helped with the use of the Gauge Manifold setup that I was describing. In both of my cases, I was able to see that the amount of refrigerant was sufficient and that the compressor was working fine when engaged. This lead me to figure out why the compressor was not engaging consistently.
I have not had issues with the GT40 (yet).
The compressor that I had the clutch gap issue (was in a jeep cherokee) was a Sanden. Here is a link to their website service manual in .pdf which is very helpful:
Sanden USA: Service Manual
The relay issue was in a VW Passat - it has been working reliably for a few months now since I took the compressor relay out and cleaned the contacts.
Mike
I can't speak about 2117, but 2120 is fine, very fine.
I have had a few issues with the protective film starting to come off in a few places...and two nice rock chips (I wasn't given touch up paint from Superformance). That and the fact that I don't drive it as much as I should....
When I do drive it, my hear rate goes up dramatically...it is a blast!
Regards,
Mike
I have had a few issues with the protective film starting to come off in a few places...and two nice rock chips (I wasn't given touch up paint from Superformance). That and the fact that I don't drive it as much as I should....
When I do drive it, my hear rate goes up dramatically...it is a blast!
Regards,
Mike
I just drove 2214 to Reno and back (1200 round trip) and the AC worked ok but I have not sealed the area between the radiator and the nostrils and quite a bit of warm air comes into the footwell area, this is pretty hard for the AC to overcome.
Also the fan does not seem to have the volume needed.
I haven't checked any of this out and will update after I have.
Dave
Also the fan does not seem to have the volume needed.
I haven't checked any of this out and will update after I have.
Dave
Henry,
Something to check.
Some cars have leaky heater core servo valves (one of the door HVAC controls allows infinite adjustment from full close to full open).
If this valve is leaking as the engine warms up hot water will flow thrugh the heater core and warm the cold air from the AC evaporator causing your symptom.
Fix is to install a shut off ball valve at the heater supply line off the intake manifold that will shut off the flow of hot water to the heater core but, be careful to open the valve during engine warm up if you don't have a water pump bypass and then shut it once the thermostat has opened.
Steve P2125
Something to check.
Some cars have leaky heater core servo valves (one of the door HVAC controls allows infinite adjustment from full close to full open).
If this valve is leaking as the engine warms up hot water will flow thrugh the heater core and warm the cold air from the AC evaporator causing your symptom.
Fix is to install a shut off ball valve at the heater supply line off the intake manifold that will shut off the flow of hot water to the heater core but, be careful to open the valve during engine warm up if you don't have a water pump bypass and then shut it once the thermostat has opened.
Steve P2125
Henry,
Forgot one thing:
If you do as I suggested above you need to insure that the door mounted control is selected to heat during engine warm up in order to open the heater servo at the heater core, if not there won't be any flow.
Select no heat position once engine warmed up and close off the ball valve from engine to heater core.
OK?
Steve
Forgot one thing:
If you do as I suggested above you need to insure that the door mounted control is selected to heat during engine warm up in order to open the heater servo at the heater core, if not there won't be any flow.
Select no heat position once engine warmed up and close off the ball valve from engine to heater core.
OK?
Steve
Richard,
Theoretically, a water pump bypass hose serves two functions: it promotes quicker warm-up on cold-start, and helps prevent water pump impellor cavitation. However I don't like them as they are another area for possible leak and make installation of the intake difficult at least for my 427FE also once the thermostat is open they allow some short cycling and they don't adress the "cold slug" issue with our rear engined cars.
There are two workarounds that should let you slide by without connecting the bypass hose. A) By means of 3 1/8" holes in the thermostat that will allow some water flow even with the thermostat closed (one 1/8" hole is not enough, OK for venting but not for flow). B)If coolant always circulates through the heater core whether the heater is on or off but, this is not the case with our cars as there is a servo valve that allows infinate control of the water from the intake manifold through the heater core so this path can be shut off if the door control is in the "no heat position" and the servo has or is shutting the valve.
Enough theory. What I do:
When I first got the car I noticed that during warm up the temp would come up to 90C (about the opening point of my 180F thermostat) then fall back to 80C then quickly rise to 120-130C or so and quickly fall back to 80C and go through this cycle a few times. What was happening was the thermostat would open then a cold slug of water from the distant radiator would enter the engine and the thermostat would close, then the engine would warm up again and repeat untill there was thermal equilibrium. Even though the temp extursions wern't really bad I didn't like the idea of any thermal shock so have developed the following cold start up proceedure:
A/C off, door heater control in "MAX HEAT" position opening the servo allowing water from the intake manifold through heater core to the radiator and back to the engine. Using this proceedure water is flowing through the radiator as it is heated in the engine, thermostat opens at 180 and stays there; there is no temp excursion or thermal shock. Once up to temp and thermostat is open I turn the door control to "min Heat" position and A/C on unless heat is wanted. So key is door heat control in "max heat"...wide open during cold start.
Steve
PS If you have installed a shut off ball valve in the heater supply line as I have to maximize A/C performance as the heater servos do leak by a little then insure it is open and after warm up when you are checking the engine compartment before taking off shut it.
Theoretically, a water pump bypass hose serves two functions: it promotes quicker warm-up on cold-start, and helps prevent water pump impellor cavitation. However I don't like them as they are another area for possible leak and make installation of the intake difficult at least for my 427FE also once the thermostat is open they allow some short cycling and they don't adress the "cold slug" issue with our rear engined cars.
There are two workarounds that should let you slide by without connecting the bypass hose. A) By means of 3 1/8" holes in the thermostat that will allow some water flow even with the thermostat closed (one 1/8" hole is not enough, OK for venting but not for flow). B)If coolant always circulates through the heater core whether the heater is on or off but, this is not the case with our cars as there is a servo valve that allows infinate control of the water from the intake manifold through the heater core so this path can be shut off if the door control is in the "no heat position" and the servo has or is shutting the valve.
Enough theory. What I do:
When I first got the car I noticed that during warm up the temp would come up to 90C (about the opening point of my 180F thermostat) then fall back to 80C then quickly rise to 120-130C or so and quickly fall back to 80C and go through this cycle a few times. What was happening was the thermostat would open then a cold slug of water from the distant radiator would enter the engine and the thermostat would close, then the engine would warm up again and repeat untill there was thermal equilibrium. Even though the temp extursions wern't really bad I didn't like the idea of any thermal shock so have developed the following cold start up proceedure:
A/C off, door heater control in "MAX HEAT" position opening the servo allowing water from the intake manifold through heater core to the radiator and back to the engine. Using this proceedure water is flowing through the radiator as it is heated in the engine, thermostat opens at 180 and stays there; there is no temp excursion or thermal shock. Once up to temp and thermostat is open I turn the door control to "min Heat" position and A/C on unless heat is wanted. So key is door heat control in "max heat"...wide open during cold start.
Steve
PS If you have installed a shut off ball valve in the heater supply line as I have to maximize A/C performance as the heater servos do leak by a little then insure it is open and after warm up when you are checking the engine compartment before taking off shut it.
Just fixed another A/C system in one of my cars - the problem was the A/C would work while driving and then, on really hot days and at idle, blow hot air. The Aux Fan was found not to be turning on (the fuse was dislodged from it's receptacle). There was a thermal switch which protect the system from overheating and this was shutting down the compressor when the car sat idle and heated up. Once going, the system cooled and worked. Not sure this applies directly to our systems, but I thought I would log it anyway.
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Update on the volume issue for my AC.
The problem I was experiencing was low volume of air from the dash vents and no air at all for the defroster.
What I found to be the problem was crushed ducting behind the dash plus the hoses for the deforster and the left hand air vent were all routed between the wiper motor and the chassis structure above the teering column.
The dash comes out pretty easily and Lance sent me some new duct hoses. I cut some 2 1/4" holes in the top of the structure (covered by the dash itself) and ran the defroster hose out there and left left lots of room for the duct hose to go around the wiper motor.
The r/h hose was crushed as well and I tweaked the hole in the structure where the hose exits the evaporator (it makes a 180 just as it leaves the evaporator and goes to the passenger side vent).
Now the defroster works and I need to turn the fan down, it has lots of volume now.
I was also able to find some more small openings to the outside that I was able to plug.
All in all a successful operation.
Dave
The problem I was experiencing was low volume of air from the dash vents and no air at all for the defroster.
What I found to be the problem was crushed ducting behind the dash plus the hoses for the deforster and the left hand air vent were all routed between the wiper motor and the chassis structure above the teering column.
The dash comes out pretty easily and Lance sent me some new duct hoses. I cut some 2 1/4" holes in the top of the structure (covered by the dash itself) and ran the defroster hose out there and left left lots of room for the duct hose to go around the wiper motor.
The r/h hose was crushed as well and I tweaked the hole in the structure where the hose exits the evaporator (it makes a 180 just as it leaves the evaporator and goes to the passenger side vent).
Now the defroster works and I need to turn the fan down, it has lots of volume now.
I was also able to find some more small openings to the outside that I was able to plug.
All in all a successful operation.
Dave
Sanden, I still remember when the Ferrari dealership asked me $2,000 for one for my Testarossa, but I got one brand new for $220 sourced somewhere else, lol.
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