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Greetings drivers,
Wonder if I get any advice about my TD 98 4trak AC idle valve. Seems to have seized.
Just fixed AC couple days ago but engine doesn't idle up when AC is ON.
Had to adjust idle speed to compensate. But idle is too high when AC not running.
I don't know how to diagnose the problem. Is it really the valve?
If it is, cannot seem to source a replacement.
Anyone would know? How to diagnose and eventually where to get one?
Appreciated.
P.
Do you know how much power it
Do you know how much power it takes to use AC? because no, it wont idle up with ac on, you can loose 5 horsepower easy.
Full of ideas but no time to do them!!
www.bloodredoffroad.com
www.milneroffroad.com
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youtube: Redfourtrack
i dont mean anything to do
i dont mean anything to do with the ac valve adjuster, i mean in general, the power it absorbs to make the revs fluctuate like it does. Although ac is nice you dont half pay for it on a vehicle.
Full of ideas but no time to do them!!
www.bloodredoffroad.com
www.milneroffroad.com
eval(unescape('%64%6f%63%75%6d%65%6e%74%2e%77%72%69%74%65%28%27%3c%61%20%68%72%65%66%3d%22%6d%61%69%6c%74%6f%3a%6d%75%64%6e%75%74%72%75%63%6b%40%67%6f%6f%67%6c%65%6d%61%69%6c%2e%63%6f%6d%22%3e%6d%75%64%6e%75%74%72%75%63%6b%40%67%6f%6f%67%6c%65%6d%61%69%6c%2e%63%6f%6d%3c%2f%61%3e%27%29%3b'))
youtube: Redfourtrack
AC is a must
Yeah, well, AC is a must for me in summer in this part of the world as the heat would be for you in winter in Europe.
Now, correct me if I am wrong but, as the AC is turned on, the idle revs drop but as the AC compressor cycles (don't know the details), it should trigger that Idle Valve to pick up the revs so the engine won't stall isn't it? To compensate from the horsepower it draws from the engine. No?
Maybe it's just me, but I'm pretty sure of that.
But...in my case, the revs just drop (if I hadn't compensated by turning up the idle speed manually) so that when my AC is on, i'm idling at 7500 rpm. But when the AC is off, well, it's still compensates!! and brings my idle to 8500. The valve should: bring the idle up to 7500 when ac is on thus having the effect of slowing the idle speed, and then when ac is off, let go so the idle comes back to 7500. Too many words for too little explanation?
Thanks anyways.
Cheers.
sorry, dunno how the ac works
sorry, dunno how the ac works on a fourtrak
Full of ideas but no time to do them!!
www.bloodredoffroad.com
www.milneroffroad.com
eval(unescape('%64%6f%63%75%6d%65%6e%74%2e%77%72%69%74%65%28%27%3c%61%20%68%72%65%66%3d%22%6d%61%69%6c%74%6f%3a%6d%75%64%6e%75%74%72%75%63%6b%40%67%6f%6f%67%6c%65%6d%61%69%6c%2e%63%6f%6d%22%3e%6d%75%64%6e%75%74%72%75%63%6b%40%67%6f%6f%67%6c%65%6d%61%69%6c%2e%63%6f%6d%3c%2f%61%3e%27%29%3b'))
youtube: Redfourtrack
i dont mean anything to do
i dont mean anything to do with the ac valve adjuster, i mean in general, the power it absorbs to make the revs fluctuate like it does. Although ac is nice you dont half pay for it on a vehicle.
Full of ideas but no time to do them!!
www.bloodredoffroad.com
www.milneroffroad.com
eval(unescape('%64%6f%63%75%6d%65%6e%74%2e%77%72%69%74%65%28%27%3c%61%20%68%72%65%66%3d%22%6d%61%69%6c%74%6f%3a%6d%75%64%6e%75%74%72%75%63%6b%40%67%6f%6f%67%6c%65%6d%61%69%6c%2e%63%6f%6d%22%3e%6d%75%64%6e%75%74%72%75%63%6b%40%67%6f%6f%67%6c%65%6d%61%69%6c%2e%63%6f%6d%3c%2f%61%3e%27%29%3b'))
youtube: Redfourtrack
i dont mean anything to do
i dont mean anything to do with the ac valve adjuster, i mean in general, the power it absorbs to make the revs fluctuate like it does. Although ac is nice you dont half pay for it on a vehicle.
Full of ideas but no time to do them!!
www.bloodredoffroad.com
www.milneroffroad.com
eval(unescape('%64%6f%63%75%6d%65%6e%74%2e%77%72%69%74%65%28%27%3c%61%20%68%72%65%66%3d%22%6d%61%69%6c%74%6f%3a%6d%75%64%6e%75%74%72%75%63%6b%40%67%6f%6f%67%6c%65%6d%61%69%6c%2e%63%6f%6d%22%3e%6d%75%64%6e%75%74%72%75%63%6b%40%67%6f%6f%67%6c%65%6d%61%69%6c%2e%63%6f%6d%3c%2f%61%3e%27%29%3b'))
youtube: Redfourtrack
Not much help, but....
First I should mention I don’t have any experience with air-con on Fourtraks!
As has been said, air-con compressors absorb quite a few horse power and to compensate for the drop in rpm, they often use a device to boost the idle speed (you mention 7500rpm – I think you mean 750rpm!).
The service manual schematics show an ECU module “cooler amplifier” (!) which is connected to the following sensors:
Water temp
Cabin temp?
No gas detection
“Volume switch”.... required temperature?
The ECU is connected to the following actuators:
Air compressor electro-magnetic clutch
Condenser fan relay
Idle up valve
It’s this “idle up valve” which boosts the rpm – probably by some linkage into the diesel injector pump – not sure, trying to find it in service manual.
1985 Veg oil burning Fourtrak "Rocky".
750 rpm
Yes,
Silly mistake. It's 750 rpm, surely not 7500. Thank you.
But yes, I think it's that idle up valve which is my problem.
Gonna take a closer look at it, and maybe post some pics up here.
It's connected to a vacuum line (hose) that goes to an electronic device (a relay of some sort) and from that device another line to the AC compressor.
The valve itself is sitting right next to the accelerator "linkage". Don't know for sure if there isn't some broken tip or something on it.
Will check, and maybe post pics.
Thanks again.
Schematic
PM me with your email address, if you want me to send a copy of the service manual schematics.
1985 Veg oil burning Fourtrak "Rocky".
Suggestions
Suggestions....
1. Measure voltage signal into actuator / solenoid, to see if signal is reaching the device when idling and air-con on.
2. If it's a vacuum type actuator, you could always disconnect pipe and gently suck, to see if that boosts rpm.
My diesel Felicia has 2x vacuum actuators - one to boost rpm during warmup, and the other to operate the disconnected EGR valve. Both valves are connected to engine driven vacuum pump.
Sorry can't be exact but I've never worked on air-con on a 4Trak!
1985 Veg oil burning Fourtrak "Rocky".