Engine/Transmission (1994 - 1998) Flip on the A/C, Truck Dies.....

[Timbeaux38]

My Brother-In Law bought a 97 12v 4x4 QC LB during the winter- today he flipped on the ac for the first time running down the road- worked fine... . till he stopped. the truck died- he restarted, flipped on the ac, died again- what could be pulling the motor down to make it bog and die? any ideas????

 

[Will24]

Sounds like the compressor is seized. Tell him to take the serp belt off and try it again. If it doesn't stall, it's not an electrical gremlin and it will need compressor replacement.



-Will

 

[Timbeaux38]

he also says it will run fine if it is in drive(moving) or neutral or park, but if it is in drive and stoppeed it quits. he also says that it only runs about 150 water temp is that too low when warmed?

 

[Joe G.]

If the idle is too low it can do that. It should be at least 750 RPM in gear if it's a auto and the AC on. 800 is better. I don't think the compressor is siezed if it works fine going down the road.

 

[Will24]

Joe G, you beat me to saying about the idle speed...



My only thought was maybe the belt speed was high enough driving down the road that a tight compressor could possibly be forced into working.





-Will

 

[Timbeaux38]

Thanks for the fast repiles- now he is all worried about the water temp when warm beacuse I told him that it is bad on a 24v to idle for a long period of time and that operating temp is usually arounrd 190- he is barely @ 150 when warm...

 

[AggieJustin]

Are you sure that a 4 cyl gasser didn't get swapped in there over the winter? A friend of mine had a Ford Ranger that would do this... everytime he stopped he had to turn off the A/C or the truck would lug down and die.

 

[Will24]

The truck in question with the AC compressor is a 12valve, right?



-Will

 

[Timbeaux38]

yes it is a 97 12v

 

[Joe G.]

Thanks for the fast repiles- now he is all worried about the water temp when warm beacuse I told him that it is bad on a 24v to idle for a long period of time and that operating temp is usually arounrd 190- he is barely @ 150 when warm...

Water temp is not important. It's EGT that is. Extended idle with the EGT below 300 is not good. I use my exhaust brake to keep the EGT at about 400 if I have to let it idle for some time.