CDLong Posted January 28 Share Posted January 28 My next issue is heater air flow. After installing the refurb engine temp gauge from Blue Truck Parts, engine is at operating temperature. I can tell inside the cab is getting warm. I have air flow in defrost mode, (enough I can feel the flow), but don't seem to have any air flow in mix or floor mode. The fan is noisy off and on while it's in operation. The engine does not have an AC compressor on it. If I remember correctly, I had air flow in vent mode when I purchased the truck and drove it home. It was hot that morning and I had the vent windows all the way open & the heater in vent mode for air movement because the AC didn't work. I will attempt to drive the truck with another person to see of any air flows while it's moving. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted January 28 Share Posted January 28 We have a number of current threads going on this, and Gary is documenting his testing and improvements. If you have a vacuum leak the climate controls will default to defrost. A noisy fan usually means the bearings are worn or the grease has packed up. Some people have drilled a hole in the bushing to add oil but the usual solution is to replace it for around $30 (that's what I did) Link to comment Share on other sites More sharing options...
CDLong Posted January 28 Author Share Posted January 28 We have a number of current threads going on this, and Gary is documenting his testing and improvements. If you have a vacuum leak the climate controls will default to defrost. A noisy fan usually means the bearings are worn or the grease has packed up. Some people have drilled a hole in the bushing to add oil but the usual solution is to replace it for around $30 (that's what I did) Yeah, I searched here and the net before I posted but didn't find anything specific to my issue. Thanks for Gary's testing. Once it stops raining, I can follow Gary's lead. When the controls are placed in mix or floor, I have no air flow thru the defroster vents. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted January 28 Share Posted January 28 We have a number of current threads going on this, and Gary is documenting his testing and improvements. If you have a vacuum leak the climate controls will default to defrost. A noisy fan usually means the bearings are worn or the grease has packed up. Some people have drilled a hole in the bushing to add oil but the usual solution is to replace it for around $30 (that's what I did) Yeah, I searched here and the net before I posted but didn't find anything specific to my issue. Thanks for Gary's testing. Once it stops raining, I can follow Gary's lead. When the controls are placed in mix or floor, I have no air flow thru the defroster vents. Well, the "only have defrost" is a well known and documented issue. Also if you don't have vacuum, the fresh air door by the passenger hood hinge won't close. Look at the 3 port manifold on the center firewall/cowl just below the hood gasket. Follow this into the cab. Follow the tube from the vacuum motor on the plenum by the hinge. If you find broken hard plastic lines splice them with a piece of rubber vacuum tube or tygon fuel line intended for small (weedwacker/blower) engines. This is easily found in any big box outdoor equipment aisle with the replacement sparkplugs and pull cords. If you have a 'juice can' vacuum reservoir on the passenger inner fender, take it off and see if condensation has rusted a hole in the bottom. The diverter door in the ductwork is known to come off/break it's hinge. A member here (Chuske) makes a kit to fix this. There's a thread and a link in the marketplace to that issue. These are the most obvious things I can think of, off the top of my head. Link to comment Share on other sites More sharing options...
CDLong Posted February 1 Author Share Posted February 1 Well, the "only have defrost" is a well known and documented issue. Also if you don't have vacuum, the fresh air door by the passenger hood hinge won't close. Look at the 3 port manifold on the center firewall/cowl just below the hood gasket. Follow this into the cab. Follow the tube from the vacuum motor on the plenum by the hinge. If you find broken hard plastic lines splice them with a piece of rubber vacuum tube or tygon fuel line intended for small (weedwacker/blower) engines. This is easily found in any big box outdoor equipment aisle with the replacement sparkplugs and pull cords. If you have a 'juice can' vacuum reservoir on the passenger inner fender, take it off and see if condensation has rusted a hole in the bottom. The diverter door in the ductwork is known to come off/break it's hinge. A member here (Chuske) makes a kit to fix this. There's a thread and a link in the marketplace to that issue. These are the most obvious things I can think of, off the top of my head. Removed the center panel cover, the radio, and glove box. All the vac pots can be operated by hand. Removed screws from heater controls and moved controls backwards. While fishing, I found the bottom lever, does not have a cable hooked to it to tell the pots what to do? Gotta do some fishing for the cable after I search for cable diagrams. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted February 1 Share Posted February 1 Well, the "only have defrost" is a well known and documented issue. Also if you don't have vacuum, the fresh air door by the passenger hood hinge won't close. Look at the 3 port manifold on the center firewall/cowl just below the hood gasket. Follow this into the cab. Follow the tube from the vacuum motor on the plenum by the hinge. If you find broken hard plastic lines splice them with a piece of rubber vacuum tube or tygon fuel line intended for small (weedwacker/blower) engines. This is easily found in any big box outdoor equipment aisle with the replacement sparkplugs and pull cords. If you have a 'juice can' vacuum reservoir on the passenger inner fender, take it off and see if condensation has rusted a hole in the bottom. The diverter door in the ductwork is known to come off/break it's hinge. A member here (Chuske) makes a kit to fix this. There's a thread and a link in the marketplace to that issue. These are the most obvious things I can think of, off the top of my head. Removed the center panel cover, the radio, and glove box. All the vac pots can be operated by hand. Removed screws from heater controls and moved controls backwards. While fishing, I found the bottom lever, does not have a cable hooked to it to tell the pots what to do? Gotta do some fishing for the cable after I search for cable diagrams. The cable (wire*) should go to the heater box behind the glove compartment Link to comment Share on other sites More sharing options...
CDLong Posted February 1 Author Share Posted February 1 The cable (wire*) should go to the heater box behind the glove compartment The only cable connection I can see is on top of the heater box. It moves when I change from AC to heat. I can't see or feel where another cable would connect? I was able to get a photo of where the cable attaches to the heater controls. Link to comment Share on other sites More sharing options...
mat in tn Posted February 2 Share Posted February 2 The cable (wire*) should go to the heater box behind the glove compartment The only cable connection I can see is on top of the heater box. It moves when I change from AC to heat. I can't see or feel where another cable would connect? I was able to get a photo of where the cable attaches to the heater controls. if your truck is a factory air truck then I don't think that one gets a cable. the vacuum selector switch supersedes it and operates the damper servos instead. Link to comment Share on other sites More sharing options...
Gary Lewis Posted February 2 Share Posted February 2 if your truck is a factory air truck then I don't think that one gets a cable. the vacuum selector switch supersedes it and operates the damper servos instead. Right. The EVTM has a bit of an explanation: https://www.garysgaragemahal.com/ac-heater.html Link to comment Share on other sites More sharing options...
CDLong Posted February 2 Author Share Posted February 2 Well, the "only have defrost" is a well known and documented issue. Also if you don't have vacuum, the fresh air door by the passenger hood hinge won't close. Look at the 3 port manifold on the center firewall/cowl just below the hood gasket. Follow this into the cab. Follow the tube from the vacuum motor on the plenum by the hinge. If you find broken hard plastic lines splice them with a piece of rubber vacuum tube or tygon fuel line intended for small (weedwacker/blower) engines. This is easily found in any big box outdoor equipment aisle with the replacement sparkplugs and pull cords. If you have a 'juice can' vacuum reservoir on the passenger inner fender, take it off and see if condensation has rusted a hole in the bottom. The diverter door in the ductwork is known to come off/break it's hinge. A member here (Chuske) makes a kit to fix this. There's a thread and a link in the marketplace to that issue. These are the most obvious things I can think of, off the top of my head. Removed the center panel cover, the radio, and glove box. All the vac pots can be operated by hand. Removed screws from heater controls and moved controls backwards. While fishing, I found the bottom lever, does not have a cable hooked to it to tell the pots what to do? Gotta do some fishing for the cable after I search for cable diagrams. https://forum.garysgaragemahal.com/file/n145755/Missing_heater_cable.jpg Also if you don't have vacuum, the fresh air door by the passenger hood hinge won't close. The door works correctly. Link to comment Share on other sites More sharing options...
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