3rd Gen Tech: Colder AC in under 25
#41
#42
OK, so I'm adding a small piece to an old thread. Here goes.
1. soaked floorboards.... easiest way to tell if coolant or condensation, is it glowing green or clear?
2. for prevention of heater-core stagnation, would there really be anything wrong with cranking the ball-valve down to about 5-10% and leaving it that way?... The hot-water flow would be greatly diminished, but, there'd be enough circulation to prevent stagnation. Instead of a 14*F reduction, maybe you'd see 12 or 13, instead, but, without the worry.
1. soaked floorboards.... easiest way to tell if coolant or condensation, is it glowing green or clear?
2. for prevention of heater-core stagnation, would there really be anything wrong with cranking the ball-valve down to about 5-10% and leaving it that way?... The hot-water flow would be greatly diminished, but, there'd be enough circulation to prevent stagnation. Instead of a 14*F reduction, maybe you'd see 12 or 13, instead, but, without the worry.
#43
I'll add on to what 65stangboy and begle mentioned: why do you think they tapped the heater off the back of the head starting with the 3rd gens? And if you are seeing a 14degree drop you have blend door problem.
I did mine with a three-way valve to bypass the core and keep coolant flowing. That tends to avoid blown freeze plugs and melting #6. I tested it on long drives and never saw more than a 1-2 degree difference measured at the vent with a properly functioning blend door.
I did mine with a three-way valve to bypass the core and keep coolant flowing. That tends to avoid blown freeze plugs and melting #6. I tested it on long drives and never saw more than a 1-2 degree difference measured at the vent with a properly functioning blend door.
Last edited by NadirPoint; 05-12-2013 at 02:37 PM.
#46
Anyone know the answer to his question? Does a manual transmission need a by-pass to continue the circulation?
#47
I looked at my truck(which has a manual transmission) and it appears that the coolant supply line goes to the heater core and then runs back to the water pump. Just one single loop. I don't think cutting off the supply of coolant entering the heater core will affect anything on the engine significantly. Maybe some of the Cummins Diesel Experts who know more about the manual trucks and cutting off the supply of coolant would comment.
#48
Well I did the mod, and it turned out great. The only thing I did different was I found a 3/4" valve with 3/4" barbed ends (all one piece). I let the truck sit for awhile then went out there cut the hose, put on the hose clamps, and put the valve in. Worked like a charm. The valve cost me about $7.50 at Lowes. It took longer to wait for the truck to cool down enough than it did to put the valve in. I saw a 14* drop in temp coming out of the vent.
Thanks Wildcat
Thanks Wildcat
#49
Mine looks like the pictures below. You can get this heater shut off valve at Oriley's for $10 and change. Tell them to look it up for a 1971 Dodge D100 truck! Anyway, Oriley's heater shut off valve is made by Murry and is American made.
My Truck is a manual NV5600 transmission and the return line from the heater core goes towards the engine and then to the water pump. I don't think cutting off the flow to the heater core will hurt the engine.
My Truck is a manual NV5600 transmission and the return line from the heater core goes towards the engine and then to the water pump. I don't think cutting off the flow to the heater core will hurt the engine.