4020 cab heater

[Fixingfarmer]

The heater supply connection made on the thermostat manifold . Would be better
On the engine side of the stats vs the radiator side of the stats.
More pressure thus more flow . Plus there
would be some heat as the engine is warming up .

I believe the connection in the pipe is on the radiator side immediately 1/4 inch above the stats so radiator side and cold till thermostat opens.

Explains why I’ve seen some creative plumbing at that drain plug in the block

 

[Tx Jim]

Removing hood isn't that difficult on 4020 tractor with a mounted aftermarket cab. Cab has a removal filler plate over rear of hood Remove a bolt on each side rear of hood then release spring loaded latch in front of radiator then raise hood. BTDT several times. .

I still think JD engineers thought cab heater coolant hoses should be attached at water pump via a hose barb on thermostat by pass line & front of cylinder head very similar to 4020 parts photo.

Many yrs ago I sold/mounted new Year-A-Round & Hiniker cabs but never attached heater due to being in Texas & not needing a cab heater in Tx Winter. In majority of most Texas winters one will have AC on low after tractor has reached operating temperature when operating most cab tractors.

 

[buickanddeere]

I believe the connection in the pipe is on the radiator side immediately 1/4 inch above the stats so radiator side and cold till thermostat opens.

Explains why I’ve seen some creative plumbing at that drain plug in the block

This is where a coolant port plug in the head would be used . No place to rout out of the block .

 

[Glen D Anderson]

FWIW returning the heater core flow into the thermostat bypass line as done by the OEM(at least on Hinson cab equipped 4020s) was not one of their better ideas.

While the port is technically connected to the suction side of the water pump, the flow going through that line is substantial until the thermostats have almost opened completely making it difficult for the flow from the heater core to overcome.

IMO, the heater core return needs a dedicated port on the suction side of the water pump. Then your choice of where to connect the heater core supply(top left of the cylinder head, any of the plugs on the right side of the cylinder head, or even the block) is just splitting hairs.....

 

[Tx Jim]

I find it odd what you stated due to JD engineers utilized at same heater hose attachment to engine on tractors up through 1972. I guess JD engineers were slow to change.

https://partscatalog.deere.com/jdrc/sidebyside/equipment/8480/referrer/navigation/pgId/8308861

 

[Fixingfarmer]

I find it odd what you stated due to JD engineers utilized at same heater hose attachment to engine on tractors up through 1972. I guess JD engineers were slow to change.

https://partscatalog.deere.com/jdrc/sidebyside/equipment/8480/referrer/navigation/pgId/8308861

They did leave something to be desired Grandpa had to have an additional electric heater in his doing the snowfighter stuff for businesses up here he was glad to have the bigger batteries he added and an alternator.

Heats about as well as that dodge 5500 service truck I had won’t really thaw out your toes without some help

 

[JeffinAB]

Maybe you need a second ball valve. I'm thinking just above the tank heater but before the tee connector. Then turn it closed when engine running, that eliminates any flow following the path of least resistance through the tank heater circuit. Maybe that will help force the coolant up to the cab

 

[buickanddeere]

The tank type convection heater . Is plumbed all on its own on the left diff of the engine . Between the block drain and any coolant plug on the left side of the head .
Regarding the heater plumbing . Warmed coolant should not have to travel down hill . Cold coolant should not have to travel uphill .

 

[Glen D Anderson]

The tank type convection heater . Is plumbed all on its own on the left diff of the engine . Between the block drain and any coolant plug on the left side of the head .
Regarding the heater plumbing . Warmed coolant should not have to travel down hill . Cold coolant should not have to travel uphill .

After lowering & replumbing the heaters properly on our 3020 & early 4020, the difference was huge.

In the past, the heaters would get scorching hot with very little heat being transferred into the head & block. Now you can almost hold your hand on the heater indefinitely after it's been plugged in for a couple of hours. Proper convection is now happening & the heat is making it into the places it's supposed to.

 

[Tx Jim]

I determined yesterday via Facebook that after the OP removed the "Y" in the hose plumbing as he was advised to do 5 or 6 days ago on this site & Green Tractor Talk that his tractors cab heater began to put out heated air.