[kevlar]

For the likes of me, I can not get coolant to flow through the heater core. We changed the thermostats a couple years ago as the tractor was always running cold (by the gauge) and ever since we have little to no heat. I can't remember if the heat was getting poor and if that was part of the reason for changing the thermostats? (Bad memory, I know!) We changed the heater hoses as I thought maybe there was a collapsed hose, didn't help. Can't remember exactly when we changed it but know it ran last winter with little heat, but mostly just use it for pushing snow and there was no snow last year so only had it going a couple times. Sometimes it would have some heat if it was wound up, but at idle it cools off instantly. So this winter I removed the thermostats again to check them out, they are installed correctly and open at the right temps. I put a tap on one hose so we could pressurize the system to get coolant flowing through the core. Have loosened the hoses at the core to try get any air out, coolant runs out.

Which way should the coolant flow? I would think it should go from the hose that is connected right to the top of the pump, but if I remove the hose that is connected to the thermostat housing, little to no coolant comes out. I rigged it so we could remove the hose from the pump, and it flowed some, but only maybe half capacity of the hose or even less, but to me this seems backwards. Ran it again and have some heat, but again as soon as it goes to idle, the heat stops instantly. I took the front cover off the pump and it's not broken and turns with the engine, is it possible for the pump to wear enough that it wouldn't push the coolant up to the top of the cab but still cool the engine? Have tried everything to bleed out any air, but can't seem to get it to circulate. No the AC isn't running and the coolant is topped up. If it is air locked, what's the trick to get it out? Where the hoses connect to the core aren't easy to get to and can't connect a hose up there to pour coolant in there to get the air out. The flow control also works, so I know it opens up.

Any ideas?

 

[albertabuck]

Sounds like you are getting an airlock. Often when you only get heat in the cab under high engine speed when it is hot, it is because you have air in the lines going up into the roof. One of the biggest causes of this is a leaking head gasket letting gases into the cooling system. When you work the tractor, do you ever notice you are losing antifreeze? Even at lower speed and cooler temps, a blown head gasket will often cause coolant to get blown out of the rad.
Belive it or not, but losing heat in my 4850 is always the first sign the gasket is letting go. Those are known for that issue, and thats the first sign, second one is when you are constantly losing a bit of antifreeze while everything seems normal, and the third is when all hell breaks loose between two holes and she dumps half the coolant on the ground. Then you know its time to get reaquainted with it again lol.

In my experiece with other brands in the older models, IH, MF and others, once you have good circulation into the roof and then lose it afterwards, either you have a leak or it is getting air into the system. If I worked on someones tractor, either I would do it or tell them too when they got it home, and that was get it hot and run it wide open for several minutes to make sure the heater was completely purged of air. Something like on a mix mill or pulling a highboy load of bales is about some of the best loads I use in winter to do it.

 

[MF cowboy]

You used the correct thermostat with the lower disc?
That whole heat selector knob and cable and valve is a Mickey Mouse set up.
Barring any issues with the control maybe the core is plugged?

 

[MF cowboy]

Reason I mention that control valve is this 8160 I have sitting here the control never did completely shut off.
Always lets heat through and fights with the a/c.

 

[AnviL]

Try reversing the lines to the core... if it's a bit plugged up that may help clear it out.
Also I believe the coolant flows from the head where it's the hottest to the pump.
If understand I think you were under the impression the coolant flowed from the pump to the head?

 

[kevlar]

Sounds like you are getting an airlock. Often when you only get heat in the cab under high engine speed when it is hot, it is because you have air in the lines going up into the roof. One of the biggest causes of this is a leaking head gasket letting gases into the cooling system. When you work the tractor, do you ever notice you are losing antifreeze? Even at lower speed and cooler temps, a blown head gasket will often cause coolant to get blown out of the rad.
Belive it or not, but losing heat in my 4850 is always the first sign the gasket is letting go. Those are known for that issue, and thats the first sign, second one is when you are constantly losing a bit of antifreeze while everything seems normal, and the third is when all hell breaks loose between two holes and she dumps half the coolant on the ground. Then you know its time to get reaquainted with it again lol.

In my experiece with other brands in the older models, IH, MF and others, once you have good circulation into the roof and then lose it afterwards, either you have a leak or it is getting air into the system. If I worked on someones tractor, either I would do it or tell them too when they got it home, and that was get it hot and run it wide open for several minutes to make sure the heater was completely purged of air. Something like on a mix mill or pulling a highboy load of bales is about some of the best loads I use in winter to do it.

My mind was wandering to a leaking head gasket also but think I am trying to convince myself otherwise! The tractor gets a fair bit of use in the summer months running vacs and picking stones and grain dryer, so you would think eventually the air would get worked out of it. It was low once this fall when we got done drying I checked it and is was down about a half gallon, but honestly don't know when it was checked last.

You used the correct thermostat with the lower disc?
That whole heat selector knob and cable and valve is a Mickey Mouse set up.
Barring any issues with the control maybe the core is plugged? View attachment 158072

Yes those are the thermostats I put in it, and they are sitting in the block with the disk towards the engine side. The core seems clean, I have taken the lines off and blown through them and there is no restriction.

Try reversing the lines to the core... if it's a bit plugged up that may help clear it out.
Also I believe the coolant flows from the head where it's the hottest to the pump.
If understand I think you were under the impression the coolant flowed from the pump to the head?

So you believe it flows from the thermostat housing around to the pump? I'm thinking now you might be right, but at first thought I would think it would come from the pressure side of the pump around to the thermostat, but I don't think so now. Just seems backwards to me, but I have been wrong before!

I think I will try a few different ideas to get the air lock out before ripping the head off. Just getting tired of making a mess with antifreeze everywhere trying to solve this.
Won't get to it today, have a fun day ahead of getting the books done up for the year!

 

[albertabuck]

Before you do anything, make sure your rad cap is good, you wouldn't believe how something that simple can cause issues lol.
As for coolant flow, it like electricity takes path of least resistance. Normally supply for a heater comes from the output or very close to it of the water pump. For example, many Deere have a outlet right off the pump for this, was also a very common setup with automotive in days past as well. But then depending on how the flow bypassed the thermostat, then you can see the heater being supplied from other points. For example an 855 Cummins it comes off the front of the water rail above the heads, and returns down by the oil cooler port. This is so you get circulation while thermostats are closed.

This thing doesn't have a circulating block heater or such bred into a heater hose or anything does it? So many have no idea how improperly installing one of those can end up effecting flow by theoretically creating a bypass situation.

Also I have seen where replacing factory molded hoses with standard stock can cause issues with the hose pinching off where there is a sharp bend.

As for if your heater core is restricted, can you huff and puff and blow thru it? Careful using pressure, most heater cores are lighter construction than rads.

Also I have seen where an older heater core developed a pin holes which would allow air to enter but didn't actually leak coolant. Even a half loose hose clamp in the roof can allow air to leak in but will hold coolant. Either will allow the coolant to drain back down and recreate an air lock each time.

I used to have a book on those Masseys but thats one that got borrowed and never come back home, that has that newer style Perkins in it right? Quantum or something they called it?

 

[MF cowboy]

Yeah I'm with buck on that rad cap.
Give that a very close check out.
Quadram engine or 1000 series now obsolete also.
Updated and squared up version of the 354.4.
Each cyl had 1Litre capacity.

 

[kevlar]

The rad caps good, have tried a few different ones. There is no circulating heater. Had a funny experience whith one when I put one in our grain truck. Tied it into the heater hoses and the first time I used it it just circulated through the heater! Cab was warm but the engine was ice cold! Put a valve in the line to stop that from happening again. Can blow through the core by mouth easily. Was thinking of checking all the hose clamps again as I was thinking about them letting air in like albertabuck mentioned. It has a Perkins, if it's the newer style, I don't know. I will try to get some pics tomorrow of how the hoses are hooked to the engine to see what you all think. Maybe it will be warm enough this winter this won't be an issue anyway! Ya right.

 

[MF cowboy]

I'm wondering if there is a possible air leak up in the top from the heater core?
I'm trying to remember here is that heater control valve not joined to the core with some plastic fitting with 2 bolts with a gasket or something?

 

[kevlar]

I'm wondering if there is a possible air leak up in the top from the heater core?
I'm trying to remember here is that heater control valve not joined to the core with some plastic fitting with 2 bolts with a gasket or something?

Yes it's joined with a plastic elbow with a rubber gasket, gasket seems good yet. Will get a picture of that too.

 

[kevlar]

Well after ripping this stupid thing apart many times and trying everything, I might actually have heat now. Tried everything to get the air out, bled it from the top, unhooked the lines at the engine, oh by the way, it does circulate from the hose coming out from the thermostat housing and returns to the top of the water pump. We removed the pump and couldn't see in it and it's all pressed together so left it alone, but a mechanic said it's very unlikely to be the pump. Put it back on and removed the heater core, flushed it out, it wasn't bad only a little bit murky. Tried it and still nothing.My brother followed all the lines to make sure nothing pinched, all good. So by now we're getting fairly pi$$ed off at this thing, so thought try unhooking the return line at the motor and pressurizing the system to get coolant flowing, we had tried this before and only could get a trickle, same thing with it running, very little flow. Pushed through a couple pails full of coolant and it wasn't improving, so now getting more angry I gave it a good blast with air at the rad (I know I shouldn't do this!!) and held it for a few seconds, and finally it gave out a big gulp of coolant! Not 100% sure but think the air lock was in the return line under the cab instead of up in the core where it normally would be. That's the only reason I can think of why we couldn't get the air out at the top. The lines go under the cab then come back up to the engine and I think that's where the air was. Now we can finally get working on something else!

 

[MF cowboy]

Hmmm.
Either air or possible blockage.
The only place I could think of possible blockage is if some of the heater hose got skived or something at the joint coupler where the heater hose goes up the cab post.

 

[kevlar]

Ya I don't know, seemed strange but it worked. We had changed all the hoses a couple years ago because we thought a hose might have collapsed, everything looked and felt good the other day. Will find out for sure if it's permanently fixed in a day or two, waiting for a new cutting edge for the blade before we can push this last snow.