Help! Heaters not working

[musigenesis]

When I first got my bus, and up through last winter, my heaters (driver and step well - mid and rear heaters were deleted) worked fine. Sometime last summer I guess they stopped working - they blow air but the air is always cold outside air. The coil of coolant hose still coming out of the driver's side (after I did the mid and rear heater delete) use to get hot during a drive, but now it is always cold, so apparently I am getting no coolant to the heaters.

I've identified what I think are the valves on the engine that control whether coolant goes to the heaters:



This is the position they were in as of this afternoon (with the heaters not blowing hot air). Before driving to my lot tonight, I turned both of these valves to the other position (either opening or closing them, I dunno) but it had no effect - heaters still blow cold air and the coolant hose from the heater does not get hot.

Have I misidentified those valves? Is there some other valve somewhere that I also need to open? I've seen things from IC owners who say there's an additional valve down by the driver's foot, but I've never seen anything like that.

[CHEESE_WAGON]

That be them, boss...

One could still be closed. Feel the hoses on either side of each valve, or shoot them with a temp gun. If one side is cooler, the valve is closed.

If that checks out, yes, there could be another valve inside. But if there is no heat present anywhere in the hoses, they could be disconnected completely. They should tap into the engine somewhere around the water pump or thermostat area (both front of engine).

[musigenesis]

Originally Posted by CHEESE_WAGON

That be them, boss...

One could still be closed. Feel the hoses on either side of each valve, or shoot them with a temp gun. If one side is cooler, the valve is closed.

If that checks out, yes, there could be another valve inside. But if there is no heat present anywhere in the hoses, they could be disconnected completely. They should tap into the engine somewhere around the water pump or thermostat area (both front of engine).

Which position is open and which is closed with these valves? Are they closed in my pic?

[CHEESE_WAGON]

Originally Posted by musigenesis

Which position is open and which is closed with these valves? Are they closed in my pic?

No way I know to tell without disconnecting it all and watching the valve positions while moving the levers, really. It's possible the lever position indicates the valve position. i.e., lever parallel to hose = valve open?

Other than that, check temperatures on either side of the valves in either position. There could be other valves, but most will only have those two.

[CHEESE_WAGON]

I was able to find this...

Which suggests that parallel to the hose (left pic and right pic) is open (flowing), perpendicular to the hose (middle pic) is closed (not flowing). Not sure if this is a standard on all or not.

[musigenesis]

Originally Posted by CHEESE_WAGON

I was able to find this...

Which suggests that parallel to the hose (left pic and right pic) is open (flowing), perpendicular to the hose (middle pic) is closed (not flowing). Not sure if this is a standard on all or not.

Thanks for looking this up. I'll try seeing if the hose there gets hot on either side tomorrow, maybe see if I can see another valve farther upstream.

[CHEESE_WAGON]

Start by finding their source. Should be at the water pump or thermostat area on most engines. A few may tap in at the back of the cylinder head.

[Bus'n it]

In your picture, the handles are in the open position. Those valve handles when lined up with the valve body are open. When in perpendicular to valve body they are closed.. If your picture is as you left it, valves are open. After running the engine, the hoses should be warm. You may also have an optional booster pump for the heaters. If so it could be on the fritz. Follow the lines to see if you have one.

[CHEESE_WAGON]

+1 on the booster pump. Completely forgot about that.

[magnakansas]

They can be in different places...but. The last trip to the truck junk yard, the international I looked had a booster pump bolted to the firewall on the right side in the engine bay.... even had a label on it that said "booster"

electric motor was about the size of a soda can.... had the typical one inch heater hoses attached.

also, if you have an "air bubble" in the system you might not flow coolant. Most of the busses I have seen, there are one or two metal things in the heater lines that are "bleed ports" places with a little thumb screw that you can open and vent out trapped air. open this and coolant should come out... or open this and air will come out and then coolant..... or open this and you dont have enough coolant in the engine/radiator and no coolant will come out or... you have hoses/valves closed, pinched, blocked off, disconnected and no coolant will come out.

I have also seen the same kind of valves over by the drivers' left ankle in addition to valve in the engine bay. One bus I saw this summer has four valves in the engine bay, two on the right side for the right front heater/defroster. and two over by the steering shaft for the left side heaters, and another valve to the left of the driver.

william

[Maligator.]

Originally Posted by musigenesis

Thanks for looking this up. I'll try seeing if the hose there gets hot on either side tomorrow, maybe see if I can see another valve farther upstream.

I have 466e as well, mine has valve 6 inches left of my left knee when seated in drivers seat. perhaps yours is hidden somewhere over there?

[Booyah45828]

Originally Posted by Maligator.

I have 466e as well, mine has valve 6 inches left of my left knee when seated in drivers seat. perhaps yours is hidden somewhere over there?

I was just going to say that. Mine has that valve too. It's so the driver can turn coolant flow off to the heater cores when the heater isn't in use.

Trust me, in the dead of summer, you'll know if there is hot coolant in those heater cores.

Those other valves, with the handles parallel to the hose, I'd assume are open.

Like cheesewagon said, the only way to be 100% sure where they are is to remove and verify.

One thing that hasn't been asked, is the bus is getting up to 180 or so right? If coolant temp is only 100 or so, you won't get any heat from the heaters.

[cadillackid]

couple things..



others mentioned an inside valve.. my bluebird has valves under the hood and in the cab (on the driver heater) all must be open for good flow..





how did you cap off the mid / rear heater lines? if your heating system is series-flow the main line came into one heater then out another and looped-loop like that and you Capped the lines behind the last heater then you will have no flow..



if you looped the lines behind the rear heater you should get some flow..



if your system is parallel flow meaning that there are 2 lines that come into the firewall and ran the length of the bus with each heater having 2 lines coming up from the main trunk and the rear heater being at the end.. and you looped the lines with no bias (restriction) then the coolant may just loop around inside the cab but never flow through any of the heater cores..



on my carpenter bus my rear heater had a restrictor in the line to create a pressure differential (its a parallel flow system)..


my bluebird is a series system .. coolant goes in one heater and comes out then goes into the next.. if i were to remove one Id have to LOOP the hoses past it or id kill the flow if i just capped them off..

[musigenesis]

Originally Posted by Booyah45828

One thing that hasn't been asked, is the bus is getting up to 180 or so right? If coolant temp is only 100 or so, you won't get any heat from the heaters.

Yes, I know this. Even with the coolant up to 180-190, no heat at all. Got plenty of heat last winter, no heat now.

[musigenesis]

Originally Posted by cadillackid

how did you cap off the mid / rear heater lines?

I deleted the mid and rear heaters and looped the lines just behind the driver's heater. I did this almost two years ago and the looped hose always got hot when I drove and I had heat. Now the hose doesn't ever get hot and I don't have heat.

[musigenesis]

Curiouser: drove the bus to my house and lifted the hood to feel the hoses. The hose leading to the driver heater was warm up to the valve but cold beyond it, so presumably this valve is not open despite being in the open position. It is extremely difficult to turn it so perhaps it's rusted out?

The hose leading to the step well heater was warm on both sides of the valve - but the step well was still blowing cold air. Both hoses go straight into the engine and there doesn't seem to be any other valve anywhere in the vicinity.

I dunno. Last summer I took off the trim pieces around both heaters and painted them and put them back on. Is it even possible to put them back on wrongly such that it disables the heaters?

[WIbluebird]

I'm willing to bet there is air bubbles in the system. I had to add coolant to my rear engine bus after deleting the heaters.

I've driven it several times since then and the hoses running through the cabin (I am keeping the front dash heater and defroster) still get warm. The handle for shutting off my cabin coolant supply actually broke off in the open position so I'm just gonna be lazy and leave it like that for now

[CHEESE_WAGON]

Originally Posted by musigenesis

Curiouser: drove the bus to my house and lifted the hood to feel the hoses. The hose leading to the driver heater was warm up to the valve but cold beyond it, so presumably this valve is not open despite being in the open position. It is extremely difficult to turn it so perhaps it's rusted out?

The hose leading to the step well heater was warm on both sides of the valve - but the step well was still blowing cold air. Both hoses go straight into the engine and there doesn't seem to be any other valve anywhere in the vicinity.

I dunno. Last summer I took off the trim pieces around both heaters and painted them and put them back on. Is it even possible to put them back on wrongly such that it disables the heaters?

Has the coolant been flushed regularly in this bus? It's possible that corrosion or sludged coolant has clogged a valve or heater core.

[musigenesis]

Originally Posted by CHEESE_WAGON

Has the coolant been flushed regularly in this bus? It's possible that corrosion or sludged coolant has clogged a valve or heater core.

I had it flushed and replaced back in April 2019 when I first got my bus. On my last trip to the vet, er mechanic in October, they replaced the coolant filter, pressure-tested the coolant and topped off the fluid (which had gotten pretty low).

[Maligator.]

Originally Posted by musigenesis

I had it flushed and replaced back in April 2019 when I first got my bus. On my last trip to the vet, er mechanic in October, they replaced the coolant filter, pressure-tested the coolant and topped off the fluid (which had gotten pretty low).

Dying laughing at the "vet", my buses nickname "Maligator" refers to my Belgian malinois and her notorious mouth. In Tok, AK we had to get towed to the mechanic in -30 to warm up and I said the same thing "time to go to the Vet!"

Back to your thread, Ive seen those types of valves break internally in the closed, partially open and open positions. If you are having difficulty(should always turn relatively easy in this type of system, maybe just difficult to "break loose") and there is hot to the valve but cold beyond I'd suspect one of several things.

Valve is open but occluded somehow internally.
Valve is broken off in the 'closed' position.
Valve broken off partially open with an occlusion also occurring.
Something I haven't thought of that is a combination of those.

Oh and also wanted to say I was removing the heater trim pieces you were talking about last night and also my drivers console (i have a coolant leak under my console heater). I don't see anyway that you could block your system other than somehow sinking a screw right through a hose but where I couldn't say. I think our buses are probably pretty similar and I just did exactly what you did with the facial trim, I really don't think you did it that way.