No heat

[Gliderman8]

I recently completed the resto of my TR6... now it just sits hibernating through the long cold winter. I just started it up and let it run to operating temp.
The problem is that I do not have any heat in the cabin. After it got up to operating temp. I pulled the cable to open the water valve then went and felt the top hose going into the heater core.... it was stone cold. Right now I suspect that the water valve is not working (it was replaced with a new one when I did the engine).
So, my question is what is the best way to test the valve?
My thought was to undo the top hose at the firewall connector and then slowly open the water valve.
Is this the correct way? Is there a better way?
Baby it's cold outside.... and in!

 

[DNK]

hopefully it's the valve because if not you got no coolant in the head.
Yikes

 

[TR3driver]

Nah, could be a blocked heater core, or one of the lines. Both are common on TR3s, not sure about TR6.

 

[BobbyD]

As Randall said, it sounds like a blockage in the heater core. Did you have heat before your put it up for the winter? You can always pull both heater hoses off of the engine/heater valve and see if you can blow through the hose. I'd hesitate to use compressed air in case there is a major blockage and you end up blowing out the heater core. I've never done it but I'd think lung power would be enough to circulate the water through the core. If it ends up being a bad heater control valve, here's an option that works a whole lot better. I put it in back in the fall and it works great.

 

[DNK]

He says his hose is cold.Would some residual heat be there?

 

[TR3driver]

I've never done it but I'd think lung power would be enough to circulate the water through the core.

I've done it, works. Of course it pays to think about where that water is going to go, as I've also gotten a surprise doing it.

But on a Stag without AC (as LE1473L was originally), the heater valve is inside the cabin so blowing as much coolant out as possible is a good starting point when the valve needs service.

Thanks for the valve P/N, Bob, I'll squirrel that away for future reference. Looks like it would also be a good option for TR3 owners that want to add a remote control valve.

 

[TR3driver]

He says his hose is cold.Would some residual heat be there?

Lack of circulation is lack of circulation; doesn't much matter where the blockage is. The hose will eventually warm up some, but it takes a lot longer than the rest of the engine and will always be noticeably cooler IMO.

Went through this with a non-LBC last year; after two trips to the radiator shop I dug into the shop manuals myself and learned that model has a restriction to limit pressure to the heater core. On the third visit, they flushed the restriction and found it full of silicone sealant from a poorly done water pump change. The place that did the water pump no longer gets my business (but I had already decided that before discovering the silicone, as they screwed up several other things as well).

 

[Gliderman8]

Don-
If I had coolant in the head wouldn't it show up in the oil? The dipstick is clean.
As for heat before the rebuild.... I never had the engine running until after the rebuild so I can't say; although I did flush the heater core prior to reassembly.
So, if I open the heater valve with the hose removed will that tell me if the valve is working?
Bob- if it turns out to be the heater valve, I will check into that alternate setup... thanks!

 

[BobbyD]

The failure of the heater valve is typically a ruptured diaphragm and the whole thing leaks. I haven't heard of them just not opening (unless the cable is slipping) though I'm sure that could happen. The heater valve lever is fully opening and closing isn't it? Don't go by the knob position in the car, go by the movement at the valve itself.

Personally I'd first pull the heater valve hose and the heater return hose to the engine and make sure that you have circulation through the heater. Take a deep breath and blow! Try it in both directions. Opening the valve without the hose attached and running the engine will spit coolant everywhere if the valve is good. I guess you could always pull the heater valve right off the engine and test it in the kitchen sink. Water should flow easily through it.

 

[angelfj1]

G-man: just take it logically. You say you have the engine up to operation temp. Do you have access to an infrared thermometer? if you do, I'd like to know the temp of the fitting connecting the valve to the cyl head and then the temp of the hose leaving the valxe and going to the heater.

 

[AltaKnight]

Don-
although I did flush the heater core prior to reassembly.

Well, in the Great White North where I live, the first thing I would think about is that the water(?) you flushed the core with is now a solid block of ice in the heater coils?
Just a thought!

 

[Gliderman8]

NO, no leaks. I will try pulling the hoses leading to the heater core and blowing, but I'm betting they are open. If they are, then onto the heater valve itself.

Angelfj- no infared thermo but "taking it logically" is good advice. One thing at a time.
If I get some time this evening, I will head out to the great North Pole or better known as my garage.

 

[Gliderman8]

Graham-
I can assure you there is antifreeze flowing through my TR6's lines....

 

[Gliderman8]

I guess you could always pull the heater valve right off the engine and test it in the kitchen sink. Water should flow easily through it.

Update
Bob- I did just what you suggested.... pulled the heater valve and ran water through it in the sink. It worked just fine both in the open and closed position. Can't do it tonight, but tomorrow I will remove the hoses going to the heater core and blow into them

 

[mallard]

If you just did some work on the cooling system for your car make sure that the system has been topped off. Just filling to the top of the radiator will not top off the system. You also must have fluid in your overflow bottle so the car can suck up the needed fluid to pressurize the system. The Radiator cap is lower that the thermostat so you must let the car heat up a couple times so it can pull the fluid out of the overflow to fill the system and get the air out. You will have poor heating and cooling if you have air in the system.

Keith

 

[Gliderman8]

Don-
Sorry, I misread your post.... I pulled the heater valve off and yes, there is coolant in the riser pipe coming from the engine.
I need to slow down and read more carefully!

 

[PAUL161]

Elliot, Just an idea that stems from a 32 Chevy I restored once. I couldn't get hot water to go through the heater core. Found out it was air bound. Evidently this was a common occurrence back then as the manufacturers put an air bleed valve on some of the heaters to solve this problem. Cracking a heater hose connection down stream works sometimes also. Trying to help cover all the bases.

 

[DNK]

What Mallard said is kind of the same as Paul's idea. make sure it is full and air free.
Lucky it's not a TR8 ,they're a bare to burp!

 

[Gliderman8]

I now have heat in the cabin.... After I established that the valve was indeed working (thank you Bob) I then blew through the heater core hose to make sure there was not blockage.
What fixed it?
You all guessed it..... as Don said I "just need to burp it"
I remove a hose while it was running and it must have evacuated any air cause now it works.
OK, so now that it works they expect more snow and ice tonight which means by the time the weather cooperates I won't need the heat anyway!
to everyone for their wonderful help.... it's appreciated!

P.S. I think I will order that alternate water valve anyway Bob.

 

[DNK]

Can't take credit. Just reiterated what someone else said.
Unless I act like a real boss and take credit for others ideas.