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Heat?

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BoneIdle

BoneIdle

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Well, this is odd:

The GT is running great and the new clutch is working well, but I seem to have very little heat.

I get cold air until the thing has been running well into the normal range. Considering the temp was about 13 degrees here today, I'd kind of like a little bit quicker warm up.

So, a couple of questions. The two vents in the center of the dash... can they be completely closed?

I do have the fresh air lever below the dash pushed forward all the way, so that's sealed off.

Is there a recommended method for using the heater?

I also noticed that the heater fan squealed for about 30 seconds when I first turned it on. Should I be worried about that?

On a related topic, how much sand should I put in the rear compartment to increase traction on snow?
 
GT is 300 pounds heavier than a roadster. With proper tires you should have sufficient grip back there.

Heater valve opening all the way?

It may be that there's a bunch of err.... "fur" in the heater matrix, too. Usually that thing should toast you outta th' car. Make sure the selector knob for "Defrost" and "Interior" is flipping the deflector, too.

Another possibility is hardened/rotted foam seals on the "flapper".

Mirrors and a small flashlight can help inspect the guts without pulling all taht stuf apart.... That can be a real contortionists nightmare.
 
As far as traction goes; I don't run any weight in the `80 roadster...and just some half decent all seasons...Does better than any rwd american car I've driven in the snow, I guess it's just much more balanced and easier to control.
 
Roadster was (is) 48/52, IIRC. GT has more tail weight. Good tires make it a non-issue. We've driven both thru every imaginable condition (in the north-eastern US) and had few issues. I kept chains in the boot of the roadster and only put 'em on once, and that was as a token attempt when "black ice" was present under snow. I'd say it didn't change things a bit.... We made destination and woulda done so either way.

The things are akin to goats. Really!
 
BoneIdle said:
Is there a recommended method for using the heater?
Click to expand...

MG's have heat?
 
Terri;

You know these cars are "HOT"
Of course they have heat.

Dave :devilgrin:
 
Since I never drive mine unless the top is down....I have never even turned that little knob. I don't remember even hooking it up. Hmmmm, another thing to check.
 
Cover the fresh air grill infront of the windshield with tape or the magnetic cover moss sells. Yes it will stay on to 90+mph. Then open up the the fresh air vent. The heater will then pull the already warmed air from the cabin and reheat it. Works wonders when it's really cold like -15f with the top up. Also cardboard infront of the radiator helps a ton. Cover up the bottom 1/3rd or so to start and see if that helps.
 
Doug: Snow is what we didn't have in Florida, had too much of in Iowa, and still have more than I like here in Indiana :smile:)

On further examination, the traction really isn't an issue. I think that driving an S-10 with 500 lbs of sand in the bed for the past two winters skewed my perspective a bit.

I will start with burping the system, move on to the flappers and install some tape over the air intake.

I'll also double check the heater control valve. I was moving, but there's the possibility that it's not opening completely, especially since the engine had been removed and reinstalled.

I'm thankful that I have a well sealed garage and a decent space heater. That should keep the frostbite away while doing the non-running portion of the diagnostics, and with any luck, the outside activities will be graced with free-flowing hot air running through the interior of the car.

Oh! Related question: What's the correct position for the rocker switch that operates the rear window defroster?
 
Garry said:
Oh! Related question: What's the correct position for the rocker switch that operates the rear window defroster?
Click to expand...

Of this device I have no knowledge. Much too "modern" fer me. :wink:
 
Heater valves have been known to move with the cable, but have the inlet port clogged solid with junk...not allowing fluid to flow to the heater matrix. You may need to remove the two fixing screws and clean out the inlet port.
Cheers,
D.
 
My thought on the valve too. Even though the arm is moving, the valve itself might not be opening properly or even all the way.
 
ISTR we had a leak at that valve when it was here. I think Garry changed it back in Iowa?
 
UPDATE:

Well, Doc and I talked, and I'll share the latest developments here, as well.

I am getting warm air, but only on the passenger side of the car. I found that out during when I was flailing around desperately wishing for heat. My right hand came to rest on the defrost vent on that side and there it was...

Comments, ideas, questions are welcome.
 
Stewart.

It took me a couple of hours to get that. Rear Heater Demodulator, Rubber Heating Device, Radical Heat Dampener, were only a few of the interpretations I came up with before realizing that RHD = Right Hand Drive.

LOL

...Still, it might be worth considering. hmmmm.
 
It may be worth your time to redo the hoses for the defroster. It's not a horrible job to do. I dont know if your year had the tube and elbow adapters for the heater 635-520 and 363-110 for the tubes. I added these to my 73 and made a huge leap in preformance and opened up some more room behind the radio. Also try putting a block of foam in the passenger side floor vent and see if the flow changes to the drivers side.

Worse case buy a 12 volt electric blanket and put it in your lap when cold. Works wonders in a roadster in 30 degree weather with the top down at 75mph and should do just fine in a gt. https://www.amazon.com/Roadpro-12-Volt-Fl...1776&sr=8-1
 
New here, but this info on heater valves has been recently added to this site: https://www.britishcarforum.com/bobmuenchausen/12245.html There are two pages - this one on OE valves and a second on alternative valve possibilities - there are many, limited mostly by your imagination. Also, there is another site, https://www.mgb-stuff.org.uk where, if you go to "Spanners" click and then click on heater at the top of the next page, Paul Hunt has a good set of discussions that cover more than just heater valves. FYI.
 
Hey Bob!
I see you moved to Oregon! Welcome home.
Always good to see you. How many times has it been? AMGBA '89, MG2001, ABFM a couple of times. Maybe more, always a pleasure!
Keep that B GT running.
C Ya,
Mark
 
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