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MGB Heater Box Removal

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Lynn Kirkpatrick

Lynn Kirkpatrick

Jedi Hopeful
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I've read the posts about how the heater box is a pita to remove. I want to be sure I don't bend something that will cause "issues". (why don't we say problems any more?)

How many screws hold the box in place? I removed the big one at the top that goes into the firewall, and a rusty one on the left end, near the throttle cable. When I pry the box lifts a little and the top of the box tilts toward the front. I hear some crunchy noises, as if old dry gaskets are giving way.

There is a tray that runs along the bottom front of the box that holds the windshield washer hose, the blower wires, a brake line, and maybe the clutch line. Under all of that are 2 screws. In the attached pic the screwdriver pointing to one of them.

Are they holding the box down?

I have also pulled the defrost tubes out. Does the box pull straight up, once free?

Thanks for the help.
 
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Well, now the picture is attached.
 

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There should be a screw on each side and three across the front (if memory serves). The tab on the top with the one to the firewall. It should come away with those all removed. The circular gasket sealing the blower outlet to the firewall can be a bear. The control cable inside the lower part (under dash) needs to be disconnected as well. Then it should come straight out.
 
When you put it back, use new rubbers (Moss), allow for plenty of time. Lubricate the rubber with a non destructive lubricant, such as silicon and have patience. Removing the heater is easy, you'll realize that when you start to put it back in. Reconnecting the cable in the box is a bear, you need to be a contortionist! You might add a few new words to the English language, but that's normal, don't fret! If I had a choice, I'd rather change a transmission! :livid: PJ
 
A dexterous 12-year-old would be handy to have around for the cable reconnection. :devilgrin:
 
I've the box out. It took some fiddling to get past brake/clutch/washer lines and and wires. I pulled the cable out attached to the box. I couldn't see it to disconnect it in the car. Maybe I wasn't looking in the right hole.

Do the gaskets fit tight? Is that why it is such a bear to get the box back in? I've read somewhere to use a lubricant.

Also, I want to clean and paint the ducts/passages with a rust encapsulator. So I'll scrape out the loose stuff. There is a screen over the firewall opening. Does that screen come off and go back on EASILY? It would give me another hole to work through. I will always wonder if someone says a car is rust-free, have they looked in the heater?

"Worse than a transmission?!?" Dang! I'm glad I'm doing this to take care of the surface rust. If push comes to shove maybe this will be a heater delete. I don't drive it in the winter. This won't go back in until after the respray, in the spring, so I'll see what happens.

I always wonder how they put them together in Abingdon. I can imagine Clive, who works on the assembly line coming home and telling his wife "Good news, dear. I assembled 3 heaters in MGBs today. A plant record, I'll get a bonus."

Thanks for the info.
 
That cable reassembly can be a challenge, fer sure.
 
Lynn Kirkpatrick said:
I always wonder how they put them together in Abingdon. I can imagine Clive, who works on the assembly line coming home and telling his wife "Good news, dear. I assembled 3 heaters in MGBs today. A plant record, I'll get a bonus."
Click to expand...


Very good Lynn! :lol::jester:
 
Hi the heater unit for the MGB has 5 screws at the bottom hold the box in place and one at the top, you have to undo the cable at the bottom of heater box best to cut it and buy a new cable faster that way to get the heater unit out, now its out good time to look at the rad and seals I have new seals, also look at the heater motor and test it if you need a new one the good news is you buy a new one as I make the heater motor and heater fan lots more photos on my face book page https://www.facebook.com/pages/Ashley-Hinton/245648178847505?fref=ts
Regards Ashley Hinton
h_mgb.jpg
 
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