THE HEAT IS ON, OR SOON ANYWAY
In preparation for the planned spring adventure I've moved on to fixing the heater. Last summer I found out that the heater valve was leaking and I simply solved it by looping the heater fittings at the engine.
The heater box was removed in a jiffy, or not... Even in an old car its cramped working under the dash. The glove box was removed, the heater controls also, and the fan motor was disconnected. I tried to remove the fan and motor first for easier removal of the heater box, but there wasn't enough room down to the transmission tunnel to get the fan out. So, the heater box eventually came out as a complete assembly.
I removed the heater valve and soon discovered that the leak came from between the copper valve housing and the control mechanism base plate. Next problem – the heater valve assembly isn't really serviceable since both the valve housing and mechanism housing have tabs that fit in to slots in the base plate and they are then bent, or pressed down, to firmly attach each housing to the plate.
“No problem”, I thought, “I just pry those tabs back straight”. Between the valve housing and the base plate I found that there was a rubber membrane sealing of the water side against the base plate, and that was cracked. I proceeded to make a new membrane from a flat rubber mat, and then thoroughly cleaning the valve housing and base plate. Then I clamped the base plate in the vice and bent the tabs of the valve housing back with a hammer and a driver. Tightness testing next…, it failed miserably. I hadn't got nowhere near enough clamping force between the base plate, the sealing membrane and the valve housing.
At work I could borrow a press and I made up two dies to press the valve housing on to the base plate. I almost got it tight, but then I decided to fix the still leaky part by hand and ruined it.
It was a fun experiment, but essentially the heater valve is scrap now. However I will keep it for future reference and if I decide to try fixing it at a later date.
Fortunately the heater core was completely tight, with no external leakages. All the parts of the heater box got a good clean, and new sealing strips were applied where required. The build-in switch that turns the fan on at full speed when demister position is chosen was not working, again not really serviceable, it was riveted together and to the heater box. Nothing a drill and later some sheet metal screws could fix. The switch was thoroughly cleaned and the terminals were freed from oxidation, so now it works beautiful again. Also the baffles in the heater box was probably misaligned before, but they move with ease now, and have a satisfying “thunk” at the end positions.
So, coolant needs to go through the heater core to get any warmth in the cabin. With the original heater valve removed routing of the hoses will of course be different. The only way I could route them is not ideal from a chafing and kinking perspective, but they will flow coolant and uses the original holes in the bulkhead. On the “bracket” on the side of the valve cover (originally intended for the heater hoses?) I mounted a household water ball valve and run the hoses by that.
The heater fittings at the engine (in the thermostat housing and coolant pump housing, respectively) had seen better days and the coolant pump one even had a rust hole at the hose bulge. When removing them I broke the later, level with pump housing. There's where I'm at at the moment. I have found new fittings and they have even already landed in my mail box. Now I just need to get the broken-of part of the fitting, that still is in the coolant pump housing, out.
But wait there's more: While I was under the dash and fiddling around I thought that now is a good opportunity to rout the USB charging port properly so it wasn't dangling freely in the glove compartment. I enlarged one of the blocked-of holes in the dash panel to fit the USB socket, then I tested the windshield washer and it worked, it was just the ground cable and the floor switch that was bad. Another blocked-of hole in the dash was enlarged to accept a new momentary switch for the washer.
Both the USB charging port and the washer motor are now driven through respective new fused relays controlled by the ignition, and in the case of the washer motor also controlled in conjunction with the momentary switch in the dash.
Before removal of the heater box
The heater valve assembly
Tightness testing the heater core
Disassembling the heater valve. Valve housing to the left and control mechanism with housing to the right.
Cracked heater valve sealing membrane
All parts of the heater valve. Base plate top right and the valve it-self middle right.
New, self-made sealing membrane in place
Dies to press the heater valve housing to the base plate
Dies to press the heater valve housing to the base plate, in the vice for trial-fit
The result after pressing in the press
Heater box disassembled. In the process of replacing crusty old sealing strips.
Dismist fan switch working again.
These old style hose clamps are cool. I'll hang on to them and possibly renovate them in the future.
Heater box ready for re-mounting. (Yes, it's upside-down here...)
Heater fitting, engine side. The not-so-broken one.
Rewired windsheild washer.
The new heater valve and hoses.
12V supply and ignition controll signal taken from the starter motor solenoid.
USB charging port and windshield washer relays, and some colourfull spaghetti.
The new additions to the dash panel. Especially the USB charging port looks quite out of place, but function always goes before style in my cars.
Heater box re-fitted and hoses run to the engine compartment.
A look at the backside of the dash panel.
Oh, yes. I also fitted a new windshield washer nozzle.
Here's how USB charging ports and windshield washer are wired. I made this up to remember how I connected it all. Thanks to
https://www.electrical-symbols.com/ for most of the symbols.