Here is a HT HG one I prepared later.

Hi Jack, Im not really sure about what you are saying as I havent really noticed it. The two types are made of different materials. The white/grey ones are polyester (I think) and the black ones are some sort of "cardboard" type stuff (possibly resin coated). The white ones are basically HK and the black HT HG, but the black may have been introduced before the end of HK. There are other small differences, like one of the heater core outlet holes is bigger on HT HG so the core with nipple can fit through.

I just dismantle it completely and then do the zinc plating in my back room.

Any chance of a rundown on the zinc plating process? I had no idea it was something that could be done at home


Pete

Hi PVS, Unless you have 2 different ones together it wouldn't be easy to know what to look for but, looking at the HK one show here, the top one. On both halves of the case either side of the bolts, that hold the 2 halves together, there is some webbing to strengthen the case. On some cases that webbing is quite distinctly heavier. Of the 4 I have the 2 white HK ones are different. You will also find some fan blades are metal some are plastic. There are also, at least on the HK ones anyway there are dates on some parts. Some stencilled sone stamped. If you have cleaned it the stencil one will most likely have been cleaned off. The 2 cases you have there most likely have the same part number cast into them also. But yes you appear to have done a good job cleaning these 2 up.

Jack

Hi PVS Do you sell these?
Cheers.
Nick.

I think you will find The difference is the HK air flow and water flow are controlled and the HT-G only the air flow is controlled. As mentioned above, the cores or tanks are all the same other than the inlet and outlet pipes, For HT-G both inlet and outlet are the same size and shape with a rib to take the water hoses and clamps. On The HK unit only the outlet pipe has a rib on it to take the hose and clamp. The water control valve, the gold one in the photo above, is bolted to the case and seals on to the inlet pipe with an O ring. To modify a HT-G tank to use for a HK unit is pretty simple by just cutting the rib off inlet pipe to the required length and bolt on the HK water control valve. Not so easy though modifying HK core to suit the HT-G unit. The HK inlet pipe is shorter and using the correct tool to form the rib is not so easy and unless you are experienced at welding or soldering radiators be careful attempting to extend the pipe. But to answer your question; are they interchangeable ? Yes ! If all you want is to heat the car then the HT-G one you have will bolt in to your HK ok and with necessary adjustment to control cable and water hoses needed it will do the job.
Jack

Get a control valve for a HK heater and mate it up to the HG box you already have, along with the minor modifications the the HG core, will get you very close to the original factory look and operation. The CASE for the HK heater unit and HG heater unit have the same part number . The difference between the two cases is the material they are made from and the colour.
Jack

Thanks again for all the help.

gain, answered my own question 2doorstore sells a foam kit and a really helpful person to.