MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG TD TF 1500 - Pipe question for the heater guys?

I'm still thinking about installing my eureka heater in the TD. I've always assumed I would braze a fitting on the rear cover plate on the back of the head and another fitting on the branch pipe between the water pump and the radiator.

Occasionally, I see pipes like this one on ebay: http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1,1&item=4577810965&sspagename=STRK%3AMEWA%3AIT
Is this pipe supposed to replace the branch pipe? (It looks like it would be way too short.) Or is it supposed to provide both connections to the heater, supply and return? Anybody ever use one of these?

Thanks,
Evan
Evan Ford - TD 27621

That's the standard diverter supplied with Arnolt heaters. See http://www.ttalk.info/Tech/Arnolt.html
A problem with using it in conjunction with the standard thermostat is that the OEM thermostat closes off the bypass when the engine gets warm. IMHO, it works great when used with a modern thermostat and a controllable valve.
Bud Krueger

Evan

I use the pipe you listed for my Arnolt. My car came with a spare rear water plate with a hole in it. But the plate was not on the car.

Others have commented that the back plate works well for the heater and some say it is not a good as the front.

If you are interested, I would be happy to send you the plate with the hole in it if you want to try.

contact me at cunhab@charter.net
Bruce Cunha

The discussions of suitability of the rear plate over the front of the head for the hot water outlet for a heater revolves around the temperature of water at either location. I used the rear plate and have been well satisfied with the results, but I live in an area of the country where temperatures are relatively moderate and there not being many times that we are driving at temperatures below freezing. The temperature of the water at the rear plate is cooler than the water at the front end of the head (I don't know how much cooler and was unable to find out with a quick parusal of the various books on the XPAG/XPEG engines that I have, suffice it to say that the water at the front of the head is hotter than at the back for the simple fact that the water flows through the head fron back to front). The final answer is that if you want the hottest water available, take it from the front of the head. This does not mean that one must use one of the Arnalt diverter pipes is the only way to accomplish this. I am just using a tap welded into the elbow between the bypass hose and the inlet to the water pump. This tap is the return line for the water. The inlet water can eaisly be tapped into the thermostat elbow that is installed between the head and the thermostat housing. This is a method of getting the water for the heater very easily. A temperature control for the heater can be the heater valve used on one of the import pickup and installed on the back of hte heater itself. Cheers - Dave
David DuBois

Bud,
Thanks for the link. So, it looks like the arnolt diverter piece replaces the hose between the water bypass and the branch pipe. I see you point on the OEM thermostat, unless the small amount of water not blocked is enough for heat. Didn't Arnolt use this heater connection with OEM thermostats?
Does the Arnolt piece force water to the heater? I assume the main pipe is blocked to keep the water from bypassing the heater?

Bruce,
Do you use this connection with an OEM style thermostat? Do you get enough heat from this setup? (If it's good enough for Wisconsin winter, Ohio would be a no brainer!) Thanks for the offer of the plate, but I might do the Arnolt method instead. (If it is working for you guys.)

Dave,
It would be interesting to compare the temps front and rear with one of those IR thermometers. I would guess the rear plate method would give me sufficient heat. What's a couple of degrees when you are dealing with side curtains! I'm sure cyl #4 generates plenty of hot water.

I guess I'll noodle this a little bit longer....
Evan
Evan Ford - TD 27621

Check you email I will send you pics of the one on my car. It's very simple and works great with my Bosch heater unit.
If I could do it on the site I would.
Colin Stafford

Evan

To be honest, I don't know if my thermostat is OEM. It is what I have had in the car for many years. I get ok heat, but then I only use it into October to give some additional foot warming. Car goes in to storage prior to the winter weather.



Bruce Cunha

Evan,
The bypass fitting you have seen is to be used inline with the upper radiator bypass hose. The hose is cut and sectioned with this fitting. There is a blanking plug in the middle of the fitting that directs coolant through the heater matrix for the maximum heat exchange. The feed and return functions are both incorporated into this fitting, first used on the Arnolt heaters in the early 50s. After the coolant has gone through the heater, it is returned back to the upper radiator hose and then to the upper radiator tank. You can also take coolant off the back of the head and return it to the water pump however this involves a bit more plumbing. Ben
Ben Cordsen

Thanks Ben!

Exactly what I wanted to know. Now I guess it's just a matter of how much flow there is when the bypass is closed.

Evan Ford - TD 27621

I have found over the summer that having an "off" valve saved my right foot (and leg) from burning... I thought that little bypass meant that heat would be going throught the heater all the time?
(just got back from a week's vacation which involved ambulances and falls from boat to docks so a bit woozy...??? and not understanding the pipe?)
My heater has been on the last two weeks and just takes the chill off.....!!!!!
gordon lawson

This thread was discussed between 28/09/2005 and 30/09/2005

MG TD TF 1500 index

This thread is from the archive. The Live MG TD TF 1500 BBS is active now.