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MG TD TF 1500 Questions about Arnolt heater plumbing BBS discussion at MG-Cars.net
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MG TD TF 1500 - Questions about Arnolt heater plumbing
| I know there are discussions about this, but I do not have the "correct" adapters, so I'm having to make "do"... I am running one side of the heater core to the by-pass hose , by way of a "T" fitting off the hose. This side has a ball-type shut off, with a lever. It's the other side that has me stumped... I am planning on running the other side, from the rear plate , on the head, directly into the other side of the core... Does this present any problems? Will I get enough heat, once the thermostat opens?.... If this is not a good connection, what would be better? Thanks Edward |
| E.B. Wesson |
| Edward -- The best way to go is the way the factory did it on the TF1500. Put a fitting in the elbow on the front of the head! Yeah, I know the factory never supplied heaters but they did make provision for one on the TF1500's. The hottest water is there right below the thermostat. The coolest water is at the plate on the rear of the head. (although some people claim they get enough heat taking water from there). There are many threads in the archives about this. If you need help getting the fitting in the elbow maybe I can help. Cheers, Bob |
| Bob Jeffers |
| Edward I run my Arnolt heater the same way that said. I live in Ohio and run the car 12 months a year. It may not be the best way but I get by with it. Safety Fast Tom |
| T. L. Manion Thomas |
| Bob I would hate to mess up that elbow, if I didn't get a good weld, or connection....Sounds like a good, if difficult, option. Tom Are you saying that you are running the heater as I have mentioned, or the way Bob is doing it? I live in NE Georgia, and , we get cold weather, but nothing like you would get in Ohio. Thanks for the input. Edward |
| E.B. Wesson |
| Ed, Do you have a picture of your shut off? Mort |
| Mort TD 1851 |
| ...tapping the elbow is pretty easy and a couple pipe fittings give you a good connection.... it is the hottest water in the system... returning can be through the lower rad hose.... I'm not one for changing the bypass system....makes me nervous...  |
| gblawson(gordon- TD27667) |
| edward, for what it's worth, i tap off the rear plate and the lower radiator hose as you are talking about. i live in northern illinois and i am satisfied. a strong advocate of the front elbow method, here on the forum, provided water temperatures at the various locations and the difference between "hottest" and rear plate tap was, in my opinion, insignificant. regards, tom |
| tom peterson |
| Ed, I tapped the elbow for the thermocouple connection. No weld. Just some sealant. No problems. Mort  |
| Mort TD 1851 |
The TF lower return pipe with heater shut off. PJ |
| Paul J |
| PJ, If I understand your picture it seems that with the shut off closed it stops the flow to the radiator. Circulation would be just thru the engine compartments and after the thermostat opened there would be minimal circulation of cooler water from the radiator. I was looking for a set up that just closes the flow to the heater without impeding flow to the radiator or engine. Mort |
| Mort TD 1851 |
...temps....
 |
| gblawson(gordon- TD27667) |
| Wow! All kinds of info here... I have tried to see details of the "original" installation, shown in the Arnolt instruction book (seen in the Archive), but can't make out any real details, other than the twin pipes on the passenger side of the valve cover.... One appears to go into the bypass pipe, but I don't know where the other one goes. I do not have any of the adapters, but could make one, if I knew what was needed..Does anyone have that info? Edward |
| E.B. Wesson |
Although not an original it is built in the same fashon. The large pipe is blocked off between the two outlets. As you can see the flow out and back was at the same fitting.
 |
| LaVerne |
| Mort, It doesn't impede the flow, it just stops the flow through the heater. With the valve shut off, it's the same as if you plugged both sides with no heater installed. Doesn't affect the main cooling system at all. The 1500 TF are slightly different than the TDs. Pressure comes from below the thermostat housing. PJ |
| Paul J |
| ....inside the fitting... On the ones I have seen there is a washer like piece welded in place... that lets some water through but most goes through the heater.... I'm assuming you can't turn off the water supply to the heater....thats why i did mine the way i did....with a shut off valve at the firewall.... This is also the coldest water going through the heater.....  |
| gblawson(gordon- TD27667) |
| Gordon I've posted this photo on another similar thread, but here it is again. I need to know if I'm going to get heat without damaging anything. Nothing is actually connected yet. Edward  |
| E.B. Wesson |
| Here's an image of an original Arnolt adapter. It's 3 inches long and diverts all of the bypass liquid through the heater. When installed, I have a control valve behind the heater that I can control from a panel attached to the dash. By use of the valve I can emulate the action of the original thermostat. Take a look at http://www.ttalk.info/modern_thermostat.htm for my thermostat installation. Bud  |
| Bud Krueger (TD10855) |
| Do you have the original thermostat in it? There is a brass ring that covers the bypass hole when the thermostat opens...that would prevent water from going into the heater when the engine was hot? |
| gblawson(gordon- TD27667) |
| Gordon I do not know which thermostat is in the housing, as it is the one the car came with, and I haven't yet taken it apart.... I'm leaning toward the method that Arnolt used, by making the dual inlet pipe with a restrictor....This, evidently , allows flow to the block when the thermostat is closed, but also diverts part of the flow to the heater when open. Edward |
| E.B. Wesson |
| Here is an image of my TF's original Arnolt heater fittings(I temporarily misplaced the return pipe) The shut off is before the firewall, the two pipes run along the top of the manifold and the water returns to the same fitting (the pipe is blocked inside between the two branches). Looks slick when installed. JB  |
| J K Barter |
| JB Thanks for the photo...Essentially, that is what I am fabricating.... I will post construction photos of the bypass pipe, and plumbing as soon as I get it all together. Edward |
| E.B. Wesson |
| One addtional note... I checked temps of the various hoses with my infra-red thermometer, right after a 20 mile drive... The bypass hose read 165 degrees.... To me, and where I live, this should be plenty hot enough for my heater. Edward |
| E.B. Wesson |
This thread was discussed between 04/05/2011 and 08/05/2011
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