View Full Version : D25U heater removal

12-17-2006, 06:38 PM
I've got a D2 5u that came from north of Winnipeg and has a heater installed between the water pump and a pony head. Baby Huey lives in Houston, TX and I don't anticipate the need for a heater (temps have been running in the 70s and lower 80s this mid December week). When we do get a cold snap and the temps drop into the 40s, I probably won't abuse myself to such extreme temperature and therefore won't require my D2 to do the same. I sure wouldn't ask my tractor to do anything I wouldn't do.

Anyway, the tap coming out of the water pump looks about 3/4" but the fitting coming out of the head looks like its not threaded. I'd like to plug both ends and loose the hose connecting the head with the water pump.

Is this advisable or should I just replace the whole assembly sith a hose and live with it?:confused:

Thanks from a cajun that don't do 110 volt power cords coming out the side of my tractors.

Old Magnet
12-17-2006, 06:50 PM
From your description it sounds to me like they have connected to the normal engine cylinder head to pony cylinder head elbow water connection which uses an "O" ring/flange seal. If that is the case just replace the elbow/flange fittings, plug the 3/4 tap and your good to go.

12-17-2006, 07:33 PM
Hi OM,

Thanks for the reply. The fitting on the pony comes right out the front edge of the pony head and sticks forward. Just looks like a 1/2" pipe sticking out the pony head casting. No obvious way to remove it like a hex part of the fitting. I guess its possible to be threaded but threads aren't obvious where the tube enters the head.

I don't have this fitting on my earlier D2 pony head. I just assumed the late models had this connection from the water pump connection to the pony head from the factory.

Worst case, when I dump the antifreeze, if I can't see a obvious way to remove the tube, I'll just pull the heater and replace it with a single hose. I just didn't want to remove something the factory deemed necessary for cooling the pony.


Old Magnet
12-17-2006, 08:29 PM
It's not normal to have the pony head water connection plumbed with a hose from the water pump. The normal connection for the "U" models is an elbow connection from the pony head to the main engine block. The pony head connection would be a nipple that fits through a 2-bolt flange with an "O" ring compression seal. No threads on the nipple. The other end of the elbow is a flange and gasket to the main engine.

If the other D2 you are referring to is a J model they didn't use this elbow fitting.
They had the type seal connection that is sandwiched between the back of the main engine head and about center of the pony manifold.

A picture would help here but I couldn't find one. I can post the picture of the parts breakdown if you like but it does not do justice to the actual installation.

By all means do not lose the hose connection setup without replacing it with the normal setup as that would be the end of your pony cooling water.

12-18-2006, 06:17 AM
I'll post a picture of what I have a little later (it will be a good first attempt at posting a picture for me on the new ACMOC site).

I'm sorry, I should have been a bit more specific on the earlier D2. It's a U model but the first year of production (ser# 435) and the D2 we are discussing is the last year (#17478).

I think the pony retains it's normal cooling plumbing, and this heater was an ad on. If that's the case, it shouldn't hurt to remove the plumbing but I just want to make sure.

Have a nice day!