Hello everyone.

ACMOC newbie here. Last summer I bought an 80 year old wooden tug in Seattle with a rebuilt D337 installed in 1964. (Serial number 23B102, Snow-Nabstedt 4.5:1 reversing gear, Rootes Blower, ~5500 hours). The motor runs great, and I want to keep it around for another twenty years, so I want to set up a program to take care of it. This is my first tractor motor.

Last month the engine block heater shorted out. It includes a single 110v cable that spits and connects to an element on the heat exchanger at the front of the engine and to an element on the block. The plug to the element on the block shorted out. I have included a couple of photos.

Any suggestions where I can buy a replacement element or assembly?

I will have many more questions for this group. I am glad to be owning a piece of history.

Thanks,

James

Here are the photos.

Welcome, I would remove the heater element from the housing and take it to a heavy truck parts store and compare it to a new one, Zero-Start or Kats brand heater. 
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Hope what Rome suggested works and if not try john Deere. It looks similar to one on my old 4440. (1500 W)

congrats on your purchase, sounds like she's in good hands..like to ride on a tugboat one day (hint)
-not sure on what you require part wise, but Rome is spot on, nothing like having the actual part in hand to match up or whatever...whenever you go to parts store (rule number one)

-my 3306 came with a basket of parts, one was a block heater....never seen one like it...but the element was 4-5 inches long, and i think 1200 watts...easy to install...
works great
-i think they're very effective to keep the frost out so a great choice when you're close to juice.. just a little extra heat when it's go time..