Square boxes on the rear of Soviet tanks?

[Doggy]

On the rear of my su122 there's a square box with what looks like a pipe coming out of it. Any idea what it is? It's an odd looking thing.

 

On another tank there's 2 boxes one over each rear mudguard, they look like storage boxes.

 

Thanks in advance.

[Doggy]

https://www.scalemates.com/kits/miniart-35181-su-122-early-production--977239

 

This is the only picture I can find of it.

[Doggy]

https://www.scalemates.com/kits/armorscale-r35-003-soviet-rear-small-fuel-tank-t-34-76--254116

 

So these are small fuel tanks, never knew that.

[Bertie McBoatface]

You've only gone and made me buy a SU122, haven't you! Lol.

 

Thanks for the link, is it as good as the box art suggests?

[Doggy]

The wheels aren't great, the wobble a bit on the axles.

Overall it's decent, typical zvezda.

I've only just painted the red circle on the top.

[HistnScale]

The square box with the pipe setting between the exhaust pipes is a heater for preheating the engine during cold weather.  The crew would dig a trench and place the heater in the bottom.  After getting a fire going much like a charcoal grill fire, they would drive the tank into the trench and over the heater.  Then the whole thing would be covered with a tarp for the night.  Interesting solution to cold starts in sub-zero weather. 

[Doggy]

13 hours ago, HistnScale said:

The square box with the pipe setting between the exhaust pipes is a heater for preheating the engine during cold weather.  The crew would dig a trench and place the heater in the bottom.  After getting a fire going much like a charcoal grill fire, they would drive the tank into the trench and over the heater.  Then the whole thing would be covered with a tarp for the night.  Interesting solution to cold starts in sub-zero weather. 

Thank you. That makes sense looking at the box. There's a clearance on one side that I now assume is to load with firewood or something.

[Doggy]

That's going to raise another question. If it's getting burnt on a regular basis there won't be any paint on it, now I need to figure out how to make it look burnt