D7 3T With Cracked Block - Junk or Can It be Welded?

Is this the same D7 you have been trying to start?
From all the other issues you have posted, time to run away!

Fixing the block is something than needs to be assessed, is this freeze damage or something else.
Maybe other locations that are not as visible are damaged too.
Not as simple as putting an arc and hoping it fixes it.
CTS

Hi Scott, Since you are obviously looking for an old 'dozer here is a D7D for sale near me. The engine runs good. The final drives are leaking. The tractor moves and could be for limited use if the finals were filled with grease instead of oil. I don't know the price. The tractor has been sitting a little over a year, these pics were taken in January. Let me know if you want more info.
Craig
 [attachment=74642]D7D-1.jpg[/attachment]

 [attachment=74643]D7D-2.jpg[/attachment]

 [attachment=74644]D7D-3.jpg[/attachment]

 [attachment=74645]D7D-4.jpg[/attachment]
 

Hi Scott, Since you are obviously looking for an old 'dozer here is a D7D for sale near me. The engine runs good. The final drives are leaking. The tractor moves and could be for limited use if the finals were filled with grease instead of oil. I don't know the price. The tractor has been sitting a little over a year, these pics were taken in January. Let me know if you want more info.
Craig
 [attachment=74642]D7D-1.jpg[/attachment]

 [attachment=74643]D7D-2.jpg[/attachment]

 [attachment=74644]D7D-3.jpg[/attachment]

 [attachment=74645]D7D-4.jpg[/attachment]
 

Hi Scott, I am about 90 miles east of you around Yoakum.
Craig

Hi Scott, I am about 90 miles east of you around Yoakum.
Craig

If you select reply instead of quick reply the quote won't be added. Just click action.
The 3T might be worth it for the undercarriage parts.
Craig

[quote="seiscat post=253385 userid=5422"]If you select reply instead of quick reply the quote won't be added. Just click action.
The 3T might be worth it for the undercarriage parts.
Craig[/quote]

Yeah, that's kind of what I was thinking.  Too bad these aren't that easy to transport and part out.

Scott,
There a a myrid of problems with freeze damage, many totally unseen until they manifest themselves.
Does this 3T have Starting Engine or has it been converted to Direct Electric?
Starting engines depend upon the main engines water pump to cool them, and as such use the same complete system. We had a 9G that had frozen, no question of the damages as the bottom tank of the radiator was gone. Nothing of note in the block but Starting Engine always made water in the oil. Internally, water jacket broke into the valve train area, crack leaked so as long as the engine was running - water was forced into the starting engine, filling the crankcase.

RE: Parting out, do some research!! NOTHING on these is light in weight and a lot of the final drive assembly, dead shaft, etc require specialized tooling.
Caterpillar dealers had 100 ton specialized porta-powers with specialized tooling for pulling and repressing sprockets for example.
If memory serves me correctly, pulling the steering clutches and bevel gear requires access through a small hole on outside of case to reach the bolts, this requires the machine to be moved forward or backward as necessary to reach all the bolts.
Re working track chains is a specialized job too, takes specialized tooling and press to remove pins and bushing, then replacing same.
Unlike Military Track - Caterpillar comes apart at one location, either the Master Link/Pin or in later years, an alligator section of rail.

In short, there is nothing easy or light about tackling major repairs or parting out a D7!

If you do not have one - I would suggest an A frame with track and chain hoist on transverse top bar, rollers, at minimum, wide enough to span the tractor easily and on solid wheels.

Good luck - be safe.
CTS