1972 CAT D4D overheating

[Cash4Toys]

Yes, the bigger one is part of the bypass system. The small one - idk.
Picture attached.

Yes, the bigger one is part of the bypass system. The small one - idk.
Picture attached.

Okay ,those are both steel lines, but you had mentioned a rubber hose that was firm when thermostat was closed, pliable when open. Where does that hose start and stop? Another question, if that's a power shift, it must have a cooler as well. Assuming that's a water to oil cooler where is that at? Does you manual say anything about bleeding the cooling system?

 

[Greenfielrider]

Okay ,those are both steel lines, but you had mentioned a rubber hose that was firm when thermostat was closed, pliable when open. Where does that hose start and stop? Another question, if that's a power shift, it must have a cooler as well. Assuming that's a water to oil cooler where is that at? Does you manual say anything about bleeding the cooling system?

This hose is now firm no matter if the thermostat is open or closed. I think the old water pump was shot.
The new water pump fixed this.

It has power shift and yes - a cooler for that.

Unfortunately the manual doesn’t say anything about bleeding the cooling system.

 

[Cash4Toys]

This hose is now firm no matter if the thermostat is open or closed. I think the old water pump was shot.
The new water pump fixed this.

It has power shift and yes - a cooler for that.

Unfortunately the manual doesn’t say anything about bleeding the cooling system.

So line marked S by you in the picture you attached comes in close to the bypass line, all near the temperature sending unit. Where does that small line go from there? Have you had that line off ?

 

[Greenfielrider]

The small line also goes to the water pump.

Yes, I had it off to install the new water pump.

 

[Jerry/MT]

This hose is now firm no matter if the thermostat is open or closed. I think the old water pump was shot.
The new water pump fixed this.

It has power shift and yes - a cooler for that.

Unfortunately the manual doesn’t say anything about bleeding the cooling system.

How is the "internal bypass", (10 in the diagram) supposed to work?

 

[black60church]

This hose is now firm no matter if the thermostat is open or closed. I think the old water pump was shot.
The new water pump fixed this.

It has power shift and yes - a cooler for that.

Unfortunately the manual doesn’t say anything about bleeding the cooling system.

 

[Cash4Toys]

I was thinking about you and if you had found a cure for the over heating issue. Now you say the water cured this, so to clarify, the water pump cured the heat issue or the spongy hose issue? Or both?

 

[Greenfielrider]

I was thinking about you and if you had found a cure for the over heating issue. Now you say the water cured this, so to clarify, the water pump cured the heat issue or the spongy hose issue? Or both?

Sorry that I didn’t give a final update on this.

The dozer had 2 issues:
1. Water pump was shot (oil seal worn)
2. Radiator. Badly clogged, I cleaned it chemically (NOT the stuff you get from a auto parts store) but at some point I will replace it. I now have around 3 hours of working time before it’s overheating. Which is very annoying but okay-ish for me.

 

[Cash4Toys]

Okay. Looking at the cooling system flow chart diagram, it looks like the water flows through the engine oil cooler then to the rear of the block around the cylinders forward and upward through the head. So, is it possible that the engine oil cooler head or cooler itself has some restrictions? I don't have access to a service manual or parts book, but if you do a little studying wouldn't heart. I believe the transmission cooler is in between there, but would not have priority.