Hey guys,

I'm fairly confused by the cooling system of this engine, and the ambiguous labels in the service manual aren't helping. Since I'm doing a custom cooling system I need to figure out the flow direction and when fluid will run for certain pipes.

Sorry in advance for the awful color choice but hopefully it will help you guys explain to me how this cooling system works.



Okay so here is what I think so far based on what I have found in the service manual. The format I'm going to use is
Number - flow direction color - when it flows

Here is what I think so far.

1 - Pink - constantly once the thermo stat has opened.
2 - Yellow?? - ?
3 - Pink -
4 - Yellow (The line is labeled "Surge Tank Outlet" in the service manual) - ?
5 - Pink - ?
6 - Pink - ?
7 - Heater outlet
8 - heater inlet

Another question I have is the service manual labels both 4 and 5 as surge tank outlet. Where is the surge tank inlet? I understand that the surge tank has an air bleed just above the radiator inlet. Or does 4 flow in pink and 5 flows in pink and 6 picks up the slack and changes the level of the surge tank that way?

Thanks again.

 

I wasn't really thinking when I worded this. I also need to know what the flow direction is when the engine is cold, and what the flow direction is for when its hot, as I realize that the flow direction for the surge tank will depend on whether the radiator is trying to expand some fluid out or needs more fluid.

 

Okay so the service manual says that 7 is the heater outlet and 8 is the heater inlet. So I'll edit that in my original post.

Also these two pictures I found on tonkin online parts have been helping me piece together how this cooling system works, so hopefully it can aid out anyone else trying to help me figure out the flow directions.





Thanks