I was looking at a D8 the other day and was told it would pull poorly when hot. Is this a torque convertor about to go? Seems to be ok when cold.

Could be, what model are we talking about??

I worked on a D8D for a friend a few years back, That thing had a fuel fed torque converter. What a pain to bleed and it did the same thing that you discribe. Maybe it is the same one? Also we found that the pony was put together with only one piston in it!!! I'm not sure how it ran and started the tractor but it did. I think it was a 1958. The machine was in the Monroe Connecticut area but has been sold since. Dave!

It,s been years since I primed a torque so I checked the operators manual & it came back to me but first remove floor plate over the torque & open the vent valve on the upper area of the torque convertor housing & open up the cap on the main fuel tank to give it air.There is a crossover valve then in the system to open & put the scratched line on the turning part of the valve in a horizonal position. When the fuel runs out of the open vent valve with no air in it then close off everything & it should be ready to go.Upon starting the diesel the torque gauge should go to the normal white position of the gauge & if not the book says there still is air in the system so then I guess re-priming will be necessary again.

I don't know if this is applicable to your Cat or not. A friend of mine had an old Allis-Chalmers HD-16 with a fuel fed torque converter. According to him the machine ran fine, but when the fuel tank got too low the machine had no power. Hope this helps.

I remember there being a strainer in a line from the fuel torque on a 15A I once operated. It was on the front of the front cylinder head. I don't even know what a D8D is but I thought I'd mention it.Phil

Phil a D8D is a 15A up to 15A1672 & then it is a 15A D8G.The operators manual tells all about bleeding out & filling the torque & yes there is a filter just for the torque.There is a couple other things it explains too. HB11 if you can find a operators manual book get the one listed for 15A 1 & up & it also covers the 14A.

Thanks SJ, that 15A was really a big improvement over the 2U I was operating when I was 15. My father let me try it out one day, just for a few hours, I remember the bark it made and stalling it seemed impossible. The torque converter seemed like such a huge improvement. When he brought it to the job site from the auction, the first tree he pushed over started a loud knock in the engine. They used maple logs to build a frame over the machine and pulled the engine out. I think I have a picture. Backing a float under it, the engine had it's crank replaced right there, with one from "up north". The new crankshaft was covered with rust but Crothers Cat said it might clean up and they would sell it cheap. The oil pan was full of shim stock, he said. My Dad said it snowed that day, the 1st of June which is very rare for southern Ontario. The 2U though gave me a good set of biceps. It was a "HI-Output" 2U. Phil