Hd5 loader engine swap ?

New guy here. A little backstory, I picked up an old hd5 tracto shovel loader model a while back. I got it running and repaired the cracked head(freeze). The water pump was missing so I installed an inline electric and electric fan. All was running decent using it in my crawfish pond cleanup project. It seems to be slightly underpowered but I have nothing to compare to. Today something in the engine let go at 3/4 throttle. I'm pretty mechanically inclined and have most every mechanic and welding tool you can ask for. I will take it down this weekend to find the problem. In the meantime I am very interested in swapping in a 3-71 anyway for the power gain. I've been lurking and reading here since I got the machine. I saw mention and searched but can't find much information. Any help and pointing at swaps done would be greatly appreciated.

Thanks in advance , Scott

Thanks for the reply. That's definitely food for thought. Maybe mine wasn't running to full potential. I couldn't find anyone in south Louisiana that had experience with on to compare.

the rear section of the HD6 is the same as HD5 so most except engine is the same in the power to ground - track - sprocket - rollers- idlers - but loader frame updated along with bigger engine . 

You would go from 142 cubs to 159, not much increase, probably a bit smoother running, thinking the torque is about the same.  Did Detroit use the same rods in 53's as 71"s or where they shorter?

Our HD-5 has the 3-71 Detroit installed. These tractors were done by Sweeney Brothers Tractor Co in North Dakota & Minnesota for drawbar work. I have seen two others beside ours. The 3-71 is taller than the 2-71 so they added material to bring the engine enclosure up probably 8 inches. The engine pushes the radiator forward as well. Headlights have to go to accommodate it. All that aside, in talking to the farmer that had one that I tried to buy, the 3-71 made a farm tractor at that time out of the HD-5. Fitting it into a loader tractor may be another story, however.

Seems the HD5G I had would out push the HD5B with the 9' blade - could move dirt faster with the G . As far as power a 1 yard machines only moves so much material no matter what the HP as the gearing and track only allows so much power before the track slips or machine stalls. 

Re build the two banger. One of the reasons we are still talking about tractors built in the late 40"s early 50's is that they were a little under powered. Heavy structural deflection was not an issue. Smashing the tranny and under carriage was not a huge issue. But good operators could do a LOT with the one yard bucket. My Dad dug many, many basements, cleaned corrals, buried horses, loaded thousands of yards of gravel/sand, pushed snow, dug dugouts etc. etc., mostly for free as a good neighbor. He is 85 now and says that he occasionally has a dream where he wakes up with his feet up in the air as he has been running the "cat" in his sleep ! They are one of the all time greats, yours looks good, JMHO, Trev.

As mentioned... put in slightly bigger injectors but checking the timing is also important. Depending on the mechanic that last did it...I had one Detroit with timing set according to the book and it was pretty lame I thought. Advancing a little can put the snap back in that you're looking for (even a valve adjustment can make a difference). If the compression is low you still need new kits to get back what has been lost. The 53 series rods are shorter as that is a higher revving engine originally designed for boats. Governed RPM usually 2800 where the 71 series is around 2150. Of the two I like the 71 series better.

Coke-in-MN wrote: HV 7 injectors are used in the HD5 / 2-71 engine - as they are set with a plug gauge into injector body - to set the height of the injection piston to rocker action -   Can up the RPM some on governor and gain a little power also .

Not everyone has the ability to "feel" the timing dimension. If it isn't right it will be a dog.

Edited by SteveM C/IL - 26 Sep 2016 at 8:54pm

you may have to change the bell housing and flywheel, governor linkage to match the loader but everything else should be the same. I had one from a stationary engine, not sure what it ran, sold it and it went right into a loader. good luck,