M109 Self propelled gun info needed

[jdmcm]

Are any of those vehicles you mentioned Rob, powered from the rear? Or are they all front drive like the M109? The marines at Camp Pendleton were working on a few different self propelled guns so it is very possible it came from a different version than the M109...as long as they are all powered from the front and David has it nailed on the rotation of the T-55/55/62 final drive input...this thing is feasible...

[rob love]

All are powered at the front.

The manual talks about which way the rotation of the flanges and drives are (clockwise or counterclockwise). I can give you the manual number and you can compare the drive of your xmsn with the final drives of the receiving tank and see if things are going to match up.

Manual can be downloaded here: http://www.liberatedmanuals.com/TM-9-2520-234-35.pdf

The manual also mentions that the outputs are not necessarily left and right of the vehicle. It is considered that the transmission side that faces the engine is considered the front of the transmission, so left and right are off of that point. And the left and right outputs are reversed to right and left if the drive units are attached to the transmission.

[Malcolm Towrie]

John, just curious, why are you considering using this pack in a T55?
Malcolm

[David Herbert]

Possibly because although the original T55 engine is excellent, the transmission isn't. The whole thing is just plain crude. The service clutch is a metal to metal dry multiplate clutch which never fully disengages. If you are stationary, in gear for more than ten seconds the plates get hot, warp and engage themselves. Primary gearbox is simply crude, fan drive is unbelievably noisy, particularly at idle when you can hear the backlash in the gear train banging back and fourth. It also has clutch and brake steering which is just dangerous at the speeds that it is capable of driving. Note that all T55 / T62 in news programs have the fenders rounded off on all four corners, there is a reason for that !

Having said that, it is I believe the worlds most prolific tank family so someone loves them and we must remember that they were built for fighting in wide open spaces, not for the semi urban environment that western armour finds itself in.

David

[jdmcm]

Malcolm

we came across one, T-54, that has been de-milled by cutting out all the engine bay fittings, all that is left is the steering clutches/brakes attached to the final drives. As everything is worth saving, this seemed like a way to make a very functional, easily maintained and arguably better running tank, with parts available anywhere in North America. When we got the, what I call M109 pack for ease of description, ...we had thought about it for our Type 69, but that tank had such an fascinating story/history we decided best to keep it as original so we sourced a couple decent motors for it and left it how it was built.

John

[rob love]

When I check the parts manual for the ARV, the transmission pack is referred to as "M109/M578", so perhaps it is not much more than a change of the flanges. It is going back quite a while but I remember some differences in the generator or cooling systems between the two.

[Malcolm Towrie]

On the attachment in post 39, what is the "throttle shaft" for on the tranny? Engine load input?
Malcolm