8v92ta and Allison MH15 - best option for PTO?

[kflod]

I have 8v92ta's with Allison MH15's. I need a PTO for hydraulic thrusters. I know there is a possibility bolting them on the engines, does anyone know how much power you take out from those gears?Also, I see dieselpro sells hydraulic pumps for the Allisons - that would be KY preferred option as I probably could take out more power, but I cannot understand where to install them? Have anyone done this and have pictures or an explanation of how and where it is done?Thanks

 

[jmooney]

I don’t have a thruster, sadly enough, but I have been doing a lot of research. Transmission mounted pumps would be best. The accessory drives on the engine would only support small pumps like a stabilizer pump . This according to Detroit Diesel people in Ft Lauderdale. I have 12-71 engines and Twin-Disc transmissions . Twin-Disc rep told me my transmissions are virtually the only model without a pad for a pto . My only choice is mounting the pumps on the front of the crankshafts . The mounts, electric clutches , and couplings would be almost $7500 per engine. Crankshaft mounted pumps need to be big as they need to work at 600 rpm . A generator mounted pump turns at least 1800 rpm and can be smaller. I wanted a pump on both motors, as I worry about single engine operation in a tight area. I have come to the conclusion that a 12 inch 25 hp thruster from Wesmar would be my best choice. This would be 48 volt dc with a proportional control which would be virtually continuous operation. I would rather have a hydraulic system for the reasons of weight and reliability. I am sure you will receive good advice from someone on this forum who has been down this road.

 

[kflod]

Thanks, I'll look into a crankshaft coupled pump

I don’t have a thruster, sadly enough, but I have been doing a lot of research. Transmission mounted pumps would be best. The accessory drives on the engine would only support small pumps like a stabilizer pump . This according to Detroit Diesel people in Ft Lauderdale. I have 12-71 engines and Twin-Disc transmissions . Twin-Disc rep told me my transmissions are virtually the only model without a pad for a pto . My only choice is mounting the pumps on the front of the crankshafts . The mounts, electric clutches , and couplings would be almost $7500 per engine. Crankshaft mounted pumps need to be big as they need to work at 600 rpm . A generator mounted pump turns at least 1800 rpm and can be smaller. I wanted a pump on both motors, as I worry about single engine operation in a tight area. I have come to the conclusion that a 12 inch 25 hp thruster from Wesmar would be my best choice. This would be 48 volt dc with a proportional control which would be virtually continuous operation. I would rather have a hydraulic system for the reasons of weight and reliability. I am sure you will receive good advice from someone on this forum who has been down this road.

 

[piripucha]

I am not familiar with the 8V92, but on the 8V71 there is a frlyweel port to install a pump. Mine is in the stb engine wich moves the Naid stabilizer hidraulic pump. I belive this port should exist in the 92 s. I hope this helped

 

[jmooney]

I have a friend who had a 63 Viking MY with 8-92s and Allison transmissions. He had pumps on his transmissions and had both bow and stern thrusters.

 

[Passages]

As the owner of a 63' Viking MY with 8-92's and Allison Transmissions, I can share the PO installed 24v DC Sidepower thrusters. Works well.
PO was an engineer so I imagine he researched available options.

 

[Captain Ralph]

I managed a 72Hatt with a 48Vdc Wesmar thruster. Works Great.

I also managed a slightly smaller Hatt with all hydraulics for everything. Stepping over that crank shaft PTO is a real pain. The whole marina wakes up when used.

Hydraulic or electric, IMO; KISS, go electric.

 

[Pascal]

Hydraulic is nice as they can run much longer but electric is fine. We have a SidePower 225 on the 84 LAZZARA I run, 48 vdc. Never had it timing out. Excellent support from Imtra in New Bedford. Recently had to replace the gear box (failed, 9 year old). Imtra has it and shipped it right away.

We mostly use the bow thruster to adjust lines and it s nice not to have to start one of mains time so that

 

[jmooney]

I came to the conclusion about an electric thruster after climbing over a crankshaft mounted hydraulic pump on a Hatteras like mine. It can ruin accessibility.

 

[kelpy]

If you have two generators, you can put PTO on the front of one or both of them if space allows. Not all gens will accomodate a PTO though.
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