Run Allison Transmission oil pump with engine off

[Freeebird]

I guess I can understand your logic, but locking down a shaft would still be the simplest way to go. I have a fair amount of single engine running with a twin engine boat experience, and the easiest method I found was to take an open end wrench and place it on one of the bolts at the tailshaft of the transmission in such a way that it locks against a stringer. When you find yourself in need of that particular engine/transmission, just fire it up, throw it into reverse, and the wrench comes off without ever having to leave the helm. That comes in real handy in an emergency situation.

Granted I never tried that at any speed to speak of, so I'm not sure what you could get into with loosening or overtightening a bolt like that.

[sailorryan]

I guess I can understand your logic, but locking down a shaft would still be the simplest way to go. I have a fair amount of single engine running with a twin engine boat experience, and the easiest method I found was to take an open end wrench and place it on one of the bolts at the tailshaft of the transmission in such a way that it locks against a stringer. When you find yourself in need of that particular engine/transmission, just fire it up, throw it into reverse, and the wrench comes off without ever having to leave the helm. That comes in real handy in an emergency situation.

Granted I never tried that at any speed to speak of, so I'm not sure what you could get into with loosening or overtightening a bolt like that.

There was a similar setup here that I used at first but it got lose and caused a metal strut to fly thru the engine room.

I have looked at options others suggested (wrench, pipe wrench, piece of hardwood) but am not sure of long term use, plus danger of hurting someone like before.

Do you have pics of our setup? I am curious to see how you made it.

What kind of performance hits do you have vs free spinning? ie speed at constance RPM, and steering force issues? (At first blush seems like would help steering, at the expense of added drag)

[Boatsb]

Check out the Viking / Gulfstar motor yachts or maybe the bigger bayliners. Theres no reason to mutilate a nice boat like a hatteras.

Remember that there were a bunch of very good engineers in the factory that did a pretty good job. $4/Gal diesel is not an excuse. Hell its more than that in the islands. Open up your wallet. You choose to live there so deal with it or buy a sailboat.

[sailorryan]

Check out the Viking / Gulfstar motor yachts or maybe the bigger bayliners. Theres no reason to mutilate a nice boat like a hatteras.

Remember that there were a bunch of very good engineers in the factory that did a pretty good job. $4/Gal diesel is not an excuse. Hell its more than that in the islands. Open up your wallet. You choose to live there so deal with it or buy a sailboat.

We already own the Hatteras....and we have sailboats. Adding a secondary oil pump is not IMO mutilating the boat. Between us and the previous owners, this thing is immaculate and only getting better as we add more amenities.

Fuel is not the primary reason we are a "go slow" family.

[hmccoy99]

you have the option to lock up one engine. with the "get home mode" of a allison M20 ... its
fairly simple to remove a cover plant and screw in the lock bolt..

no ware.. then run the single engine

look it up in the allison manual.

Henry

[hmccoy99]

but it would be just as economic to idle them both.. in my opinion

henry

[jim rosenthal]

Why don't you just idle the engine you "don't need", and then switch working engines every hour or two?

[sailorryan]

you have the option to lock up one engine. with the "get home mode" of a allison M20 ... its
fairly simple to remove a cover plant and screw in the lock bolt..

no ware.. then run the single engine

look it up in the allison manual.

Henry

I will check this out. Thanks!

[sailorryan]

but it would be just as economic to idle them both.. in my opinion

henry

Idling for long periods of time is damaging to DDs. Its not a good idea, you need to load them up and keep them hot.

[Freeebird]

There was a similar setup here that I used at first but it got lose and caused a metal strut to fly thru the engine room.

I have looked at options others suggested (wrench, pipe wrench, piece of hardwood) but am not sure of long term use, plus danger of hurting someone like before.

Do you have pics of our setup? I am curious to see how you made it.

What kind of performance hits do you have vs free spinning? ie speed at constance RPM, and steering force issues? (At first blush seems like would help steering, at the expense of added drag)

Oh, you want a pic of my setup? Okay, here you go, but it seemed simpler just to buy one vs making one.



Not sure how you could manage to launch a wrench anywhere if you do what I suggested, let alone cause a metal strut to fly anywhere. The wrench will simply fall off when you remove the pressure by placing that transmission in reverse. As for performance, removing a prop is the only way to maximize efficiency, and that's exactly what I did on a 1,000+ mile run. You could always do the same if you want to run each engine six months out of the year. Yes, I'm being a tad sarcastic, but hey, you asked, and it would work. You could run the propless engine up to speed and temp to keep it ready for its turn. How much is your time worth?