Allison Gears- No Forward Gear- Resolved

[Genevatexan]

Guys,
Just wanted to say thanks for the great guidance on this. I got the Hydreco transmission pump rebuilt by Acadian Marine in Louisiana, built up a new pressure guage on the gear selector lever housing, reloaded the oil and now have 142 lbs of pressure at neutral and my forward gear back working. I verified that the mechanical tach drive rotated smoothly when re-engaged with the pump, with no binds, but found the tach not reading following installation, so I will need to back up and trouble shoot that.
Otherwise, super happy, no gearbox failure, back on the water.
Again, can't thank you enough. Happy New Year!

 

[Boatnut]

Thanks for the reply on the solution. I sure appreciate it, as will several others. Glad all is well and your back on the water.

Happy New Year to you as well.

 

[MikeP]

142 in neutral is considerable higher than the specs in the Allison tranny manual call for; interesting that they would set it up at that pressure. Good Info - perhaps their experience is that the higher pressure is helpful.

Did you (or a mechanic) set it at that pressure once reinstalled based on Arcadian recommendation or is that the pressure that the pump showed as received from the rebuild and reinstalled?

 

[Genevatexan]

Mike, Brian at Acadian set it up at that pressure but had commented earlier that the normal operating range for this application would be about 130 lbs. Is the adjuster the large stacked hex nut on the pump? Probably should dial it down...Brian did say "you may need to make some small adjustments...".