We have a transmission running at 80 psi which should be around 120 - 140 There is a nut on the side with a another nut inside with a spring Does anyone know if this is adjustable?
Low pressure is usually a sign of low oil in those transmissions. Level needs to be checked with the engine at idle. Typically when it s low you will also get a delay in engaging in forward (reverse is not affected) then eventually if it gets too low you loose forward altogether
Like Pascal said, first make sure the oil level is right. Second, it depends on the pump, if it is a Hydreco, then yes it is adjustable. I never did it, am away from the manual so don't remember. I'd advise you call the nice folks at Acadian Transmission for advice on determining what you have and how to deal with it. They are the masters of al things Allison and related products. If the pump is bad, they are rebuildable. - Acadian Marine Transmission
Dont forget to check your screen, filter or any hose restrictions. I'm not an Alison jock, but the same theory of operation applies to all gears & clutches. Restrictions and air leaks will simply mess up a good clutch operation...
Brian Lemmon at Arcadian is a lot of help, even when you are on the other side of the world like I am. Hydrecos are quite easy to adjust. Pascal, Caltex and rccraps know the deal on these pumps and after 18 months of a lot of issues, I have learnt a bit as well. Check that screen. Check the oil while running.
Thank you for the replies Oil level is correct and screens are clean Will try the adjustment screw under the cap and report back Thanks again