What is this valve for???
 

Hello,
this part is on top of the Velvet drive. It turns as you go FWD or REV with the shifter. Looks like sombody before me made a decision they didn't need it hooked up to what ever it was and capped it off. I'm just wondering what it was for, can't find a name for it or see it on parts list. Do you know?

Thanks.

Re: What is this valve for???
 

That is some old stuff there my friend. Those were found on early alpha drives and trs drives. The trim system use to work through that.

It looks like they have bypassed it if there are no trim hoses going to it and your trim works. Very, very old technology.

John S. :D

Re: What is this valve for???
 

I have these on my BW trans also and they are startin to leak what is there purpose??? anyone know?

Re: What is this valve for???
 

They are called reverse lockout valves, if the trim is up it won't shift into reverse??? I have bypassed them in the past with good success when found leaking. Part has been discontinued from Merc.

Re: What is this valve for???
 

I have them also. 1982 Excalibur Hawk 40

Re: What is this valve for???
 

Yes they are reverse lock valves, they keep the drive from kicking up when you put it in reverse. The new style Oildyne pumps do not need/use them. The idea was the pressure relief on the down side of the pump was set low enough to allow the drive to kick up easily if you run aground or hit an obstruction. However the reverse thrust from the prop would also lift the drive hence the valve.

Re: What is this valve for???
 

Thanks for the info....old technology that even looks old. I figured it was probably unneeded. This boat needs a lot of mechanical clean up