OMC gear shifting back to front

Gentlemen, both Stringer 3.8 OMC's (1981) are installed now, everything in working order.
However, the starboard helm remote lever shifts forward and engages reverse instead of forward and when shifted back it engages forwards - bit awkward for lining up the two throttle controls to go in the same direction!
After much thought, I can't see how altering the helm control lever or the cables/idler pulley in the shift converter housing would change the direction of pull.
However after looking at the service manual pictures of the shift housing in the gearbox, I don't really see how that could have been installed wrongly either. The cable end pucks are different sizes and so not interchangable. I don't want to lift the boat from the water and dismantle the outdrive if that could not be the problem . . .

Re: OMC gear shifting back to front

Did you replace the shift & throttle cables?
What control boxes are you using?

Re: OMC gear shifting back to front

Pete I replaced the twin shift and thottle cable running from the shift converter housing to the gearbox shift housing.

The helm control is the dual lever binnacle mount. Although I'm told there could be two sets of cable holes for this control lever to provide push or pull, I think there is only the one clevis pin mounting. The port and the starboard levers both push their cables out or back the same except the starboard engages the wrong gear.

Re: OMC gear shifting back to front

do you have one hydromechanical shift lower unit and one full mechanical shift lower unit?
The two designs shift opposite as i recall.

the absence or presence of the rectangular zinc anode behind the idle exhaust relief in the lower housing tells if they are the same or not.
here's a pic of the full mech for reference

Re: OMC gear shifting back to front

I think you better look at the boxes again.
Is there any chance you got a left handed prop on that side?

Re: OMC gear shifting back to front

Pete they are both right hand drive
- HOWEVER - Howard you are absolutely correct, the starboard gearbox (the one shifting wrong) has an anode whereas the port does not.
I could not remember which gearbox, but one had the power assist shift servo and the other was a straightforword pull/push mechanism.
What have I done wrong sir?

ps on my service manual p.7-9 showing Vertical Drive Disassembly, my left side picture does not show that anode - older book?!

Re: OMC gear shifting back to front

yes, later book shown in that pic. the mechanical lower unit was introduced in 82 or 83.

When you connect a mechanical lower cable to the hydromech shift converter box, FWD becomes REV as the cable to the lower unit works backwards from the hydro.

you will also have difficulty shifting the mechanical unit to neutral in the water as you have no ESA module.
Electronic Shift Assist is needed to shift out of gear on mechanical lowers. Forcing it will stretch and or break the cable eventually.

Re: OMC gear shifting back to front

Possibly the starboard gearbox has been replaced with the later type -the boat was made in 1981.

It is this starboard sterndrive with the anode, which you say will have the simple mechanical change instead of the hydro assist - which is shifting the wrong way.
Now I am confused. You say the hydromech (assist?) system would be connected wrongly from the shift converter box (mounted on the intermediate box). But that is the older port gearbox (no anode) which changes correctly.

That port side shift converter box has a longer shift arm; the later starboard converter box has a shorter shift arm with an electrical cut out switch. Mind you - I might not have replaced them on the side they were fitted originally, not knowing any better! But, although I have not had the chance to test the gear engagement away from the pontoon, both side gearboxes engage and disengage fwd and rev smoothly at about 6 - 700 rpm.

I did renew both gearbox shift cables. Are you saying the cable is different for the mechanical change to the hydro assist. Or could the shift converter housing be different. I have not yet looked inside the port housing with the longer arm/ no electric switch to check any difference yet.
Andy

Re: OMC gear shifting back to front

cable is different, converter box is different. everything changed in 1982/83
those hydromechanical servos were failing so OMC changed the design and quit servicing the hydro lowers. The dealer repair for a failed servo was to replace the lower with a mechanical lower unit, adding an ESA system, amd changing the converter box

Re: OMC gear shifting back to front

Righto Howard, I shall hotfoot to the boat this afternoon and check those shift converter housings. Hopefully I have replaced them the wrong way around and they only need changing back.

There is a shift converter housing fitted to the later port engine ( which shifts wrong) with Electronic Shift Assist already I think. It has a shorter lever arm fitted with an electric switch. There is a white plastic semi circle with stops to control this switch.

Is there a difference between an ESA and an Overstroke Switch?

What I am now concerned about is a difference between the original gearbox cable and a later one. I found it very difficult to find new cables, and there does not appear to any reference to a different cable for the later shift.