[sdilecce]

I have a 1966 Evinrude Lark VIII with selectric shift. My problem is my reverse slips badly. I can just barely use reverse to maneuver the boat wile idling. When I put it in forward from neutral there is strong clunk when it engages, but I cannot feel the reverse gear engage. The reverse used to work much better but seems to have gotten progressively worse. I thought the problem was from water getting in the gearcase, but changing some seals has solved that problem. I am only using Type C oil, and I change it often.

Are there any ideas as to what’s wrong? Any diagnosis work I can do short of pulling the gearcase apart? I have an Evinrude manual but the only thing I can see is checking the wiring which I assume is ok since it does reverse a little, and go into neutral. Could I have reversed the wiring ( + / - ) on the reverse when I changed the water pump impeller?

Thanks for any help or suggestions.

[R.Johnson]

First I would mark the prop hub to see if it is slipping. Than check all wire connection. Then the reverse hub, and spring.

[F_R]

Originally Posted by R.Johnson

First I would mark the prop hub to see if it is slipping. Than check all wire connection. Then the reverse hub, and spring.

Well, here is what I would do: I would ALWAYS begin with an electrical system check with a multimeter. Check the voltages at the blue and green wires at the motor. You should have battery voltage on the green wire with the forward button pushed and the same thing on the blue wire in reverse. Do not disconnect the wires when checking the voltages. And shift it a whole bunch of times to make sure it has good voltage every time.

WARNING, when messing around with the wires, never allow voltage to get to both wires at the same time while it is running. That will bust something---for instance maybe a reverse clutch spring (!!!). Or a forward clutch. Or a drive shaft.

Chances are great that you will have a low voltage on the blue one. That could be a wire corroded almost through somewhere, but more to be expected is a bad shift switch in the control. Extremely common, and expensive. The switches are hard to find too.

Tearing into the lower unit is the last thing to consider and then only after making darn sure the problem isn't electrical.

[sdilecce]

Originally Posted by F_R

Well, here is what I would do: I would ALWAYS begin with an electrical system check with a multimeter. Check the voltages at the blue and green wires at the motor. You should have battery voltage on the green wire with the forward button pushed and the same thing on the blue wire in reverse. Do not disconnect the wires when checking the voltages. And shift it a whole bunch of times to make sure it has good voltage every time.

WARNING, when messing around with the wires, never allow voltage to get to both wires at the same time while it is running. That will bust something---for instance maybe a reverse clutch spring (!!!). Or a forward clutch. Or a drive shaft.

Chances are great that you will have a low voltage on the blue one. That could be a wire corroded almost through somewhere, but more to be expected is a bad shift switch in the control. Extremely common, and expensive. The switches are hard to find too.

Tearing into the lower unit is the last thing to consider and then only after making darn sure the problem isn't electrical.

Thank you! I was getting 11.3 volts on the Green, and 6.4 volts on the Blue. Turns out there was 8 ohms of resistance on the Blue wire. The switch tested out ok so I'm running new wires from the control to the motor. I was ready to tear the gearcase apart.

I love this forum.