Throttle Position Sensor.

[chicasau]

Good day.

My first post so let me introduce myself. My name is Jim. Just picked up a 1988 21 foot sorrento. Boating on Lake Erie out of the Port Clinton area.

The boat seems to be very sound except for one problem.

After the boat is in gear it is difficult to get it to return to neutral. From the initial investigation it sounds as though this may be a bad throttle position sensor (shift interupt. . Is this something than can be done by someone with decent mechanical skills or should it be left to professionals.

Second question is am I on the wrong path? Is there an adjustment that should be made to the cables?

Thanks for any input.

 

[Knotty Buoy]

This is a common problem and generally easily fixed. First thing to do is check your idle speed is within spec for the engine. If it's idling to hard it will be difficult to pull out of gear. The micro-switch that you're refering to senses the load on the gearshift mechanism and dosn't really have anything to do with the throttle position.
the assembly that it's mounted on is more or less the same on all Mercruisers and OMC engines (Volvo uses a different kind of clutch arrangement and the ones I've seen don't have anything similar.) If you let me know what engine's in the boat I'll tell you where the switch is and how to test it...........it's not difficult. Again, adjusting it tends to be trial and error although I got that frustrated with mine being so tempremental that I stripped it off and "re-profiled the notch" to make it a bit more reliable.

 

[chicasau]

Thanks for the reply.

I have looked at the assembly. It is on a merc 5.7.

This is what I am considering. Checking the cable to be sure it is line with the specifications and the switch. And checking the switch.

I don't think it is the switch and the cables need adjustment. Should I do this or leave it to a pro.

 

[Knotty Buoy]

Couple of quick checks..if it's the switch you'll find it goes in and out of gear ok when it's running with a hose and muffs on the hard. (It'll will make a bit of a clang as it goes in and out of gear, they all do.) Don't rev it hard like this and take care with the obvious dangers. The other thing to try is operating the microswitch by hand with the engine idling, it should stall. Leave messing about with cable adjustments till last as they should be ok unless some one has been playing around with them or changed a cable.