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![]() "markvictor" wrote in message oups.com... Jeff Rigby wrote: All correct except the shift engine kill switch SHOULD engage if there is any resistance disengaging from reverse or forward into neutral. I agree, but when the control cable and lower shift cable are in good condition, and adjusted correctly, the only way the clutch is "loaded", is essentially when underway above nominal idle,or excessive rpms prior to shifting, thus keeping tension on the clutch dogs. if the cables are out of adjustment, When trying to engage from neutral, if the rpm's are too high from premature throttle opening,the clutch will resist and the interrupt switch is actuated. When in gear,if the throttle is not closed and rhe RPM's are ,once again, higher than nominal idle speed, the clutch dogs resist disengagement, again tripping the interrupt switch... This resistance (if shift cable is good) comes from the dog gear not disengaging because the engine is running faster than the prop. The kill switch engages and the motor slows relative to the prop and the gear can disengage. If the engine is running, and the drive is engaged (in gear) It is absolutely impossible for the engine to EVER run slower than the propshaft OK, got me on terms, I should have said that there is pressure on the dog gear because the engine is turning the prop against the resistance of the water. So to be VERY specific, at idle speed there is resistance from the prop and it WANTS to turn slower but cant because it's in gear. Because of this the dog gear can not disengage so as you shift from either reverse or forward into neutral the kill switch momentarilly kills the ignition so that the engine is NOT putting drive pressure thru the gears on the prop and the drive gear disengages. .. A momentary spark interruption does not stop the engine. If you try to do full throttle direction changes, the interrupter should move to prevent damage, but in normal operation, the throttle hits the stop before the shift action proceeds, and the decelleration of the motor unloads the clutch dogs, and if the boat is moving, the flow of water over the prop actually aids in unloading it.... Correct; This kill switch is not necessarry if you are throttleing back from a plane and shift into neutral. The prop is trying to turn faster than the engine because the boat is coming down from speed and the water is turning the prop faster than the engine. It's also not necessary if your prop is out of the water because there is no load on the prop/dog gear Bottom line, the two causes of interrupter activation is attempting high load shifts, either from too rapid shifting at high rpm or misadjusted cables, or a simulated shift load caused by resistance from a damaged cable or possibly a heavily worn selector shaft bushing and seal. Correct wrote: When the boat is in the water and I switch the gear shift to neutral, it will NOT go into neutral most of the time...it just stays at the "no wake" speed but the shifter is in neutral. I have to shift it back and forth to get it to finally go to neutral. Any help would be greatly appreciated. The fact that the control handle is in the neutral position but the clutch is still engaged, is a pretty clear indication that there is not enough throw on the lower cable. This is often caused by the cable end on the interrupter bracket being positioned incorrectly in the slot on the cantilever.. On the v8's and v6's it should be at the bottom of the slot, but if memory serves me correctly, the 4 cyl. plate is inverted and the cable should be at the top of the slot. That will increase throw on the lower cable, and minimize or eliminate any unnecessary movement of the switch. If it was a bad cable, or high rpms, it would stall the motor while hunting back and forth to find neutral. I did have a bad shift cable that didn't cause symptoms like you'd expect, I had a shift cable problem where the kill switch was not being engaged and the outdrive would have problems going into and out of gear. This happened only in the morning and by warming up the engine (shift cable) the problem went away. Replacing the shift cable fixed this problem I also had a bad cable that manifested symptoms that were slightly unusual, the engine would stall when docking, upon further testing it was extreme outdrive angles while shifting that caused the stalling (the only time I used extreme angles (steering) while shifting was when I was docking the boat). Bending the shift cables by having the outdrive at extreme angles caused them to bind internally and hang causing the kill switch to stall the engine. Replacing the shift cable fixed this problem. trainfan1 wrote: Yes, it should... not entirely, just enough to shake the clutch dog off the gear No, it shouldn't, unless something is wrong...or you're shifting improperly, such as lock to lock.. Different adjustment. Of course it is, it's the throttle cable, but that can cause premature opening of the throttle plate, which in turn causes rpms to increase prior to gear engagement,which causes increased effort tho engage the clutch dogs,which should cause the interrupter. to actuate, which causes the boat to stall, etc etc,...But that's what's supposed to happen if the throttle opens too soon.... Jeff Rigby wrote: Probably the shifter cable is bad, your shifter kill switch is not engaging. That is when it would engage, if the cable was bad JIMinFL wrote: The shift bellow doesn't seal water out of the cable. If the bellow leaks the boat will take on water. A defective shift shaft bushing is the main cause for water intrusion into the shift cable You're absolutely right,,, |
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