User Tag List

Page 2 of 2 FirstFirst 1 2
Results 16 to 22 of 22
  1. #16
    Join Date
    Dec 2007
    Location
    Puget Sound, WA
    Posts
    19,026
    Thanks (Given)
    47
    Thanks (Received)
    435
    Likes (Given)
    1191
    Likes (Received)
    7459
    Mentioned
    1 Post(s)
    Tagged
    1 Thread(s)
    Quote Originally Posted by SDP View Post
    The new, higher idle, after getting those tiny orifices cleared in the throttle body, does not audibly sound too high to me. But it's about 300 or 400 rpms higher than it was when those orifices were clogged, so it raised an eyebrow.
    It's been pretty cold here lately, 20 miles north of Milwaukee, Wisconsin. But Friday is supposed to be 56 degrees, so I'll need to go to the Wolf River for some fishing. I just acquired this boat in October, and haven't had much of a chance to fish from it yet. (it's a 1993 Champion 176 Fish&Ski.)
    My old Ski (snow) club did the Wolf River White Water rafting! And many times with friends (from Northern Ill us) camped out some sand bar Wisconsin river. W/E's spent the Fox Chain, Ill. Great people, great food, great times!

  2. #17
    Join Date
    Dec 2012
    Location
    Moses Lake, Wa.
    Posts
    156
    Thanks (Given)
    1
    Thanks (Received)
    3
    Likes (Given)
    0
    Likes (Received)
    3
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Shift interrupter works as follows. It takes a fair amount of effort to make a big horsepower motor come out of gear. Both fwd and reverse. More so out of fwd because you're going WOT in fwd compared to reverse. . One reason for the extra effort is the "back-cut" of the dogs on the shifter/clutch dog and also on the matching dogs on the gears. And, the more hp, the more torque that is generated as the engine revs faster. That torque can be held gear against gear (dog against dog???) even when you come back off throttle. So, to minimize the effort to get those gears apart/break the torque. OMC decided to hesitate the ignition momentarily, as you shift the control box into neutrel. It happens coming out of fwd AND reverse. The shift interrupter mechanism is on the stb side of the shift linkage on the 'end" of the horizontal shaft at the fwd lower part of the block. It has 2 wires, blk=ground and blk/yellow= kill circuit to the power pack. This circuit is provided with a diode so that the ignition is only activated to the stb side ignition spark and not the port side. Some engines had two packs and only the stbd one was effected. As you shift out of gear, the switch rocks and grounds out the intrernals of the pack and hense, no spark to the three stbd coils. The engine continues to run but "stumbles' cause 3 of 6 cylinders are not firing. This happens fairly quickly and in no time you are in neutrel, the switch reverts back to "normal" position, the switch goes "open" and the engine now idles in neutrel back on all 6 cylinders. OMC had a fair amount of issues early on when they introduded this system but that was a few years earlier. Hopes this helps.
    Last edited by King Dad; 11-22-2017 at 09:32 PM.

  3. Likes powerabout liked this post
  4. #18
    Join Date
    Oct 2017
    Location
    Wisconsin
    Posts
    29
    Thanks (Given)
    0
    Thanks (Received)
    0
    Likes (Given)
    0
    Likes (Received)
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    So basically, the design is to momentarily kill the engine?
    If the interrupter switch is bad, what is the symptom?

  5. #19
    Join Date
    Sep 2006
    Location
    Minnesota
    Posts
    5,543
    Thanks (Given)
    0
    Thanks (Received)
    35
    Likes (Given)
    0
    Likes (Received)
    96
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by SDP View Post
    So basically, the design is to momentarily kill the engine?
    If the interrupter switch is bad, what is the symptom?
    Close. It momentarily kills 1/2 the engine. If it fails to interrupt, shift out of gear to neutral is difficult. If it fails to stop interrupting, engine idles on 3 cylinders, or dies.
    To fish or not to fish? What a STUPID question.

  6. #20
    Join Date
    Oct 2017
    Location
    Wisconsin
    Posts
    29
    Thanks (Given)
    0
    Thanks (Received)
    0
    Likes (Given)
    0
    Likes (Received)
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by j_martin View Post
    Close. It momentarily kills 1/2 the engine. If it fails to interrupt, shift out of gear to neutral is difficult. If it fails to stop interrupting, engine idles on 3 cylinders, or dies.
    That makes sense, thanks.

  7. #21
    Join Date
    Oct 2017
    Location
    Wisconsin
    Posts
    29
    Thanks (Given)
    0
    Thanks (Received)
    0
    Likes (Given)
    0
    Likes (Received)
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Hello,
    I thought I'd come back and report what the issue finally appears to have been all along.
    There is one screw on the spark lever. It wouldn't get a bite anymore in the plastic hole it sits in. This was causing the roller on the end of the spark lever to be about an inch away from the throttle cam after shifting back to neutral from foward. The roller needs to be just touching the throttle cam in neutral. But with that stripped screw, the spark lever could not be tightened to keep the roller where it needed to be. Hopefully this might help someone with stalling after shifting.
    The 1-inch travel of the roller befoe touching the throttle cam was causing the engine to stall after shifting.Click image for larger version. 

Name:	20180514_180213 - Edited.jpg 
Views:	11 
Size:	291.9 KB 
ID:	407338

  8. #22
    Join Date
    Mar 2008
    Location
    South Africa
    Posts
    575
    Thanks (Given)
    0
    Thanks (Received)
    7
    Likes (Given)
    0
    Likes (Received)
    30
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Another thing that I have found with those plastic carbs.
    There is a plate on the starboard side held on with 5 screws.
    This seems to be the idle circuit.
    I have noticed on quite a few engines that you can get an air leak past the gasket.
    I take the plate off on these engines and put a bit of a curve in the plate and re-assemble
    This stops the air leak, which would make it run leaner at idle

Page 2 of 2 FirstFirst 1 2

Similar Threads

  1. Mercury Tech: Ideas on Mercruiser 260, 1980 - Good idle under load, high in neutral, and shift prob
    By CanyonDoug in forum Technical Discussion
    Replies: 79
    Last Post: 05-03-2017, 07:32 PM
  2. Neutral safety????
    By need1morefoot in forum Technical Discussion
    Replies: 0
    Last Post: 06-19-2012, 08:55 AM
  3. Rpm's rev to 3k at neutral??
    By play2win in forum Technical Discussion
    Replies: 26
    Last Post: 08-09-2011, 01:42 PM
  4. Neutral cut off switch
    By FlCheckmate in forum Electronics, Audio Systems, and Wiring
    Replies: 0
    Last Post: 08-19-2006, 06:45 PM
  5. Revving in neutral?
    By Techno in forum Technical Discussion
    Replies: 2
    Last Post: 07-23-2002, 09:45 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Chris Carson's Marine