Re: T2Stroke

[Don]

Well, first, I’m guessing WOT RPM is down because that cam pick up timing adjustment looks so far off the throttle valves are not opening fully. Very easy to check out though….Simply advance the throttle arm to its WOT position, it will be hitting a small stop nut on the block. Now have a look at the roll pins in the throttle plates. The roll pins should be in the vertical position, parallel to the driveshaft, make sure the engine is perpendicular to the ground so you are not deceived…If the roll pins are way off in either direction, the throttle plates are not opening fully….
OK, so the quick and easy sync technique did not work out well, although you said it ran/idled OK for a bit….
The steps we skipped should be addressed, it is just hard for me to advise how to do this without the TDC tool. Like I say, the flywheel key could be sheared, which would affect idle and pick up timing, unfortunately this problem would not show up on a timing light. Needless to say, you could remove the flywheel to check this out, but that is tough without the OMC puller tool. Please don’t attempt to remove the flywheel with a conventional harmonic balancer puller tool, there is a good chance you will break bolts and get hurt, but the flywheel will still be in place. For now, just have a look at the flywheel nut, does it look like someone has been in there messing with it? If so, perhaps they didn’t get the nut properly retorqued, which would cause the key to shear.
The other issue these engines suffered from is a terrible cost savings method that should never have occurred. The inner hub magnets used to be cast in place….Some genius then decided this inner rim magnet could be "glued in place" on the flywheel hub (aka big cost savings). Needless to say, it is not uncommon for the glued magnet to get loose. Symptoms of this could be just about anything, including a poor/erratic idle along with a lack of WOT power (due to retarded timing). Now, this symptom will show up on a timing light. Either you will see the timing jumping around for any one given throttle position, or you would not be able to properly set the pick up timing….The only reason I’m thinking of these issues is because that throttle arm adjustment seems so far out of whack, perhaps in an effort to compensate for unknown flywheel issues. I’m not sure when the glued in place rim magnets went into production, perhaps Dan will know if your 88 model might be affected.
I’m trying to think of something simple that could be used in place of the conventional TDC tool…The only thing I can come up with is a spark plug with real long threads that might hit the piston once threaded all the way in, perhaps something off a car engine. In the mean time, perhaps someone can post the instructions for checking TDC from the manual, I won’t be home for a few days to do this. In the meantime, try to find a long reach spark plug that will hit the piston dome when #1 piston is all the way up. Please be very careful doing this, remove all the other plugs first, disconnect the battery, and don’t jam the plug into the piston dome. Simply turn the flywheel a bit past TDC on the number one cylinder grid, then thread the long reach plug in there to see if it will hit the piston…Please do you best to avoid turning the flywheel backwards more than a few degrees. Turning the flywheel backwards excessively could flop the impeller blades over in the wrong direction and create a whole new issue for you/us…
Hopefully, we can post the written/illustrated TDC instructions for you, trying to write it out without a diagram will be near impossible. Ideally, would love to find a long reach plug that will hit the piston at least 20 degrees BTDC…
Tell me more about when the engine idled "OK"….Did it idle OK when you first start it, then idle crappy after you backed it down of WOT? There is the remote possibility that the throttle linkage is stiff. I have seen this condition once on a salt water motor…The engine idled OK when you started it and ran fine when run up to WOT. But, when you slowed it down it bucked sneezed and stalled. But, it then started and ran fine again once you returned the throttle position to idle neutral. This was because the outer throttle arm was corroded and stiff on the inner arm causing the timing to be retarded first before the throttle plates were closed down when decelerating….I am ashamed to admit I threw some ignition parts at this relatively simple problem before I plugged in the dumb !@@ light and figured it out. Needless to say, the new ignition parts went back in the box and my boss gave me a well deserved kick in the butt. I guess there is an easy way to see if this is an issue. Simply disconnect the throttle cable, then push the throttle arm up to WOT…Now release it, the big spring inside should pull the outer arm back until it lines up with the inner arm…If the throttle arm just stays in place when you release it, then you have a problem…Again, 99 percent sure this is not the issue on your fresh water engine, but who knows. But again, the symptom would be that the engine would start up and idle OK, and run up to WOT with no issues. But, it would sneeze and cough/probably stall when slowly decelerated from WOT back down to slower speeds.
OK, the six recirc valves are not hard to check, but you will need one of those clear plastic "monojet" syringes with the tiny pointed tip the will fit inside the small diameter recirc hoses. The recirc valves will be tough to find with the carbs in place, but you can do it…There are six small brass (probably painted black) threaded in nipple, two under each carb. These are simple check valves, you should be able to draw fuel/air out of them, but you should not be able to push the fuel/air back through the valves.
I wish you could post a video of the engine idling, when it is idling OK, and then again when it is not.
Feel free to chime in Dan or others, just don’t want to lead this poor fellow down the wrong path…