Take a look and listen -- see if you can help me diagnose the problem!

Grumpy Bear

Grumpy Bear

Seaman
Joined
Aug 23, 2014
Messages
58
Thanks ahead of time! Couple of short video clips to watch/listen to if you can. Motor is "warm" and warm-up throttle is now all the way off. Choke is off.

So, I have:

- Link & synced (at least 3 times to make sure)
- Carbs are clean and set to spec
- Turned out the carb idle screws about 1.25 turns or so (I've tried 1.5 and the result is basically the same)
- Checked compression, and it's perfect
- Made sure every plug wire is getting consistent spark and tested every spark plug
- Does not APPEAR to be any water in any cylinders. Some fouling but its black oil (this is a break in, so there's more oil in the gas to Merc's specs. Idling can cause some oily build up from what I understand). When I rebuilt it, I was very careful to clean off all gasket material, put on new, and tighten to spec, middle to out.

But it still runs at high idle and pretty rough as you can see/hear. If I put her in gear (which I really shouldn't do at 1200 RPMs) she still hesitates and dies. What do I adjust next??

First clip:
 
E

emckelvy

Commander
Joined
Jan 16, 2004
Messages
2,506
Yeah, it's just a wee bit rough! If you have a timing lite or firing indicator, check the spark quality in each cylinder while it's running. If you find a sketchy spark on one or more cylinders, you might want to pull the distributor and check the cap for crud. Sometimes a dirty cap can cause crossfire and poor operation.

If you have a DVA adapter (or pick up a cheap one like this: http://www.usatoolwarehouse.com/usatoolwarehouse/ESI-640.html ) you can check switchbox & coil voltages and that might tell you something.

Check the CDI Electronics ignition troubleshooting info:

http://issuu.com/cdielectronics/doc...t.xml&backgroundColor=000000&showFlipBtn=true

Your ignition system is called a "Lightning Energizer" with a self-powered breakerless "magneto", an upgrade from the old-style magneto/points ign.

It also sounds like it needs more timing, it might be time to quadruple-check the initial timing belt alignment. Check the degree of spark advance (or retard) with a timing lite at idle. Some motors just like more timing than others to idle correctly and you might need to advance timing one belt tooth. In that case, it'll throw off your max spark timing and require readjustment.

Another thing to try is a "cylinder drop test". Pull a plug wire, stick an extra plug in the boot & ground it (or use a spark tester, etc) and see if that cylinder was actually kicking & carrying its share of the load. If you find a "dead" cylinder that makes no difference when the wire is pulled, it's an area to concentrate on.

Last thought, you can block off one carb or the other with your fingers or a cloth shop rag (no paper towels!), that'll tell you a lot about fuel feed to each pair of cylinders.

HTH, let us know what you find..........ed
 
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