TOPIC:

No pics?
Steve

Sorry about that - pics were too big I think.
Try again :

What's with #3 jet? Pics of plugs?
Steve
Steve

Not sure what you mean Steve?

"What's with #3 jet? Pics of plugs?"

1st attachment is of underside of carbs
2nd attachment is of the main jet fitted to the bleed pipe and the adjacent pilot jet (#17.5)
3rd attachment is a (blurry) pic showing where the pilot jet screws into the carb body
4th attachment is of the 4 pilot jets (#17.5)

Looks like the third jet on the right is damaged. I'd like to pics of the plugs.
Steve

Ok - only too happy to take some more pics.
I'll get some better ones of the jets and some of the plugs tonight.
(All plugs "read" the same - ie sooted up to the same extent - as you'll see.)

Any thoughts regarding the pilot jet 92064-1003 Vs 92064-1017?

Those are the correct jets for those carbs. Are you sure they haven't been drilled? If not the problem must elsewhere. Bad HT connections? Caps?
Steve

Have tried new jets (size 15) but with exactly the same results - all 4 plugs quickly soot up completely after running rich from start.
So maybe I've still got restrictions in the pilot air system ? - will use some carb cleaner and try another blow out.

Thought I'd eliminated the lecktrickery side - but maybe not???
Have tried 2 sets of plugs (NGK B8ES);
Coils are new (not OEM, but static checks with a DMM measure ok - 4.1 Ohm Rp and 23.5 K Ohm Rs)
No leakage primary to seconday
New NGK plug caps
Wiring from ignition switch to (new) main wiring loom checks out ok.
Good solid earth to coil mounting screws.

Have set up the static ignition timing per the service manual using multimeter to set dwell and gaps.
Haven't had a chance to use the timing light to "fine tune" this as idle and running is too unstable.
However, engine starts readily so is maybe pretty close?

Any more ideas?

Hook up your timing light and watch the flashes. If steady OK. If intermittent, there lies your problem, Check each spark plug lead.
Steve

This may well NOT be the answer -- But it's remotely possible that the enrichener circuits might be malfunctioning when supposedly closed and continuously allowing an overly rich mixture into the combustion chambers.






Perhaps a linkage issue with the choke plungers?
Or the plunger caps are deteriorated or missing?
Or for whatever reason the plungers are not fully closing?

Good Fortune!

Probably already done, but would assure pointed ends of pilot air screws are in good condition, and that the orifices are clean and clear where the pointed ends interact.

If stock air box, assure there's nothing under the seat such as a pair of gloves, shop rag or whatever that's blocking the air intake.
And of course that the air filter itself is fresh and clean and dry and freely flowing.

Good Fortune!

NGK plug caps likely have a built-in resistor.

Hopefully the spark plug wires are solid core non-resistor style, and not graphite resistor style.

Resistor caps plus resistor plug wires causes too much resistance in the secondary loop which results in weak spark.

And, is the timing advancer assembly clean and lubed and functioning properly?

Good Fortune!