John,
The broken rod theory only fits up to a point. Ker-thunk on rotation and
smashed electrode are pretty good smoking guns..but.
The less than adrupt stoppage with oddball sound prior to losing that one
cylinder seems out of line with a broken rod.
But maybe it still isn't broken completely in half or didn't break all at
once.
If only part of the rod big end opened up and the piston started kissing the
plug more and more that might explain the odd noises before loss of that
cylinder. Since actual ignition firing is well before TDC, a mechanical
"kiss" would be spaced after a firing.
Chuck
From: "John Vriesinga" <[EMAIL PROTECTED]>
Reply-To: [email protected]
To: <[email protected]>
Subject: Re: [F500] Help I don't know what to do anymore
Date: Sun, 24 Sep 2006 22:35:24 -0400
Faulty electronics also doesn't appear to explain why you melted one
electrode and the other is perfect, or is it?
Both plugs looked beautiful prior to the last run. I noticed that the
engine started to sound ratty, like it was firing more often than it was
supposed to. There was the steady drone of the usual firing but in between
there was a ragged sounding firing tha sounded like it was limited to one
cylinder. Then it suddenly took to firing on one cylinder only ( when the
electrodes fused toegether I imagine) and finally it shut down completely.
What is your timing set at? At least tell us where you are in the stator
slots. If the stator is rotated as far as it wil go CCW that is max
advance. Estimate the gap to the end of the CCW travel.(looking from mag
end of motor.)
Then, what is your jetting? Fuel you are using?
Using Sunoco 94 through 2 36mm Mikuni with 240 jets.
Dual port fuel pump with a very weak or intermittent output to one
cylinder?
I've got the regular old mechanical pump on. I disconnected the electric a
while ago thinking that it might be overfilling the carbs.
Now that might possibly be temperature dependent.
Crankcase pulse pump giving up when motor is hot and more fuel always left
in one bowl then other. Then cornering force takes that low fuel level
cylinder totally lean first?
-kinda reaching here :->
Sounds to me like it's time for a completely new engine.
JV
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