- This topic has 1 reply, 1 voice, and was last updated 2 days ago by
.
-
The first “boat run” a couple of days ago,
on this Merc I went through last winter was
mostly positive.
The motor went “Lickety-Split” all through
the “wind up”, but did not want to idle.
Then there was the disturbing rattle at times.https://youtu.be/b2Eta2CwJvA?si=3PgZaTajkszscNBA
Yesterday, I removed the rewind and installed
a Champion rope sheave. Happy to say the annoying
rattle went away.
As far as the idle, things went down-hill further.
Now at lower rpms, before it dies, it’s dropping a cylinder.
If you catch it in time before it dies, the cylinder picks up.
I was all over the place on the low-speed adjustment, but
couldn’t remedy the issue.I started digging into possibilities. I could have started with
the easiest, and changed spark plugs, but what fun would that be.
Ordered some plugs to replace the Champion J6’s.
Correct plug shows as J7J back in the day.
Ordered the modern replacement DJ7J, I think.
Magneto off- Points clean, no obvious signs of issues.
Hooked up the magneto to the Stevens tester. Both (OMC) coils
are firing steady around 2 amps. No signs of arcing when probing
with the tester.
Tested the new top crankcase seal with motor oil, and there was “zero”
bubbles while turning over the crankshaft.
Carburetor now off, and that’s today’s mission to check the low speed
circuit.
Prepare to be boarded!
Went through the ignition and carb again today.
I noticed that the throttle plate was a little wonky
on the shaft, and not shutting tight in the bore
between the two little low speed circuit fuel feeds.
Some re-adjusting and a touch of loc-Tite seemed to
improve the fit.
I’m not sure I’ve seen a throttle plate / butterfly, that
doesn’t go all the way to the bottom of the bore.
Is this original on the AJ40A carb?Also noted that the low-speed jet tube didn’t have one
of those little red fiber washers on it. I’m not sure if
it’s supposed to on this carb, but I added one.
The carb bore in the block isn’t round, and is slightly
bigger that the round bore in the carb, which seems
stupid to me, not to mention a quandary when making
a new gasket!
I put the magneto back on, and went to sync the points
with my buzz box and a TDC dial indicator.
The bottom cylinder set of points was not making good
contact to “set off” my buzz box.
I re-worked the points trying to get the two “point halves”
to close squarely, but only slightly improved them.
The were only making a tiny contact area, and slightly
etched in that area.
Will have to see if I can get some new ones.
The points in it are REPCO brand, so I presume not original?The after-market OMC coils and condensers I used, had huge
terminal ends on them, making a good connection to the point
sets a challenge. I should have done this the first time, but I
removed said terminals and soldered some dainty ones on.
I only put back together necessities needed to make it actually run,
in case it still won’t idle or keeps dropping a cylinder.
I haven’t got around to looking at the rattle-trap rewind yet anyway.
Hopefully tomorrow some time I can barrel test again to see
if I made any improvements.Prepare to be boarded!
- You must be logged in to reply to this topic.