> Matt Gaetke wrote:
> >
> > First off, when I adjust the distributor to the
> point where the
> > timing marks align properly, the engine all but dies
> (actually it usually
> > gives up on me). It runs best when the timing is well
> advanced (that's
> > anti-clockwise, right? say, 25 deg BTDC instead of 12 deg
> BTDC) of that
> > point. The other problem is that I can't run the engine at
> the 600 rpm
> > recommended in Haynes (at least that's the rpm listed with
> the 12 degrees),
> > see below.
>
Paul Hunt added:
> The distributor runs anti-clockwise, so to turning it
> clockwise advances
> the timing. If the timing is over-advanced but idling at the correct
> speed, then when you correct the timing the engine will likely stall,
> just screw in the idle screws a little by little as you go.
Back to Matt:
>
> > I know the carbs are not balanced/not adjusted
> properly, and the
> > engine sounds like it's running rich. Further evidence of this is a
> > considerable amount of dry, black carbon on the plugs (it
> doesn't look at
> > all oily). It also misses occasionally (timing?). Of
> course there is a
> > contradiction: the only way I seem to be able to keep the
> engine running at
> > low (<1800 rpm) is with about 1/2" of choke. I thought it
> could just be
> > that the idle screws were out too far and it wasn't getting
> enough gas
> > without the fast-idle cams engaged, but with the choke in
> (even giving it
> > more gas) it kills every time. Nothing I've tried yet lets
> me run it below
> > 1000 rpm.
> >
> > I don't know how to call this one. I've got a new
> condenser and new
> > points on order. The only part of the HT side that's not
> new is the coil.
> > Maybe I just need to start over from scratch. If so, how
> do I do this (step
> > by step to the smallest minutia :) )? How do I get the
> engine running at
> > 600 rpm to adjust the timing with the carbs messed up? I'd
> like to think
> > I'm not in over my head, but I could really use some
> advice. Anyone want to
> > take an aspiring mechanic under their wing? Thanks, guys.
More from Paul:
>
> Do the static adjustments on the valves, the ignition and the carbs
> first (if you think the latter are way out) then the dynamic timing
> adjustments then the dynamic carb adjustments. It still sounds like
> your idle screws are way out, the choke is just compensating for them,
> maybe worsening the mixture along the way. You should be able to
> compensate for huge amounts of wrong mixture with the idle screws.
I agree with Paul, and add one thing: It sounds like you also
have an intake leak.
I just chased this dragon myself a couple of weeks ago - turns out that
the gasket was leaking top and bottom on both intake ports. A good
cleaning and a new gasket fixed it up.
Dan Pockrus
'74 CBB
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