First I must appologize for a lack of info, as I'm doing this 2nd hand
at this point, helping a cousin off on Marthas Vineyard.

He repowered a 30 footer single screw with a mercuriser V8 (to be
honest not even 100% sure its all a Mercruiser but parts match so I'm
going with that).

I was going to MV in July and he mentioned he was having carburetor
problems. Since it has a Quadrajet (termed by some as Quadrabog),
which I am familiar with, I said I'd pick up a rebuild kit on the
mainland, help rebuild while I was there, piece of cake.

We did just that, of course not all parts matched like the float
needle seat and ball, but the old ones were in good shape and
reusable as were all the jets and seats. The gaskets matched which
was the most important part. Tthe carb was very very full of gunk
especially in the fuel bowl. Cleaned that and all the passages, and
while doing some googling in the groups found that the bottom plugs
give problems too, so resealed those as well. Put it all together put
it on, ran like a charm, went out into Vineyard Sound pulled a lobster
pot so he could show me the hydraulics returned to port - success.

Early (for a vacationer) the next morning he called, and said the boat
died. So for the first time I went to see for myself. Of course it
wouldn't do it then. So we made arrangements to meet the next morning
around 10 so I'd be there for the first firing. Started right up, and
I'm thinking he's jinxed, and then right about the time you would be
comfortable with pulling out, she died - bam. That was not my idea of
carbureter problems.

It turns out he has replaced the alternator with a single wire one,
and thus a new wire was required there. He replaced the distributor
with an electronic Peako (sp) to be honest I've forgotten the name,
but it's a common replacement as I recall it.

Well we put some meters on ignition, batteries, coil, circuit breaker,
but didn't find anything conclusive. We even were able to recreate
the problem once more that day and twice the next day, but no joy in
trouble shooting it.

Had to head back to the mainland but kept googling around and found
that the "pruple" wire needed to be up to spec. It wasn't clear to me
that this is a resistence wire and I haven't resolved that issue. He
said he checked the resistence and it seemed fine to him.

The way it quits has to be electrical. None of that gas starvation
sound, just wham dead, doesn't even diesel a little.

One part that he is loath to touch and I am suspicious of but can't
find anything bad about is the circuit breaker on the back of the
engine. One would think this would just pop or not. But I have my
suspicions that when it's damp in the morning on the Vineyard, so
moisture is getting in there and wreaking some kind of havoc once the
alternator has charged up the batteries and starts to send more juice
back there. Once the moisture burns off, it then works fine. But I
can find nothing on this part that would make it worth while to swap
out. Nor can I find a wiring diagram to indicate what it is really
doing so I can tell him "just go get a 50 amp fuse block and wire
around it and see what happens". If I recall correctly, we even had a
meter on that when it died once, but it happens so fast, there's a
good chance we could have missed a spike especially since we were just
looking for the presence of voltage and not looking at the amps
comming in. Since that circuit breaker costs about $60 to replace,
he's not going to run out and get one on my gut feeling!

Any thoughts on this?

Note because this is a retrofit, there are none of the typical
neutral switches to deal with, nor can I tell there there is anything
other than a "normal" feed coming out of the ignition switch (again a
mongrel item). By normal I mean it is not a special resistance wire.

Thanks for putting up with the long note and for any help you can
give.

email is goingjag at yahoo dot com - sorry I'm sick of spambots