In article 1CJGc.37696$Oq2.28736@attbi_s52,
"Tony Thomas" wrote:

If you hear more air from the bottom one then sounds like it may be not set
the same as the others. Reverify it is in sync.
As for the idle screw setting - not sure on this one. I would start at
about 1 1/2 and adjust from there.
Did you accidently adjust all 3? Could you not take a reading off of one of
the other carbs?

Yeah, I was a dumbass. My wife was distracting me and I wasn't thinking
and started backing out the screws. When I figured I had 'em out far
enough I tried to take off the airbox. Thats when I noticed the OTHER
screws on the backside of the airbox. I turned 'em in to 'stop' then
backed 'em out two full turns each. At this point I instructed my pesky
woman to go online to iBoat and order the Service Manual, which she
happily did. I await it's arrival.

The engine idles.

The bottom carb makes a fluttering sound, unlike the other two, no
matter how I adjust it. I'm afraid I'm hearing a valve or something
through the carb (and hose).


We took the 1984 Trophy out for our shakedown cruise on the Fourth.
It ran crappy at first, wouldn't get up on plane. But after a couple
minutes it suddenly "woke up" and hustled around fine. We cruised across
the lake just seeing the sights. I stopped to point out something, and
it ran crappy again after that. We limped back to the ramp and went
home. I'm assuming carb troubles because I know the boat sat for a year
before I bought it. Either that or gas vent troubles or one plug was
fouled. I dunno. I await that manual!

I would go ahead and tear down the carbs and give them a good cleaning.
There are no valves (reed valves but probably not the problem).


--
Tony
my boats at http://t.thomas.home.mchsi.com

"Jeepers" wrote in message
...
In article 1CJGc.37696$Oq2.28736@attbi_s52,
"Tony Thomas" wrote:

If you hear more air from the bottom one then sounds like it may be not
set
the same as the others. Reverify it is in sync.
As for the idle screw setting - not sure on this one. I would start at
about 1 1/2 and adjust from there.
Did you accidently adjust all 3? Could you not take a reading off of
one of
the other carbs?

Yeah, I was a dumbass. My wife was distracting me and I wasn't thinking
and started backing out the screws. When I figured I had 'em out far
enough I tried to take off the airbox. Thats when I noticed the OTHER
screws on the backside of the airbox. I turned 'em in to 'stop' then
backed 'em out two full turns each. At this point I instructed my pesky
woman to go online to iBoat and order the Service Manual, which she
happily did. I await it's arrival.

The engine idles.

The bottom carb makes a fluttering sound, unlike the other two, no
matter how I adjust it. I'm afraid I'm hearing a valve or something
through the carb (and hose).


We took the 1984 Trophy out for our shakedown cruise on the Fourth.
It ran crappy at first, wouldn't get up on plane. But after a couple
minutes it suddenly "woke up" and hustled around fine. We cruised across
the lake just seeing the sights. I stopped to point out something, and
it ran crappy again after that. We limped back to the ramp and went
home. I'm assuming carb troubles because I know the boat sat for a year
before I bought it. Either that or gas vent troubles or one plug was
fouled. I dunno. I await that manual!

Tony's procedure is good. Remember, the purpose in syncing the carbs is to
have each cylinder receiving the same amount of air for a given throttle
lever position. Assuming the carbs are equally clean and that the valve
mechanism (2 stroke or 4 stroke) has the same timing per cylinder, each
cylinder should deliver the same power if the carbs are in sync. Using
vacuum gauges, etc, isn't any better than visually aligning the butterflies
looking down the throats. Usually, one carb is designated the 'reference'
carb and the others are adjusted to match that one.


"Tony Thomas" wrote in message
news:rLzGc.17379$JR4.9020@attbi_s54...
Loosen all the linkage screws on the side of the carbs. With the throttle
at idle position, all the throttle plates should be down against the body.
Tighten all the linkage screws.
Now open the throttle to wide open and verify all throttle plates are
setting flat.
If one is out slightly - loosen and adjust to flat as the others.
Now back to neutral and verify all plates are the same.

Very simple on these engines.

--
Tony
my boats at http://t.thomas.home.mchsi.com

"Jeepers" wrote in message
...
Could someone have pity on me and point me to some kind of resource
describing how to sync three carbs.

I goofed and turned the screws on my Force 85's carbs instead of the
manifold mounting screws (long story, suffice it to say I wasn't paying
attention). I heard something about listening through a hose or
something once before, but I have no idea what I'd be listening for. I'm
handy with tools and have a workshop (I live on a ranch, it's a
necessity). I've worked on pletny of things from shredders to tractors
and Jeeps and lawn mowers, but none of them have 3 carbs!

In article ,
"C. J. Klingman" wrote:

Tony's procedure is good. Remember, the purpose in syncing the carbs is to
have each cylinder receiving the same amount of air for a given throttle
lever position. Assuming the carbs are equally clean and that the valve
mechanism (2 stroke or 4 stroke) has the same timing per cylinder, each
cylinder should deliver the same power if the carbs are in sync. Using
vacuum gauges, etc, isn't any better than visually aligning the butterflies
looking down the throats. Usually, one carb is designated the 'reference'
carb and the others are adjusted to match that one.

Thanks! I appreciate the info.

Mercury vacuum gauges, as used on multi cylinder motorcycles.

Its basically 4 rod vacuum gauges affixed side by side. You attach the line
to the provided vacuum ports on the carbs (behind the throttle plates), then
while running the engine, adjust the plate(s) so that all 3 gauges read the
same.

Adjust curb idle as needed...done.

Check you local motorcycle tool shop.

--
"Do or do not...there is no try"

Yoda- 1981
"Jeepers" wrote in message
...
Could someone have pity on me and point me to some kind of resource
describing how to sync three carbs.

I goofed and turned the screws on my Force 85's carbs instead of the
manifold mounting screws (long story, suffice it to say I wasn't paying
attention). I heard something about listening through a hose or
something once before, but I have no idea what I'd be listening for. I'm
handy with tools and have a workshop (I live on a ranch, it's a
necessity). I've worked on pletny of things from shredders to tractors
and Jeeps and lawn mowers, but none of them have 3 carbs!

In article ,
"Sam S." wrote:

Mercury vacuum gauges, as used on multi cylinder motorcycles.

Its basically 4 rod vacuum gauges affixed side by side. You attach the line
to the provided vacuum ports on the carbs (behind the throttle plates), then
while running the engine, adjust the plate(s) so that all 3 gauges read the
same.

Adjust curb idle as needed...done.

Check you local motorcycle tool shop.

Sounds easy enough! Thanks!

My Mercury shop manual says you simply set them up so all the throttle plates
are seated in the idle position and that they all start to open at the same
time. That was the way the dealer mechanic did it when he set them up too. I am
not sure there is a port to vacuum test them on a Merc.

In article ,
(Greg) wrote:

My Mercury shop manual says you simply set them up so all the throttle plates
are seated in the idle position and that they all start to open at the same
time. That was the way the dealer mechanic did it when he set them up too. I
am
not sure there is a port to vacuum test them on a Merc.

Now that you mention it I'm not sure either.

What I need to know is how far the screws (near the mouth) need to be
backed out.

I seem to remember the starting point on the idle screws was 1 1/4 out, then
you adjust from there. I have been on a 60 EFI 4 stroke for 2 years now but I
had the old 3 carb 2 stroke 75 for 12 years.