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GOT MY BOAT UP N RUNNING

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birdy916

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"THANKS GUYS FOR ALL YOUR HELP

"THANKS GUYS FOR ALL YOUR HELP...I PICKED UP A USED IGNITION MODULE FROM A LOCAL GUY, HOOKED UP ALL THE WIRES AND CRANKED IT AND IT STARTED RIGHT UP...BEFORE I EVEN STARTED IT, I TEST IT TO SEE IF THERE WAS SPARK BEFORE HOOKING IT UP TO THE DISTRIBUTOR AND THERE WAS.

BUT I HAVE ANOTHER QUESTION...SOMETIMES MY CARB WOULD CHOKE AS I GIVE IT MORE THROTTLE, DOES THE WATER PRESSURE OF THE EAR MUFF AND THE BOAT ACTUALLY BEING IN THE WATER MAKE ANY DIFFERENCE?? CAUSE BEFORE I HAD IT RUNNING, GIVING IT GAS WITH THE EAR MUFF WAS FINE IN NEUTRAL OR IN GEAR BUT AS I TAKE THE BOAT OUT THE WATER AND DROP IT IN THE RIVER OR LAKE, IT'LL USUALLY CHOKE IF I GIVE IT A LOT OF GAS...BUT SINCE I JUS GOT THE BOAT RUNNING AGAIN, I WONT KNOW IF IT STILL DOES THAT OR NOT TIL I TAKE IT OUT TOMORROW...THANKS FOR READING GUYS!!"
 
"Birdy:

Good to hear it&#39

"Birdy:

Good to hear it's running. The reason it doesn't stumble when on a hose is there is not a load on the prop as there would be in the water. Adjust the timing to specs. Next adjust your idle mixture per the manual in neutral. Now w/the boat in the water tied to a dock securely, put it in forward or reverse and adjust the idle speed to specs. If it still stumbles, turn the mixture screw 1/4 turn to rich."
 
"THANK. O, THATS WAT I THOUGHT

"THANK. O, THATS WAT I THOUGHT TOO. DO U KNOW WHERE I CAN GET OR LOOK AT THE MANUAL ON HOW TO ADJUST IT??
ALSO WAT IS THE CRUISING RPM FOR THE 305 AND WAT IS THE MAX??"
 
"timing is 8 deg. BTDC
idle R

"timing is 8 deg. BTDC
idle RPMs is 650 - 700
WOT RPMs are 3800 - 4200 for some models; what's yours? Other models are 4200 - 4600
cruising RPMs...my guess is 3,000 - 3,500 RPMs or what feels right to you."
 
"THANKS...

WELL I TOOK THE

"THANKS...

WELL I TOOK THE BOAT OUT TO THE RIVER TONITE AND IT RAN LIKE CRAP...RUNS FINE WITH THE MUFF BUT WEN IN THE WATER, PUT IT IN GEAR WITH LIGHT THROTTLE AND IT RUNS FINE BUT AS I GO A LITTLE HIGHER...IT'LL START TO CHOKE AND DIE...MESSED AROUND WITH BOTH THE SCREWS AND STILL NO LUCK...THIS SUCKS!! LOLZ"
 
"Birdy:

You started a new

"Birdy:

You started a new thread so tell us what is your 305 engine year?

There seems to be a fuel related problem. Next time out, loosen the fuel fill cap a little so it could allow air into the tank and see if it runs better.

What color do the spark plugs look like; more tan or black? Concerning the fuel system, what maintenance or repairs have been done?"
 
"I'M NOT SURE WAT YEAR MOT

"I'M NOT SURE WAT YEAR MOTOR IT IS. THE BOAT IS A 79. ITS NOT THE ORIGINAL MOTOR EITHER. I'D GIVE U THE SERIAL # BUT ITS TOO FADED TO TELL. I GUESS I'LL HAVE TO TRY THAT WEN I TAKE IT OUT AGAIN.

WELL I TOOK SPARK PLUG #2 OUT AND IT LOOKS BLACK SO I'M GONNA HAVE TO CHANGE THEM AGAIN SOON.

AS TO THE FUEL SYSTEM. I'VE SUCKED OUT ALL THE OLD GAS IN THE GAS TANK AND PUMPED IN ALL NEW GAS. I'VE ALSO CHANGED THE FUEL FILTER. COULD MY CARB B BAD MAYBE?? WEN I GIVE IT GAS, IT SPITS OUT GOOD AMOUNT OF GAS TO IT. ITS JUS THAT WEN ADJUSTING THE SCREWS ON THE CARB, IT STILL SEEMS TO CHOKE WITH JUS LITTLE GAS."
 
"There is a filter in the fuel

"There is a filter in the fuel pump and a filter screen in the fuel inlet at the carb. Black plugs means the carb is too rich. Does the choke function properly? Is it electric? The choke plate should be nearly closed when the engine is cold and open up slowly as the engine warms. If it doesn't open all the way when the engine is hot, then it needs to be adjusted or replaced.

The choke should feel warm if it has wires on it. If it is not elec. then the heat source comes from the exhaust thru the intake manif. crossover. They will get plugged up and have to be cleaned. If it is not electric, then change it to an electric one."
 
Sorry Guy
Thought I was follo

Sorry Guy
Thought I was following the appropriate post. My question referred to your last comment to Bridy Yang about changing to an electric choke. Based on your recommendation I whould like to know if you knew of a kit to change to an electric choke on a 5.7L 350 with Rochester Quadrajet. Guess I should have given you a little more info. I have a 1989 Slickcraft with a MCM 5.7L Mercruiser and a 4MC Rochester carbureture Mercury No. 1347-9662. This is a project boat and I have never taken on such a large project. The engine is a remanufactured long block. I had to change to an after-market intake manifold and the relationship of the carb to the manifold required some adjustment of the choke rod. If there is an advanatage to changing to an electric choke then I would consider doing it.
Sorry for the confusion and thanks for the quick response. Also see my new post.
Bob
 
"The site below shows a blowup

"The site below shows a blowup of your carb. I don't see a throttle plate side mounted mechanical choke on it. If yours has one, then take the choke off the side and go to a merc. dealer and ask for an electric replacement. You will need to connect a ground wire to one of the choke screws and a ground wire on the engine. You will need a 12 volt source on the engine; a purple wire tap will suffice as long as it is not a resistor wire to the coil. Let us know.

http://www.mercruiserparts.com/Show_Pictures3.asp?dnbr=816596&ivar=images/CRUISE R/816596/13.png&inbr=1014&bnbr=140&bdesc=CARBURETOR+%28ROCHESTER+%2D+4+BARREL%29"
 
"I GIVE UP...SO FAR I'VE C

"I GIVE UP...SO FAR I'VE CHANGED TO NEW GAS...CHANGED THE FUEL FILTER...CHANGED THE IGNITER...NEW IGNITION MODULE...ALSO REPLACED THE CARB AND OPENED THE GAS CAP...

IT'LL RUN FINE WITH THE WATER HOSE HOOKED UP...BUT ONCE I DROP IT INTO THE WATER AND PUT IT IN FORWARD AND LITTLE GAS...IT'LL CHOKE...WONT EVEN GO PAST 1600 RPM...

THE MOTOR STARTS RIGHT UP EVER SINGLE TIME...

IMMA JUS DROP IT OFF AT THE BOAT SHOP TOMORROW...I DONT EVEN KNOW WAT TO CHECK FOR ANYMORE
"
 
"WELL...I JUS GOT A CALL BACK

"WELL...I JUS GOT A CALL BACK FROM THE BOAT SHOP. THEY SEEMED TO THINK THERE MIGHT BE SOMETHING WRONG WITH THE VALVES. BUT TODAY THEY DID A WHOLE LEAK DOWN TEST AND THE COMPRESSION IS GOOD AND THERES NOTHING WRONG WITH THE VALVES. SINCE I'VE REPLACED THE IGNITION MODULE AND THE CARB (USED). THEY'RE JUS GONNA DO A TUNE UP LIKE THE ROTORS N CAPS AND PLUGS N WIRES. SO I TOLD THEM I'D JUS DO THAT MYSELF CAUSE THEY CANT SEEM TO FIGURE OUT WAT ELSE CAN BE WRONG SINCE THE LEAK DOWN TEST CAME OUT GOOD.

ANYONE ELSE HAVE ANY IDEAS THAT MIGHT BE WRONG?
MY MOTOR RUNS FINE WITH THE MUFFS ON NEUTRAL AND IN GEAR. ONCE I DROP IT INTO THE WATER, NEUTRAL IS FINE BUT ONCE I THROW IT IN GEAR. IT WONT GO PAST 1700 RPM. I GUESS MY ONLY THINGS I HAVE TO CHECK NEXT AFTER THE TUNE UP IS THE FUEL PUMP OR WAT??"
 
"Also - I had a similar proble

"Also - I had a similar problem with my MCM 5.7, and it turned out to be a clogged filter screen at the carb inlet (just past the point at which the fuel pump to carb line attaches). It was dying out trying to get on plane. No problem since."
 
"Fuel filters can be a big pro

"Fuel filters can be a big problem. Just replace all to eliminate concern.

Sometimes failing mechanical fuel pumps are more difficult to diagnose. I would put a pressure guage in line and see what pressure you have on the feed line to the carb. Most carbs require require 4 to 7 psi.

Mechanical fuel pumps are not too expensive, so I would replace if any doubt remains.

I keep an electric fuel pump on hand in shop to use in bypassing factory pumps when trying to prove/disprove the fuel pump is an issue."
 
"Sounds as if the carb may nee

"Sounds as if the carb may need a rebuild. If the boat bogs down under a load there may be a problem in the q jet needle valves. DO NOT TRY TO REBUILD THIS CARBORATOR YOU NEED A ROCHESTER CARB TECH TO DO IT! I have a question, when you remove the carb cover, and start the engine do you notice if the choke is opening as the engine warms up? If this is a divorced choke carb you can purchase the choke through any local automotive store. Just ask for a manuel choke for a GM engine. If you are boating in a warm climate ALL THE TIME you may want to temparelley wire the choke open, and see if there is a change in the performance of the engine."
 
"Birdy Yang
When you try to

"Birdy Yang
When you try to accelerate is there any indication of the exhaust being black?? There is a possibility that the power valve in the carb may be seized. They're easy to loosen up by the way. Also try the secondaries and make sure they open freely. In case you're not aware, the secondary upper plates are opened by air, when demanded by the lower throttle plates, being opened mechanically. The upper secondaries also govern the fuel feed to the back two with needle valves in the jets.
Bert

Bert"
 
"I CHANGED THE FUEL FILTER BEF

"I CHANGED THE FUEL FILTER BEFORE TAKING THE BOAT OUT WHEN I FIRST BOUGHT IT AND IT WAS LIKE THAT STILL.

I'M NOT SURE IF THE CARB NEEDS A REBUILD BUT I DID GET A USED ONE AT THE BOAT RECYCLERS CAUSE I ASSUMED MY CARB I HAD FIRST WAS BAD BUT ITS STILL THE SAME.

AND YES I HAVE ELECTRIC CHOKE AND MY CARB AND IT OPENS AS WELL. I'VE EVEN LET THE MOTOR RUN WARM BEFORE I START MESSING WITH THE CARB. IF I CLOSE THE PLATES, IT WOULD KILL THE ENGINE SO YEA...ITS OPENING.

I GUESS I'LL HAVE TO TRY AND SEE WAT THE PRESSURE IS IN THE FUEL LINE THEN."
 
"Birdy
Dont forget you not on

"Birdy
Dont forget you not only have an inline filter but a filter screen on the pickup in the fuel tank and in most cases one on the fuel inlet in the carby.

A couple of years ago one of my 292,s in my Berty was bogging down under load, it would start and idle perfectly and rev crisply but as soon as you put it in gear and loaded the engine up it would die in the bum at about 1500rpm.

I tested everything including the primary and secondary resistance readings of the coil which showed up fine.
Out of desperation I swapped the coil from one engine to the other and the problem changed engines with it.
My best suggestion at this stage is to go back over your fuel system including your carby first and then just stick a coil on it if all else fails.
Cheers
From the Land Down Under"
 
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