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Rochester quadrajet problem flooding

D

duduk

New member
"Hi all
first: Thank you all

"Hi all
first: Thank you all for this FINE web site & the forum, it has helped me many times

Now: my problem

i have a 1986 Mercruiser 470 4cy. 224 series 190 HP..
have been having problem w/ my 4-bbl Rochester quadrajet carb.
it has all started 4~5 moths a go, my carb has start flooding, so we had the carbes rebuild,
same problem,
took the carbs back to the shop, he did some fine tuning, but the problem did not go away, we took the carb back to him 4 times, same problem...
he has adjust the float, still the same...

so i found a reputable carb places in CA and ordered a re manufactured carb , same problem....


now that i think i remember that we have replaced the fuel pump also at the same time, i just ca't remember if it was before or after the carb reaper. our boat mechanic told me that we have 6lbs pressure, was told that i should have 3.4lbs,..
the shop who sold me the pump is telling me that the pump is fine, and my carb pressure should be 3 to 7 Lbs...

no w i'm lost
i don't know what to do


can someone please help me
Moses"
 
"If the fuel pump is leaking i

"If the fuel pump is leaking internally, excess fuel will be sucked into the carb thru the clear hose; is it delivering fuel thru it?"
 
HI: Thanks
the clear hose of

HI: Thanks
the clear hose of the pump is just hanging dawn
and no it has no fuel in it
 
It is supposed to be connected

It is supposed to be connected to a nipple on the fuel pump or you'll blow up the boat when the fuel pump diaphragm leaks. If there is no nipple on the pump then you have an auto and not marine fuel pump--change it!
 
"it's connected to the p

"it's connected to the pump not to the carb, i was told i need to let it hang dawn, this way if the pump is leaks i can see it

i so a fuel leaking from it so we have replaced the pump, on my carb i don't see a nipple to connect the clear hose

are you sure it should be connected to the carb and to the pump ??"
 
"My 1994 5.7 V-8 ran rich. I r

"My 1994 5.7 V-8 ran rich. I replaced the motor (for several reasons) and bolted the old carb on without rebuild or anything. Old carb on new engine runs like a top. I believe the old engine was just worn out and could not burn the same amount of fuel it once did. You've changed the carb 4 or 5 times, time to look elsewhere. A compression check and leakdown test might be a good place to start."
 
"moses, if you dont follow guy

"moses, if you dont follow guy`s advice on that hanging hose getting hooked to the carb ,you`ll be speaking to Moses personally,or if you`ve been bad boy , that other moses down below"
 
"The carb has to have a nipple

"The carb has to have a nipple at the top rear of the venturi or the carb base rear. The jackass that told you to hang the leak detection hose down should be barred from boating!!!
crazy.gif


Now that statement is one of the dumbest I have ever heard. Did he tell you to put a bucket under the hose to catch the leaking fuel and strike a match to check it? My apologies!

Take it to a dealer and ask them to install a nipple for the hose. Safe boating to all."
 
"no need for a match [img][/

"no need for a match
i do smoke



Thank you !!!!

ok found a nipple that had a plug on it, now the the hose is connected...

whats next .. i still have the same problem w/ the carb..
"
 
"Bt Doctur [img][/img] looks

"Bt Doctur
looks like i need to see Moses soon, he just might have answer for me ;) on my carb.. problem"
 
"Will the engine run?
Does

"Will the engine run?
Does it idle? What RPM?
Is the timin g set right? What degree?
How do you know it is flooding? Explain it.
When does it flood? Explain what happens.
Will it restart right away?
What do the spark plugs look like? Black, brown or tan?
What other work have you done?"
 
"Good morning
Thank you For

"Good morning
Thank you For your help

The engine is new rebuilt, less then 2 hours on it. it was rebuilt do to bad oil pan......

Timing is set & spark plugs are new, no Black, brown or tan, it's as new

runs fine when initially started, 20~30 seconds after you see gas gushing out from the "flute" on the top of the carb.

i just got a new pressure tester that can measure more then 7psi, will test the pump one more time my self"
 
"I had the same problem with m

"I had the same problem with my 1988 3.7...installed a new fuel pump...carb flooded! Only reason I replaced the fuel pump was because it was 20 years old! Re installed old fuel pump...back to normal. Still scratching my head! Read somewhere that if you pull the pump apart there should be a certain number of holes in the diaphram for a particular year of engine, but I can't find it any more. Any help would be appreciated!!!"
 
the MARINE carb does not have

the MARINE carb does not have that nipple at the base. it not used . was most likely used for the pvc system or the vac. supply for the brake booster. the nipple we refer to is at the top of the carb body. it allows the fuel from a ruptured diaphram to dump directly into the carb and not the bilge.
 
It is safer than hanging down.

It is safer than hanging down. Do you see a threaded hole at the top rear of the carb where hole passes thru to a boxed area? That is where the "L" shaped nipple threads in the carb.
 
Are the carburetor floats bras

Are the carburetor floats brass or composition? Check for leaks if brass and gasoline absorbsion if composition. Are fuel filters and water separators in place???
 
"HI

the test on my pump:

"HI

the test on my pump: 9 lbs
so i took took out the other pump from our other engine and installed on port side engine that i have been having soooo much problems.. it worked just fine no problems.... but looks like i need one more pump since this one also has started to dump fuel

the old pump is made by Carter, any idea who might have them ??



Thanks Guy Gaspar

i'll have our carb shop replace the carb w/ one that has a vent hole

Thank you for your help"
 
"fuel pump part #861676A1

R

"fuel pump part #861676A1

Rochester carb #1347-9142A2

The parts are available from this site. If you can't find them, NAPA stores will carry the fuel pump and maybe the carb. You may need to order item #4, part #22-54090.

Go to this site and look at item #4 on the fuel pump picture.

http://www.mercruiserparts.com/Show_Pictures3.asp?dnbr=%2012488&ivar=images/CRUI SER/12488/13.png&inbr=908&bnbr=60&bdesc=CARBURETOR+AND+FUEL+PUMP+%28180%2D190%2D 3%2E7L%2FLX%29

That is what the plastic vent attaches to on the carb."
 
"MOses
By connecting the clea

"MOses
By connecting the clear hose from the fuel pump to the vacuum inlet at the base of the carb, you are essentially opening up a vacuum leak into the induction system. A quick check on the net indicates Rochesters work between 3-5 lbs pressure. anymore and needle may be blown off the seat causing your flooding.
Bert"
 
"HI


the new fuel pump

"HI


the new fuel pump did it !!! it's ok
but now i have the same problem on my other carb


this is a never ending story
i'm back to step #1 yet one more time"
 
"Hi
Thank you All
All of my

"Hi
Thank you All
All of my problems have been solved, except one
the clear hose from the fuel pump, have no connection / nipple on the carb, can someone please post a picture to show place of the connection ?? i just don't have any place on the carb to connect


Moses"
 
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