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Carb losing prime

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boskey_iv

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650cfm rochester qj loses it&#

650cfm rochester qj loses it's prime after about 5 hrs. ether helps but is not the solution.mounted on an '88 proline 23'walkaround with a 5.7 (350) omc cobra.any suggestions?
 
"Ayuh,... Your carb is leakin

"Ayuh,... Your carb is leaking Internally...
Rebuild it paying particular attention to the welch plugs in the bottom of the bowls..."
 
"or just epoxy over the bowl p

"or just epoxy over the bowl plugs in place. fuel tank repair epoxy/JB weld etc... no need to clean it, if the plugs have been leaking, it's very clean."
 
"A 650 CFM Q-jet????

Maybe

"A 650 CFM Q-jet????

Maybe the sealing plugs; unlikely on a 170 casting.

Have you measured the fuel level in the float bowl? Is it low or empty?

As suggested earlier, verify the ignition system is A-O-K before messing with the carb."
 
"Thanks to all who responded.

"Thanks to all who responded. I was told that the main metering well plugs could very well be the culprits and that the epoxy fix would work. This seems to be the direction I'll be heading 1st.This boat is a recent purchase(mid August)and previous owner said the problem just started in spring launch.Markings on left side of carb are 17059286 with the numbers 2157 directly below.RE;Makomark the bowl level checked out to be of sufficient levels.Thank you.RE;Chiefalen & just-in-time,spark,timing,coil,plugs and wires are doing a great job delivering proper fire and vapor lock doesn't seem to be an issue.Thank you both. I didn't mention before that after the initial warm up, the motor fired like it should. On the first revolution. One bump of the key and we were off and running. It's just that after 5 hours of anchor or more of down time it would take a long time to fire and would flood very easy as well as drain battery. A shot of ether improved starting immensely but was not a cure.Might even change out fuel pump just to be sure. Thanks again to all and I'll let you know next spring how things went. Sincerely,Boskey IV"
 
"If the fuel level in the bowl

"If the fuel level in the bowl is sufficient and you flood very easily...sounds more like ignition than fuel....going on the guess that the fuel is fresh.

I was referring to the the fuel level, in the carb, when the 'hard to start' occurs. If it is where it was when measured in the 'cold' state, then nothing has leaked out...

If you find the well plugs leaking, you'd be better off with the drill, tap, and epoxy in the plug approach than just dabbing adhesive over the existing plugs."
 
before changing the fuel pump

before changing the fuel pump test the psi it is giving you 4-7 no less. Make sure there is no air entering the system say at a clamp and the hoses are good.
 
"Hey Chief, been a while...

"Hey Chief, been a while...

To the OP, I'm no expert by any means, but I had the same problem when I first got mine running. After JBWelding the plugs, the problem was better, but not solved. I doscovered that the brand new float (as well as the old one that ended up being good) was not holding the 5-6psi the pump was putting out. Thus, it would flood very easy and would dribble slightly when turned off. After getting tired of everyone telling my newly rebuilt carb, needed to be rebuilt, I bought a regulator at checker. I set it for 3psi and problem solved.
I used my compressor and put 5 psi to the carb inlet. It never would stop unless I had the float set almost all the way down.
If you test this way, make sure your bowl is full, and there is fuel in the line so your pushing fuel to the carb as it would normally be operating."
 
"Remy High five,been a while,

"Remy High five,been a while, hope all is well with you and yours.

Op you have gas in the oil pull the stick and smell the oil. Before you start it.

No smelly oil, no easy start, then i have known guys to put a primer on the line. Could use a squeeze bulb.

See once the bowl is full it has to be leaking somewhere. Thats not the same as losing prime.

You do pump the throttle 2-3 times when cold. And put the throttle 1'3 way down in neutral and try to start it."
 
"Thanks Chief, all is well.. M

"Thanks Chief, all is well.. Merry Christmas to you.

I have pondered putting a primer on mine as it seems that after sitting for a week the bowl is still empty. I'm not sure if it's still a leak somewhere or if it's evaporating out the vent. Seems like a week is much time to evap the entire bowl."
 
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