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Carb Rebuilt Engine Wonbt Start

btmline

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1987 Merc. 340 h.p. Thunderbol

1987 Merc. 340 h.p. Thunderbolt Ign. Had Q-Jet rebuilt at shop. Put on engine. Wouldn't start so gave it a shot of ether. Started up and ran for about 30 min. Shut off and restarted several times. Next day would not start even after shots of ether although the ether fired off indicating I was getting spark. Without a shot of ether it would not fire at all. Any thoughts? Thanks.
 
"Ayuh,.. Is the carb getting f

"Ayuh,.. Is the carb getting fuel,..??
If not,.. Check the Fuel Pump,+ the rest of the fuel system...
If it Is,... Get another Carb...That 1's got problems.."
 
all i can add is how much fuel

all i can add is how much fuel is in the tank?

any water in the fuel? how old is the fuel?
 
"Ayuh,... Swap the Carbs,&#43

"Ayuh,... Swap the Carbs,+ see if the problem follows it..."
 
"The fuel may be OK, but you h

"The fuel may be OK, but you have a fuel pump and,hopefully, a fuel filter on each engine.
It's either a fuel delivery problem (pump or clogged filter) or a carb problem. Swap carbs from the other engine - if no go then it's the pump or filter. Does each engine have a separate supply line from the tank? If so it could also be the anti-siphon valve for that engine is faulty or has picked up some trash from the tank."
 
I didn't have any extra ga

I didn't have any extra gaskets when I was at the boat so couldn't swap carbs. Separate supply lines for each engine. I appreciate I could have picked something up but it ran the first time after a shot of ether and I did stop and restart several times. Just wouldn't statr the next day. Will check fuel delivery further when I can get back to the boat.
 
"Do you get 2 squirts of fuel

"Do you get 2 squirts of fuel in the carb when the throttle is pumped. Remove linkage and open throttle quickly, the accel pump should squirt 2 streams consistantly thru most of the stroke. If not, is the linkage connected to the pump lever?
Or there is not enough fuel in the bowl to fill the accel pump cavity.
Or yer just out of fuel (in the carb).
Don't do anything to that rebuilt carb to Void the warrentee.(like open it up)."
 
Thanks for the tips. I'll

Thanks for the tips. I'll check further when I can get back to the boat. May not be for another two weekends but I'll report back.
 
Got back to the boat this week

Got back to the boat this weekend. The crab is totally starved for fuel. Fires off using ether or gas poured in but then will not start. No fuel smell and can not see any fuel squirting from the nozzles. Disconnected fuel line at inlet and got steady stream when turning over. Put new fuel pump on and changed both filters anyhow and nothing. Took carb off and attached small line and tried blowing into it and can't get any air to pass through. Something is blocking passagees.
 
1987 model? What engine and w

1987 model? What engine and what carb?

How about "rock hard" varnish throughout the carb. Buy a reman. or send yours out to a company that remans. carbs w/a garauntee.
 
Most likely the float is jamme

Most likely the float is jammed shut or got hung upon something inside the carb keeping it closed
 
Good point Bt Dr; never though

Good point Bt Dr; never thought the needle valve would stay completely shut since the metal tang on the float is so pliable. Learn something every day.
 
"Every carb I do , i turn it u

"Every carb I do , i turn it upside down and try to pass some air thru it, then right side up to see if i can`t. could also do the "shake test" and listen for the "tinkel,tinkel" of the float."
 
"BT:
great idea but i think t


"BT:
great idea but i think the reference is off. If its upside down, the float should be up and the needle closed = no air. If right side up, float should be down (if bowl is empty) and air should flow thru the inlet.

You should be able to see if thte float is stuck with a thin rod (coffee stirrer), going down thru the vent hole just in front of the flame arrester stud. if the float is up, the rod will stop when ~ 2" of it are in the vent. If it goes in over 2.5", the float is down and something is in the inlet system is wrong. either way sounds like its time to find another shop.

with nothing coming out of thte accelerator ports, I'd say no fuel in the bowl. you may find some excess teflon tape in the inlet passages or the needle and float weren't reassembled correctly. "
 
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