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1974 70hp johnson outboard

1

17arrowglassstinger

Contributing Member
hello i have an issue with my

hello i have an issue with my motor and im trying to narrow it down to either starving for fuel or air how do i go about narrowing it down my primer bulb and fuel lines are ok thanks for any help
 
"I do not see how it can be st

"I do not see how it can be starving off air, but if it runs OK with the cover off but not with it on its because exhaust gases are leaking under the cover.
So if its fuel.
A defective fuel pump can be diagnosed by pumping the primer bulb.
A dirty carb might be diagnosed by playing the choke.
A non seating needle valve will be diagnosed by disconnecting the fuel line
Sure the pick of from the tank is not restricted? (not sucking the ball down?)and the tank venting properly (tried taking the cap off?)"
 
I'd need to know exactly w

I'd need to know exactly what that engine is doing or not doing.

Have you checked the compression and spark?
 
yes spark is good and compress

yes spark is good and compression is good my motor will go up to 3000 rpms then i will throttle more and it will start bogging down but if i go tp 3 grand and stay there after like a minute it will go higher and it will stay there its just when your trying to get on plane it will do it it idles great and i rebuilt my carbs and it does the same thing either if the cover is off or on and pumping the primer bulb dont do anything when the problem happens
 
and when i press the choke tha

and when i press the choke that doesnt do anything except make the motor die like it should do how do i check for a non seating valve what exactly do i do and i will try taking the cap off the gas tank but the vent is open
 
"FIRST THING I'D DO,W/THE

"FIRST THING I'D DO,W/THE INFO,U PROVIDE,is clean the carbs,and inst new carb kits,..at the least,..if done properly,is u have covered a carb problem......i suspect a float/needle is not dropping,or,hs jets are dirty..."
 
k i cleaned my carbs and rebui

k i cleaned my carbs and rebuilt them what would make a float not drop because when i have the carbs apart they all drop and i took a wire and manualy cleaned jets what does the float do?????
 
"the float,regulates,the amoun

"the float,regulates,the amount of fuel,admitted into carb bowl....like a toilet float....to high,it floods,to low,starves for fuel...u did a good thing,even,if that does not solve,ur imediate prob....prob,80% of eng probs,are carbs..."
 
ok thanks for the info would t

ok thanks for the info would the floats not being adjusted the way they should cause this problem cause i cleaned those carbs like 3 times then i rebuilt them but im new at working on outboards and i thought i adjusted them the right way but if they are not at 3/4in would that make it bog down cause it not letting enough fuel for the motor to run and is there a way i can check this when its doing it thanks for all the help
 
"Matt,
It’s possible that the

"Matt,
It’s possible that the idle circuit is too lean, on one or more carburetors, resulting in insufficient fuel during the transition to the high speed circuit. This often results in bogging at the transfer point were the idle circuit delivers fuel to help transition to the high speed circuit. Have you checked the idle orifices and the idle restrictor orifices for obstruction? It would also be wise to remove the core plugs at the idle and transfer ports checking that they are clean. Just something to think about."
 
thanks for the info i went out

thanks for the info i went out today to try it and i guess it fixed itself because theres not a problem now it will go now without a problem but now my wires for my gauges shorted out so now i got to worry about something else but thanks for the info
 
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