70 hp Johnson carb float needles sticking

bowhunter71

Seaman Apprentice
Joined
Apr 17, 2006
Messages
39
I have a 78 Johnson 70 HP.I just got it about a month ago.The first trip to the lake was trouble free the motor ran great.The second trip was not as good.The motor started fine backed it off the trailer and motored over to the boat dock and it stalled out and would not start.It acted like a fuel problem so I checked the primer bulb it was still hard so I checked the fuel lines and found that there was a small leak in one of the lines going to one of the carbs.So I replaced all the fuel lines on the engine and it still would not start.I gave it a little shot of starting fluid and it fired right up.I figured that carbs were probably gummed up so I took it home and took the drain plugs off the carb bowls but nothing came out.I then pulled the carbs.All three of them were spotless inside and the floats were fine but the float needles were stuck on all three carbs.I pulled them out and they looked fine I then put them back in and put everything back together. I Hooked the fuel line up gave it a couple pumps and walla she fired right up.I let it run for a few minutes and no problems.I Took it to another lake and everything went fine.So I figured that me or my father when we hooked the fuel line up the other day that one of us pumped it up to much and the floats pushed the needles tight into their seats.But tonight I went back to the lake where I had the troubles and It did it again same thing the float needles were stuck.I took the carbs apart again and pulled the needles loose and put it back together.It fired right up and ran fine all evening. The only thing I can come up with is that maybe it is the travel to that lake that causes it to happen because it is a real bumpy ride to this lake.Could it be the 2 cycle oil I am running or the mixture.Or maybe the needle tips are bad and I can not tell by just looking at them.If anyone has any ideas let me know<br />Thanks,Jeff
 

jim_in_day

Petty Officer 2nd Class
Joined
Aug 29, 2005
Messages
175
Re: 70 hp Johnson carb float needles sticking

Hi Jeff, Welcome to the forum. An expert will be along soon, but until then, I have a 76 RUDE 70hp, and I am very familiar with the insides of the carbs (I rebuilt them 4 or 5 times getting everything just right..... learning curve) The needles may have a very slight ring of wear in them, and the seats may also be slightly worn. I would get an OEM Kit and rebuild them, you have had them appart several times now, so it should be an easy job. Just make sure to get the float level correct, The 3 bangers are very prone to run lean (or rich) if the floats aren't exactly correct. The oem service manual is also a must have for that motor. Good luck and somebody with real experience like DHADLEY, Joe Reeves, Walker or one of the other true experts will be along soon.
 

KYHunter2

Chief Petty Officer
Joined
Mar 20, 2006
Messages
512
Re: 70 hp Johnson carb float needles sticking

I'm not one of the experts, but I've rebuilt several carbs.<br /> "one of us pumped it up to much and the floats pushed the needles tight into their seats"<br /> This has nothing to do with the needles , seats, floats, or anything else, with the carbs. <br /> Other than supplying fuel, to fuel pump.<br /> As jim said buy oem kits, and rebuild them . Alot of kits have instructions in them<br /> Be sure to clean / soak them in carb cleaner , not just, spray them out.<br /> Blow out with compressed air.<br /> You've allready had them apart , could have saved a bunch of time and work , just rebuilding them .<br /> The kits are cheap , I'd get floats too, but thats just me . You may not need them .<br /> The needles probably stuck, from the carbs being dirty.<br /> The little springs, were on the needles/floats, correctly right?<br /> A bumpy ride , wont do anything to the carbs , etc. <br /> NO MORE STARTING FLUID !!!!! use premix in a spray bottle. <br /> You will do serious damage, to your engine, using ANYTHING ELSE.<br /> If you intend to work on your own motor , great .<br /> Get a manual (oem). <br /> If you have no history on your motor. <br /> Rebuild water pump , do a compression test, spark test , fuel system check , replace or add water seperator/ fuel filter, rebuild carbs , do a link and sync. etc.<br /> I've bought several used engines. <br /> I have learned , often the hard way .<br /> To go over the motor completely , and if I have a doubt ,do what I posted above. <br /> Its really simple, make sure you have good clean fuel , and a operating fuel delivery system .<br /> Good spark , and motor is cooling . <br /> It will save alot of headaches and money , in the long run.<br /> Please dont forget to forget the starting fluid.<br /> <br /> Good-Luck, :) <br /> KYHunter
 
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