28 Special Johnson Wont Stop Snezzing!!!

jstill

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Oct 18, 2008
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12
hello all, i have an 89 28 spl johnson that wont stop sneezing. i have rebuilt the carb, replaced internal fuel lines and adjusted the low idle speed screw. a couple of weeks ago i had cleaned and rebuilt the carb and it ran great for about 8 hours of running time. it turns out the insullation inside the engine cover was getting in the carb and ultimately clogging the jets. i took all the insulation out and cleaned the carb again and replaced the fuel lines( it looked like they were detiriorating). the engine is still sneezing but if i sit there and keep pumping the ball it runs fine. this tells me that either the ball is losing its prime somehow and there is a lack of fuel getting to the carb or maybe a faulty fuel pump. i dont know. is there any test i can do to troubleshoot this problem. any and all help would be very much appreciated.:mad::confused::(:eek:
 

tashasdaddy

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Re: 28 Special Johnson Wont Stop Snezzing!!!

did you run some stranded wire thur the jets. also on the motor side of the carb throat, there are 3 small hole in the top of the throat, these have to be clear, you remove the top core plug to clean them. i have sometimes been successful, using a small paper clip, formed into a L, and cleared the holes from the throat side.
 

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freddyray21

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Re: 28 Special Johnson Wont Stop Snezzing!!!

if the line is bad it can be the cause of the problem. change the line and see. Pretty cheap to do.
 

Bear 45/70

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Re: 28 Special Johnson Wont Stop Snezzing!!!

Rather than spend the money on a new fuel line, just keep squeezing the bulb as the engine idles, if the problem goes away, then either the fuel line or tank have an air leak in the fuel line. If not the the carb is too lean. Either raise the float level or buy a size or two idle jet.
 

tashasdaddy

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Re: 28 Special Johnson Wont Stop Snezzing!!!

i assume the motor ran good before you started having insulation problems. the lean sneeze is lack of fuel, you are getting fuel to the carb for it to run. if the hose is hard or stiff, bulb not plyable, the replace. be sure to get a J/E fuel line. there are several look alikes, suzuki looks identical, but isn't. the bad line would show up more at higher speeds.

the only way the motor gets fuel at idle, is thur the jets and then thru the holes in the top of the throat. you may have to rotate the throttle plate to see the holes.
 

Harker

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Sep 21, 2003
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452
Re: 28 Special Johnson Wont Stop Snezzing!!!

How would the insulation from under the hood get into the jets? If it was sucking the insulation into the carb, wouldn't it plug the reeds? I would pop the carb off and look in the intake and see if it is packed in the reeds and air cleaner if it has one.
 

freddyray21

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Re: 28 Special Johnson Wont Stop Snezzing!!!

Rather than spend the money on a new fuel line, just keep squeezing the bulb as the engine idles, if the problem goes away, then either the fuel line or tank have an air leak in the fuel line. If not the the carb is too lean. Either raise the float level or buy a size or two idle jet.

Uh read his first post he has already done that.

My opinion is if continuing pump the bulb makes it run fine then that is where I would start. I had the same problem on a 63 40hp and stubbornly would not change the bulb line. Once I gave up and did it ran fine.
 

Bear 45/70

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Re: 28 Special Johnson Wont Stop Snezzing!!!

I missed the bulb part. Yes, replace the hose, not just the bulb and don't get just the hose, replace the connectors too. But it could still be a bad pump.
 

freddyray21

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Re: 28 Special Johnson Wont Stop Snezzing!!!

you are right it can still be a bad pump, but a line is where I would start. if its been while since it has been replace then it needs it anyway. I am luck as I have several lines I can swap out and see if that is my problem.
 

Bear 45/70

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Re: 28 Special Johnson Wont Stop Snezzing!!!

Years ago a local marina went out of business and I bought the fuel line connectors, primer bulbs and fuel line and clamps. I only use 3/8" line anymore for all my engines.
 

tashasdaddy

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Re: 28 Special Johnson Wont Stop Snezzing!!!

(Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)

Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.

Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

Note: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor. It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing this final adjustment due to the fact that one of the valves might be initially set ever so slightly lean.

When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.
 

freddyray21

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Re: 28 Special Johnson Wont Stop Snezzing!!!

still don't think it's carb adjustment if pumping the bulb will make it run fine.
 

Bear 45/70

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Nov 2, 2008
Messages
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Re: 28 Special Johnson Wont Stop Snezzing!!!

still don't think it's carb adjustment if pumping the bulb will make it run fine.

I agree with freddyray. Leave the carb alone until you solve the fuel feed problem. Then if it still has issues, then dink with the carb.
 

tashasdaddy

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Re: 28 Special Johnson Wont Stop Snezzing!!!

jstill, you have a private message.
 

jstill

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Oct 18, 2008
Messages
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Re: 28 Special Johnson Wont Stop Snezzing!!!

I agree with freddyray. Leave the carb alone until you solve the fuel feed problem. Then if it still has issues, then dink with the carb.

i have replaced external fuel line and primer ball. still sneezing. maybe fuel pump? im stumped.
 

jstill

Cadet
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Oct 18, 2008
Messages
12
Re: 28 Special Johnson Wont Stop Snezzing!!!

i have replaced the whole fuel system(lines, tank). and rebuilt the fuel pump. cleaned the carb and adjusted it. is there anything else i can possibly do. oh and i dont see any fuel leaking anywhere at all. thanks for any help.
 

huckelberry

Seaman
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Sep 1, 2008
Messages
56
Re: 28 Special Johnson Wont Stop Snezzing!!!

I had the same problem with my 25 evinrude. I got rid of the walmart tank connector and hose and bought a brp hose assy. I also teflon taped the tank connector before installation. Now it idles like it should, no sneezing and cutting out.
 
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