1997 20hp Johnson Problems J20CREUM

[SS Freak]

1997 20hp Johnson Problems J20CREUM

 

[AlTn]

Re: 1996 20hp Johnson Problems

Re: 1996 20hp Johnson Problems

compression, spark, fuel...compression test, spark test <jumps an open air gap of 7/16" >, fuel < fresh mix free of water >...post these findings with your model no. and describe <or a pic > of the plugs when removed

 

[SS Freak]

Re: 1996 20hp Johnson Problems

Re: 1996 20hp Johnson Problems

I will report back on this.

 

[losnbama]

Re: 1996 20hp Johnson Problems

Re: 1996 20hp Johnson Problems

sounds like youre losing fuel pressure. after the ignition testing, check for leaks everywhere there is a hose or gasket even the fuel tank .my fd19 did the same thing. then after inspection the fuel pump inlet cover was cracked. losing fuel pressure. and a good carb cleaning wouldnt hurt since its been 3yrs since the last one.

 

[SS Freak]

Re: 1996 20hp Johnson Problems

Re: 1996 20hp Johnson Problems

1997 20hp Johnson Problems J20CREUM

 

[SS Freak]

Re: 1996 20hp Johnson Problems

Re: 1996 20hp Johnson Problems

1997 20hp Johnson Problems J20CREUM

 

[losnbama]

Re: 1996 20hp Johnson Problems

Re: 1996 20hp Johnson Problems

to me that plug looks good. and yeah its a fuel problem. if you dont want to clean the carb(but should!) run Clean gas(no oil) through the motor. FOR NO MORE THAN 10sec!!! this will clean the seats and idle holes in the carb.then drain the carb bowl,and with the plugs out and choke pulled,flush the fuel system with mix by pulling the stater rope 10-15 times. basically flooding it. wait 10 min to let the gas evaporate this will also put a good shot of oil on the internals set the low speed needle (from gently seated) to 1 1/2 turns out then give it a couple pulls. then read "adjusting carbed motors" in the secret files post. btw wats the model #?

 

[scanman]

Re: 1996 20hp Johnson Problems

Re: 1996 20hp Johnson Problems

That plug looks a lil darker than normal to me. IMHO, I'd buy a new one, or clean that one up real good. That color indicates, usually, that the motor is either runnin rich or not burnin all the fuel it's bein fed. I'd definately clean the carb, it'll be worth your time. If ya don't wanna do that, replace the plug & run it again, for about 10 min. If ya get the same color on a new plug, it's a carb issue. Your "shaking can result from a "lean" or "rich" carb, or from a plug with a cracked resistor, so that is really a symptom of multiple problems. Just from your pic, I'm guessin there's too much oil in the gas, or the mix screw is too far open. could be a lot of things, but start with a new plug & see what you get. BTW: be VERY CAREFULL runnin it on straight gas!!!!

 

[SS Freak]

Re: 1996 20hp Johnson Problems

Re: 1996 20hp Johnson Problems

1997 20hp Johnson Problems J20CREUM

 

[SS Freak]

Re: 1996 20hp Johnson Problems

Re: 1996 20hp Johnson Problems

1997 20hp Johnson Problems J20CREUM

 

[SS Freak]

Re: 1996 20hp Johnson Problems

Re: 1996 20hp Johnson Problems

1997 20hp Johnson Problems J20CREUM

 

[SS Freak]

Re: 1996 20hp Johnson Problems

Re: 1996 20hp Johnson Problems

Any ideas as to how to adjust the high speed jet on this carb. There is a tube there hooked to pt#3. Nothing showing but the tubing and the joint.

 

[SS Freak]

Re: 1996 20hp Johnson Problems

Re: 1996 20hp Johnson Problems

1997 20hp Johnson Problems J20CREUM

 

[jasper60103]

Re: 1996 20hp Johnson Problems

Re: 1996 20hp Johnson Problems

That year (1996) corresponds to the CE certification. You have a 1997 motor.

 

[AlTn]

Re: 1996 20hp Johnson Problems

Re: 1996 20hp Johnson Problems

compression test results?...as you stated there's only an adjustment for the low speed idle/mix via #15. The main jet is #24 < high speed orfice > which enters the side of the well <#3 >. This jet must be spotless. The small hose <#4> supplies fuel for the idle circuit. I'd advise you to be extra careful when disassembling these parts as that little plastic well is pricey. Regular carb cleaner and that plastic top don't mix well together, so use something else that is plastic friendly when cleaning it. The remainder of the carb body and internal circuits can be cleaned with spray carb cleaner or soaking in carb cleaner. My only experience with this type of carb was on a 1992 9.9. It was hard to start cold, no idle, and wot seemed fine. After my first clean and kit it started well, idle was so-so, and there was a bog on going to wot. Carb off float readjusted to put the free end higher than level at the front. Starts well, idles better, still a bog on transition to wot. Carb back off, float adjusted even higher at free end. Starts easily, idle is rich, no bog at transition. Sooooo.. after 3 or 4 off an on's with float adjustments always increasing the amount of fuel in the bowl, it does as well as it's owner wants it to, but the idle mix is still too rich in my view. Your experience will hopefully be better.
The water pump and impeller can be found under the gearcase parts diagrams.

 

[SS Freak]

Re: 1997 20hp Johnson Problems J20CREUM

1997 20hp Johnson Problems J20CREUM