200 Johnson resurrection

[jay's snake]

1996 200 JOHNSON VENOM
Model J200STLEDM
Serial G 03972270

I repaired this engine (with lots of help from Championman and others) after it burned a large hole in the #1 piston about 6 years ago. Since that time, I have only run the engine a handful of times (I can't believe 6 years has gone by so fast). Anyway. I recently pulled it out of the garage (it has been stored in the garage the entire time) and it started fairly easily. I did take all the carbs apart to clean the jets that were restricted with gummy fuel.

I took it out on the water and it starts good idles fairly well, but bogs as you give it gas. When it finally takes off, it sounds pretty good at higher speeds.

I pulled the plugs and found #1 looks much different that the others and since that's the cylinder that failed previously and I never really figured out why it is a concern. It looks dry in comparison to the others that are oily. I will post some photos soon. Thanks!!

[316jughead]

If your concerned about that cylinder getting fuel, take a spray bottle, with gas and oil mix, with motor running spray a fine mist shot in that cylinders carb. If it's running lean the motor should pick up rpm. Don't use anything other than gas and oil mix. On this motor make sure you have the correct carb.

[jay's snake]

Here are some photos of the plugs. I'm primarily concerned with #1. All the plugs with the exception of #1 are a little oily which I think is normal for a two cycle engine. I'm concerned with #1 because it looks so dry and that cylinder was the one that leaned out previously.

[316jughead]

I agree with you, #1 is way lean, the other two cylinders on that side are oily, that may be a spark problem on those two, 2 & 4 are maybe somewhat lean, but when I changed jets on my own motors that was what I wanted, but no leaner, 6 looks funky, dirty but not oily. Was there any idle time before pulling the plugs? I think you should do more on the carbs than just clean the jets.

[jay's snake]

I'm thinking the ideal plug condition should be a little oily and the insulator should be tan in color?
I did have to idle for about ten minutes on the way back to the ramp, but that does not explain why some plugs are black and others are not.
I think I will do a more thorough cleaning on the carbs and see if that helps. By the way, the main jets are all 65 except for #2 which is 67. The intermediate jets are 20 for 1,2 and 3 and 23 for 4,5 and 6. I have no idea why the different sizes, but I think I read that it was advised to put a larger jet in #2 to solve a lean problem in that cylinder.

[omcforever]

I read my plugs on a test wheel or after a run at speed with load and while running say 4500-5500 rpm and trimmed down to keep speed down and just turn key off(if you have no test wheel).....will get back wash but you will get a true read of plugs as well...have to troll back to ramp but idling can give false reads on plugs(especially if VRO is bypassed and you pre-mix). I would def do what Jerry says. Clean them there carbs with all new parts and gaskets/verify proper orifices, fuel delivery, pressure, ect. Fix fuel delivery before running again. Lean is a quick killer. I would also verify linkage, carbs opening right and link and sync and timing.

[316jughead]

[QUOTE=jay's snake;9716643]I'm thinking the ideal plug condition should be a little oily and the insulator should be tan in color? Yes

I did have to idle for about ten minutes on the way back to the ramp, but that does not explain why some plugs are black and others are not. If you say so!

[jay's snake]

Yeah, you're right idling does make a difference and I'll try to read them next time without idling back to the ramp. Thanks!