40hp Dead Top Cylinder

[mebehoof]

Is Fuel getting into the Carb Bowl?
Is the Fuel getting through the Circuits within the Carb?
Correct Gaskets used inside the Carb, which have all Fuel and Air Circuit Passages open?

Keep in Mind, we can not see, hear, or touch your motor. We can only go by what info you are telling us. Sometimes Videos help, but don't often provide good Audio, so they are of limited Value

jimmbo,
Yes on fuel in float bowl.
No way to tell if fuel is passing through internal carb passages.
Yes on correct gaskets, needle/seat, plugs, nozzle gskt, intake gskt, o-rings correct and all the gskts were cut for the passages that exist on this carb.
Air circuit passages are open. I have some very tiny, tiny tip and brush cleaners for this type of work. (in my other life I was a dealership mechanic then owned my own place until retiring so I couldn't even give you an estimate on how many carbs, injectors, throttle bodies, etc. I've dealt with)

Still the nagging issue is that the dead cylinder follows the top carb. I cleared all the passages multiple times to be sure, checked and rechecked but here I am.

Thanks for reading,
mebehoof

 

[saltchuckmatt]

You say the same things over and over and over and over.....I feel sleepy.

Reeds don't follow carbs....I can't even remember what your problem is.

All's I know is you have gas on your hands and you were advised to....what?

Best to go see Mr Evinrude service man.

 

[Crosbyman]

do you or don't you feel a good suction on the carb face like on the bottom carb when the engine is turning.

if you don't it will never suck fuel out of the carb....simple. no gas no explosions

 

[jimmbo]

It will have higher Vacuum downstream of the Throttle Plate, at Idle, and Low Speed, and isn't drawing from the Main Nozzle.
It appears that this Carb is not supplying Fuel to the Idle/Off-Idle Circuit. Of course not actually seeing the Parts does hobble Diagnosing.
Looking at the Parts Diagram, the Idle Circuit isn't fed via a tube passing through the Main Nozzle but through a Passage in the Fuel Bowl and Carb Body

However, that said, the OP says the Engine didn't respond when Fuel was Sprayed into the Carb of the non-firing Cylinder... Maybe it is actually flooding the engine, not starving it

 

[saltchuckmatt]

Spark plugs and even the air would prove that!

 

[jimmbo]

Well, there are more than s few things that just don't line up or make sense regarding this engine...

 

[mebehoof]

It will have higher Vacuum downstream of the Throttle Plate, at Idle, and Low Speed, and isn't drawing from the Main Nozzle.
It appears that this Carb is not supplying Fuel to the Idle/Off-Idle Circuit. Of course not actually seeing the Parts does hobble Diagnosing.
Looking at the Parts Diagram, the Idle Circuit isn't fed via a tube passing through the Main Nozzle but through a Passage in the Fuel Bowl and Carb Body

However, that said, the OP says the Engine didn't respond when Fuel was Sprayed into the Carb of the non-firing Cylinder... Maybe it is actually flooding the engine, not starving it

Problem Solved !!!

A big Thanks to jimmbo, racerone and everyone except that one guy LOL you know who you are LOL.

The answer was in jimmbo's last reply and racerone's answer to that.

Here goes, as you all know when I first unwrapped and started the engine this Spring the Choke Primer was leaking so I bought one on Amazon (bad idea) and installed it. From that point on unknowingly every time this engine ran it was dumping raw fuel through the choke prime into both carbs.

So, I did my diagnosis based and kept finding the top carb where ever it was placed seemed to be the problem. I had vacuum, reeds looked good, plugs x2 good but a bit wet (my bad for not seeing it as flooding instead of lack of fuel). So the chase was on.

All that being said it falls on me for not looking more deeply at you guy's help, not all pointed at this problem but as jimmbo said, "You guys can't see what I see."

Anyway, when jimmbo said this, "However, that said, the OP says the Engine didn't respond when Fuel was Sprayed into the Carb of the non-firing Cylinder... Maybe it is actually flooding the engine, not starving it." The light came on and I retraced each step in this issue starting at choke solenoid (Amazon) on through racerone's reply, "Spark plugs and even the air would prove that!"

Problem solved, (Amazon)!

Thank you all so much for taking your valuable time to guide me along with this. I guess it just goes to show ME that even though I've been diagnosing and repairing vehicles, boats, aircraft etc all through my life I can sure miss the mark when I don't see the obvious. Hey, I've got a nicely overhauled carb out of it. LOL

Thanks a ton,
mebehoof

 

[tphoyt]

Problem Solved !!!

A big Thanks to jimmbo, racerone and everyone except that one guy LOL you know who you are LOL.

The answer was in jimmbo's last reply and racerone's answer to that.

Here goes, as you all know when I first unwrapped and started the engine this Spring the Choke Primer was leaking so I bought one on Amazon (bad idea) and installed it. From that point on unknowingly every time this engine ran it was dumping raw fuel through the choke prime into both carbs.

So, I did my diagnosis based and kept finding the top carb where ever it was placed seemed to be the problem. I had vacuum, reeds looked good, plugs x2 good but a bit wet (my bad for not seeing it as flooding instead of lack of fuel). So the chase was on.

All that being said it falls on me for not looking more deeply at you guy's help, not all pointed at this problem but as jimmbo said, "You guys can't see what I see."

Anyway, when jimmbo said this, "However, that said, the OP says the Engine didn't respond when Fuel was Sprayed into the Carb of the non-firing Cylinder... Maybe it is actually flooding the engine, not starving it." The light came on and I retraced each step in this issue starting at choke solenoid (Amazon) on through racerone's reply, "Spark plugs and even the air would prove that!"

Problem solved, (Amazon)!

Thank you all so much for taking your valuable time to guide me along with this. I guess it just goes to show ME that even though I've been diagnosing and repairing vehicles, boats, aircraft etc all through my life I can sure miss the mark when I don't see the obvious. Hey, I've got a nicely overhauled carb out of it. LOL

Thanks a ton,
mebehoof

Great news. Time to go fishing and two thumbs up for Jimbo.

 

[saltchuckmatt]

Hmmm..... talking about me?

Anyhow, I'm sure it's nice to have it up and running again, congrats.

"Spark plugs and even the air would prove that" now who did you think said that?

Best,
Matt

 

[mebehoof]

Hmmm..... talking about me?

Anyhow, I'm sure it's nice to have it up and running again, congrats.

"Spark plugs and even the air would prove that" now who did you think said that?

Best,
Matt

Matt, looking back over the posts in this thread, you did, and racerone was a repeat.

Thanks again all !
mebehoof

 

[saltchuckmatt]

We have a summer home on Puget sound near Seattle Washington....the other Washington. I often walk the beach and see people destroying their arms trying to start their outboards, the smell of gas permeating the air. You walk up and the choke is on and they have their partner pumping the primer.

I push in the choke, turn the handle to as low as it goes.....unplug the fuel line and 15 to 20 pulls later it sings!

Sine people just weren't made small engines.

 

[Crosbyman]

as the world population grows there is less and less intelligence to share...
and lots of folks can't even read .

 

[racerone]

Agreed----Most folks are limited to pushing buttons.-----If there is no button to push folks are stumped.-----Common sense often does not exist.---.------Folks even need a monitor / warning to keep track of oil in their vehicles.

 

[saltchuckmatt]

Yes the dip stick is dying or should I say the dip ****'s are everywhere.

 

[ct1762@gmail.com]

ive seen those knockoff primers on Amazon and the reviews are horrible! glad i never actually bothered to test one out. go on ebay and get a crappy used one and rebuild with an OEM kit. they are damn near indestructible accept if moisture gets in them... and they usually still work!

 

[Geoffrey Graydon]

racerone,

Amen to that Sir! I'm pouring over YouTube and any info I can find to try to understand things 2 stroke.

Question: on this 40hp Johnson is the crankcase common, i.e. shared by both cylinders or partitioned so each cylinder has its own fuel/air ?

Also, as I mentioned in a couple of posts, I was wrong, the top cylinder suction when running is the same roughly as the lower cylinder. Lot to learn.
mebehoof TIA

I know this may sound silly but have you considered changeing the spark plug on that cylinder.