Newbie looking for help with Honda GX240 that won't run

[Fish]

Have you ever checked the flywheel key?

 

[woodtool89]

well theres yer problem...the valves weren't even in the engine...howd all you guys miss that?
$12 carbonationator kit woulda saved this from becoming a $ .03 scrap pile, ohh well

 

[Fish]

well theres yer problem...the valves weren't even in the engine...howd all you guys miss that?
$12 carbonationator kit woulda saved this from becoming a $ .03 scrap pile, ohh well

Have you even read any of the posts?

 

[Fish]

I just looked at your past messages,
never mind responding.

 

[dall]

Have you even read any of the posts?

I have and you make sense
His posts not do much

 

[woodtool89]

I have and you make sense
His posts not do much

yup...look back and see who mentioned a look at a highly unlikely sheared key...
having the op tear this thing apart when all signs pointed to a carb issue from the get go, is what don't make sense...

 

[Fish]

So flaming backfire is a common carb problem eh?

 

[woodtool89]

So flaming backfire is a common carb problem eh?

that wasn't a constant symptom...it only happened when he was dumping gas down the intake!
the engine ran in multiple videos, it idled normal in the original video until the throttle was opened...a valve issue would have been noticeable even when idling...and wouldn't have died as soon as the throttle was opened, it would have sputtered and try to stay running at the higher RPM.
idk how you guys rule out the carb when A the original was never thoroughly cleaned or adjusted, and B then the cheap AM carb was installed straight out of the box with zero adjustment being done...you really think those cheap carbs come tuned from the sweat shop they're made in?

 

[Fish]

So, in your vast experience, has a flaming carb ever been a carb problem?

 

[Fish]

Hey, we're making progress, at least you have made 2 somewhat intelligible posts now on this site,

things are looking up in that regard.

There are a large number of questions unresolved, and a lot of suggestions made by members here, trying to help this guy discover what the problem
may be.
My suggestions have been more of the explore and observe route, not telling him to spend/waste any more money, but look at all of the possibilities.

What have you suggested? Buying a new "carbonater kit"? Adjusting the new aftermarket carb?

In the end, I finally suggested that he go ahead and pull off the valve head AFTER he had stated that he was giving up and getting a new engine. And even so, removing the head for a thread repair would be next anyway.
He got a little excited and removed the valves too, but hey, he lives on the other side of the country.......... Hard to do much from here......

 

[Fish]

BTW, a common practice of diagnosing small engine problems is putting a dribble or spray shot of fuel directly in the intake {not a pour}, and a flaming backfire is not something that a problem carb would cause, but would be a clue leading in other directions.

A sheared flywheel key is still another open possibility,
what are your suggestions?

Please, give a suggestion to ADD to the thread, not say something nasty and incoherent,
and put up stupid moving smileys...

 

[PDX Man]

BTW, a common practice of diagnosing small engine problems is putting a dribble or spray shot of fuel directly in the intake {not a pour}, and a flaming backfire is not something that a problem carb would cause, but would be a clue leading in other directions.

A sheared flywheel key is still another open possibility,
what are your suggestions?

Please, give a suggestion to ADD to the thread, not say something nasty and incoherent,
and put up stupid moving smileys...

A sheared flywheel pin would mean the flywheel spins on the shaft, right? It doesn't by hand, anyway, I can't turn the flywheel on the shaft. Or could it mean that it is stuck on the shaft at the wrong position? If I need to check that, what would I need to remove? I couldn't find any videos on youtube covering this.

 

[Fish]

If you have access to an impact wrench, just zip off the flywheel nut, and look and see if you can see the keyway and key.

 

[PDX Man]

A sheared flywheel pin would mean the flywheel spins on the shaft, right? It doesn't by hand, anyway, I can't turn the flywheel on the shaft. Or could it mean that it is stuck on the shaft at the wrong position? If I need to check that, what would I need to remove? I couldn't find any videos on youtube covering this.

I took the fan off and got a look at the flywheel key. It doesn't look like it has been sheared.

 

[Wonkydonkey]

So now the carb is clean, and it does not seem'do to have resolved the problem. Does it still tick over a bit with the throttle closed, have you open the fuel mixture screw out 1.5/2 turns.

I don't think its the flywheel key unless you taken the flywheel off and not put it on wrong. But it could be the key ?, it's an elimination process, Is there any rusty deposits in the flywheel magnets
But I'm now thinking it's the coil. Do you get a good spark on the spark plug,
Do you know anyone with a simular engine where you can swap/try your coil. In there engine.
And watch this

This is worth a read,
https://www.smokstak.com/forum/showthread.php?t=72156
They go over simular topics
It says could be spark screen, if you have one,
It says try running with the choke on a a little bit, as this increases the fuel air ratio

Everything I see/read says fuel, carb clean first, then spark/coil timing.

This youtube vid, shows removing flywheel after testing the coil and spark cap

 

[bill saf]

a weak valve spring with worn valve stems or guides will have the valve not seat SQ and would cause a backfire and would cause a stalling problem as back presser in to the intake man. I saw the pics of the valves the intake is seating closer to the outer margin then I would like to see it. the exh valve looks to have some carbon on the valve face that would cause popping from the exh. the OP's vid valve 2 at the 8sec mark after he grabs his phone I did hear some popping if some one would listen to the vid and tell what you may hear? I was going to say to put a compression gauge wipe on in the spark plug hole and hook up a compressor and listen for leaks at the intake and exh but I was to late threads gone 120 psi will have more leakage then water.

 

[PDX Man]

a weak valve spring with worn valve stems or guides will have the valve not seat SQ and would cause a backfire and would cause a stalling problem as back presser in to the intake man. I saw the pics of the valves the intake is seating closer to the outer margin then I would like to see it. the exh valve looks to have some carbon on the valve face that would cause popping from the exh. the OP's vid valve 2 at the 8sec mark after he grabs his phone I did hear some popping if some one would listen to the vid and tell what you may hear? I was going to say to put a compression gauge wipe on in the spark plug hole and hook up a compressor and listen for leaks at the intake and exh but I was to late threads gone 120 psi will have more leakage then water.

If I try to move the valves now, it seems like the intake valve is sticking a bit. I should have tried it before I did the holding water test, though. Here is a video.

 

[bill saf]

I just looked at your post #98 could you tell us if the center of the piston has a pin hole in it from the pic it looks like it could have one but I cant tell from the pic to be sure. the center of the piston has erroison and at the bottom theres a lite tan or white dot about the size of a pin

 

[bill saf]

Ok now we know that the intake valve is tight and sticking now it comes down to what you would like to do fix what you have or buy a new engine from HF.

 

[Fish]

Is is sticking because of some interference on the valve shank where it meets the guide. Any burrs or ridges?