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

[Wonkydonkey]

Does this model have a wire mesh spark arrestor in the muffler? A plugged up screen may also give similar symptoms.

Yeh I said this, as well as someone else earlier in the thread said it could be bees/mud pluggers.

It would be easy to test and fix, but also PDX man tried earlier/to start on full throttle, if it were a clogged screen, you'd have thought it would have fired up briefly, but it didn't.

Two bolts, pop the exhust off and see if it will start.
Cheers

 

[Fish]

No, could be a loose valve seat, bad or sticking valve, hard to tell from here.......

 

[Fish]

Exhaust bolts/nuts don't always "pop" off all that easy....

 

[PDX Man]

Thank you all for your insights. I didn't have time to work on this today, but I can address a few of your comments. I certainly didn't take the flywheel off. There was rust on the coil and magnet, but I cleaned them with 150 grit sandpaper. I haven't touched the mixture screw at all yet.

I think my next step will be to do a more complete carb cleaning and then follow the advice about the mixture screw and then test again. And I'll review the videos and docs you have linked for me. I'll also look and see if the muffler looks like I could remove it without damage. Last time I tool a muffler off an old engine, it sheered the bolts off and I would have had to drill out the bolt holes to get it fixed.

 

[Fish]

Looking at it again, I have to put money on an intake valve problem...

 

[Fish]

What happened to the posts made in the last hour?

 

[backhoelover]

idk wait to see if he figures it out.

 

[PDX Man]

I'm afraid this mystery will never be solved. I stripped the spark plug threads putting in the spark plug. I'm off to harbor freight to buy a new engine.

Thank you all for your help. I learned a lot.

 

[Fish]

He just made a post saying that he cross-threaded the spark plug, and he was going to Harbor Frieght for a new engine!!
I put up sveral posts begging him to pull the head and find out what was wrong, if he was going to get a new engine.

Why are they all gone?

 

[Fish]

No, he made that post @ an hour ago, not the one just now.

I can understand that he deleted his post, but he deleted mine as well?

 

[Fish]

He needs to pop off that head, and let the world know what the problem is/was.

 

[backhoelover]

i would have went to napa and got a sav a plug kit. maybe he doesnt know about them

 

[PDX Man]

He needs to pop off that head, and let the world know what the problem is/was.

I guess that can't hurt now. What would I have to take off to take the head off? Would I have to take off the muffler. It looks like it wouldn't come off without a fight. The nuts look like they are rust/heat welded to the bolts. And what am I looking for once it is off?

 

[Fish]

I guess that can't hurt now. What would I have to take off to take the head off? Would I have to take off the muffler. It looks like it wouldn't come off without a fight. The nuts look like they are rust/heat welded to the bolts. And what am I looking for once it is off?

Looks like 4 bolts, and that is all, in many instances, one can leave the muffler attached to the head. This may be the blowup of your engine, I don't know the exact model numbers.

 

[CR888]

I bet it was something very simple making that Honda not run. I think in forums you get bombarded with so many possible causes to a problem, we forget to start with the easy stuff first. I for one would not be taking the flywheel off prior to inspection of a muffler screen etc. I don't think the carb is the problem given the evidence. Anyways at least he gave it a go.

 

[Fish]

 

[Fish]

I suggested that he go ahead and pull off the head and have a look, since he is going to get a new engine anyway. He then could drop off the head at a shop for a helicoil, if things worked out, and that was the way to proceed. Removing the valve head is very easy to do. Since this thread has had some views, the info for others in the wide world web would be valuable, and the OP would learn a lot as well.

 

[PDX Man]

I took off the head and all the valve parts. One of the 4 bolts is partially obstructed by the exhaust system, so I tried to remove the exhaust system, but the nuts are frozen and my 18V impact driver wouldn't budge them. So the partially obstructed bolt was difficult to get enough leverage to break it loose. Once I broke it loose, I could back it out enough to remove the head.

I'm not sure what everything should look like, but I don't see anything obviously wrong with any of the parts. No bent rods or valves, no scoring of the cylinder. I took some pics.

 

[Fish]

Can you get a closer shot of the valve faces/ Especially on the intake.
Pop them both back in the head, and pour some water in with your finger over the plug hole, see if the valves sitting there will hold the water some/any.

 

[PDX Man]

Can you get a closer shot of the valve faces/ Especially on the intake.
Pop them both back in the head, and pour some water in with your finger over the plug hole, see if the valves sitting there will hold the water some/any.

It holds water just fine. Here are some shots of the valve faces. The second and third pics have the valves rotated to show different sides.