Starting Trouble Honda GX-340

P

PGB1

Active Member
Hi All,
I have a Wacker generator with a Honda GX-340 Type VWC2 engine. It used to always start on the first partial pull of the recoil starter rope. I run it every 3 months with fresh gasoline. When done, I run it until it stalls for lack of fuel. I also pull the rope until fir resistance is felt, hoping the valves are closed. The oil is changed each 6 months regardless of hours (or 50 hours of run time).

Suddenly, it is difficult to start, or does not start.

First, I put in new spark plug. This did not help. Later that day, it would start and run fine. It would re-start.

Then later, no start which is the current status. I tried starting fluid in the throat of the carburetor and no start. I have a spark tester of sorts. It is a pointed metal rod with a 0.116" gap to a flat metal surface. This shows a rather weak & yellow spark.

Am I correct is thinking the ignition coil may be faulty?
Is there a way to test the coil? (I saw all kinds of science project methods on line ranging from hitting it with a hammer while using an Ohm meter to hold a finger on the plug wire while pullling the rope.)

What else should I examine?

Thank You All Very Much for helping me learn & fix this engine. I appreciate it!
Paul
 
is there gasoline in the oil? If so it is too rich.

Have any critters moved in, peed on the wiring, chewed it?

Maybe rust is bridging the coil gap and weakening the magnetic field. The easy fix is pull the shroud cover, compressed air around the coil and flywheel, and double check the air gap. There was one program that James Condon worked on one where the bolts holding the coil on got rusty do the coil was very poorly grounding. Those bolts are soft and break easy. Use real penetrating oil on them if they seem too tight or are rusty.

That said, new fuel as in new to the engine or new to you? Could it have a little moisture in it? Maybe drain the carb bowl into a clear cup or glass and see what the fuel looks like.
 
If it wont fire with ignition fluid , you have an ignition problem , clean up the coil and flywheel area with some emery paper , pull the plug and ground to watch for a spark , should be good healthy spark not weak, if you don't see anything, -- I hold the coil wire and pull the starting rope and see if I fell a " shock " in my hand - Just my own test , it should make your muscles jump, then work from there.
 
Thank You all for taking time to reply & offer suggestions,. I wanted to check in to let you know that I appreciate your help and have not been able to work on the engine yet. (Life's demands got int he way) Hopefully I can update soon.
 
PGB1 said:
I run it every 3 months with fresh gasoline.
Click to expand...
So you drain the ENTIRE fuel system every three months? Replace with fresh non E-10 gas? I'd recommend using Stabil fuel treatment. The old school recipe not the new 360 or marine Stabil versions.
PGB1 said:
When done, I run it until it stalls for lack of fuel.
Click to expand...
So the carb needle and seat, sit, with no fuel and dry out for months? See where this is going? If the needle tip is rubber, it will go sour and not seal.
PGB1 said:
The oil is changed each 6 months regardless of hours (or 50 hours of run time).
Click to expand...
Perfect. All your cars and trucks should have the same treatment. Twice a year regardless of mileage. Oil is cheap. Engines not so much.
PGB1 said:
First, I put in new spark plug.
Click to expand...
WHERE did you get this from? Amazon or fleabay? If so plugs are highly pirated. Best to buy from a local auto parts store. If it says Torch on it, trash it immediately.
PGB1 said:
I tried starting fluid in the throat of the carburetor and no start. I have a spark tester of sorts. It is a pointed metal rod with a 0.116" gap to a flat metal surface. This shows a rather weak & yellow spark.
Click to expand...
Here is a good tip to investigate. Weak spark. Open gap spark testers are the best. Can stress out the coil compared to the light bulb type. Recommend non resistor plug/s. Spark needs to be blue or purple. Test with near zero light for spark length and color.
PGB1 said:
Is there a way to test the coil? (I saw all kinds of science project methods on line ranging from hitting it with a hammer while using an Ohm meter to hold a finger on the plug wire while pullling the rope.)
Click to expand...
No. Only an open gap spark tester. Here is one for $1.39 delivered to your door.


1778078964217.png
 
slomo said:
So you drain the ENTIRE fuel system every three months? Replace with fresh non E-10 gas? I'd recommend using Stabil fuel treatment. The old school recipe not the new 360 or marine Stabil versions.

So the carb needle and seat, sit, with no fuel and dry out for months? See where this is going? If the needle tip is rubber, it will go sour and not seal.

Perfect. All your cars and trucks should have the same treatment. Twice a year regardless of mileage. Oil is cheap. Engines not so much.

WHERE did you get this from? Amazon or fleabay? If so plugs are highly pirated. Best to buy from a local auto parts store. If it says Torch on it, trash it immediately.

Here is a good tip to investigate. Weak spark. Open gap spark testers are the best. Can stress out the coil compared to the light bulb type. Recommend non resistor plug/s. Spark needs to be blue or purple. Test with near zero light for spark length and color.

No. Only an open gap spark tester. Here is one for $1.39 delivered to your door.


View attachment 73233
Click to expand...
I'm kind of compulsive about fresh fuel for small engines. Every 3 months & after every running, I drain the entire fuel system, including carburetor. First I run it until it stalls for lack of fuel.Every 3 months I put the gas can gas in the car and buy new for the cans. I add Star Tron stabilizer to the cans. The cans are air tight. The gas is E-10. No place around here sells non-alcohol gas. (One would think they did because this is a big area for classic cars.)

You mentioned the needle tip drying out. Should I leave gasoline in the carburetor between uses? I do run my small engines every 3 months if they have not been used, so the gas won't get very old. (Not sure if I am having fuel problems. When it starts, it runs fine.)

The spark plug is from a lawn equipment store. It is NGK brand.

That is a nice looking tester that you linked. Mine is essentially the same, but it's not covered in a cylinder like the one in the photo.
 
Last edited:
Oddjob said:
Does it have a sensor to ensure adequate oil? Many generators do. That sensor could be failing but first check your oil level.
Click to expand...
How does one test the Low Oil sensor?
It has a module with two wires coming from it. One wire goes to the ON-OFF switch and the other goes to a probe that is screwed in the crankcase.

When wires are disconnected, should the probe show continuity to the engine frame?
Should the module show continuity between wires, or show Open?

I am guessing, but only guessing, that the sensor is OK because I get a spark with the spark tester. It is a weak, yellow spark- but something.

Hopefully this evening I can start investigating the engine.

Paul
 

Attachments

  • Module.png
    Module.png
    582.2 KB · Views: 3
PGB1 said:
You mentioned the needle tip drying out. Should I leave gasoline in the carburetor between uses? I do run my small engines every 3 months if they have not been used, so the gas won't get very old. (Not sure if I am having fuel problems. When it starts, it runs fine.)
Click to expand...
I use stabil year round. Every can of gas gets stabil. Never have to worry about when I bought it being old and stale. Fuel lines and carb needles don't dry out and must be replaced...... Yes leave the stabil treated fuel in the carb. Let the stabil work for you.

I used to drain all my machines over the winter. Had to replace a lot of lines on trimmers and such, seemed like yearly. Started leaving treated fuel in over winter. No more buying fuel lines since. Get many more years from them.

Best to top the tank off leaving no air to make condensation. Store mower in the garage.
 
You must log in or register to reply here.
Back
Top