Subaru Robin EX17 wont start

[gunlvr1974]

I have tried everything I know. I have fuel, I have fire, I have air. I have replaced the coil. plug, and electrical connectors. I have checked continuity of all my wiring. Still dead in the water when I pull the rope. I have tested the kill switch, and the main key on the go kart dash. All good, but still no fire. Help!!!

 

[mckutzy]

Hello and welcome...
Can you post of few pics of how you have the throttle setup and also what mods did you do to it???

 

[Brianator]

Did it just stop starting one day or has it been sitting for awhile?

 

[landuse]

Pics would help a lot

Seeing as it doesn't want to start, it can only be three things. Fuel, spark and air (or compression.

Take the plug out and pour a teaspoon full of fuel in there. Put plug back in and pull. Does it run for a few seconds? You can also spray starter fluid into the intake. Does the engine stutter a bit and run for a second? If it does, it sounds like you are having a fuel issue. The fuel is just not getting to the spark. I would give the carb a good clean again, even if you have already.

Change plugs too....that sometimes helps

 

[gunlvr1974]

EX 17 Won't start

I will post pics when I get home today.
It just stopped being used. No issues before hand.
It has a new carb.
I have tried starter fluid and I get no fire of any sort.
It has a new plug and coil.
And there are no mods of any sort. It is just a FOX Vector Go Kart with a Subaru Robin motor.

 

[gunlvr1974]

Added pics

Added pics from my kart.

 

[Brianator]

Theres a possibility the piston rings are stuck in the piston essentially lowering compression. How does it feel when you pull the cord?

 

[gunlvr1974]

It feels normal when I pull the rope. If they were stuck what would it feel like?

 

[Brianator]

It would feel slightly easier to pull through the compression stroke than it should, its hard to explain I guess. I once fought with a free gx160 that would "cough" and wanted to start but wouldn't... then it started wanting to start more and more and would actually run for a few revolutions (this went on/off for 3 days btw). Then one time it fired up and ran so I kept it running for awhile varying the throttle every now and again and it now starts and runs fairly easily. My theory is that the rings were stuck but once the motor finally caught, the combustion pressure popped the rings loose (with the help of the penetrating oil that had soaked in) and I can feel the slight difference when pulling it over now. Might not be your problem but rings CAN stick

 

[gunlvr1974]

Well the piston is moving freely. Doesn’t seem to be stuck. Tomorrow I’ll try putting fuel directly in and see if I get fire.

 

[mckutzy]

You said new coil and plug....
What was the air gap set to?

 

[Brianator]

The rings can get stuck in the ring lands (grooves) of the piston and not to be confused with being seized to the cylinder wall. When that happens compression can and will make its way past the rings effectively lowering compression and if you don't have enough compression she won't run. When the fuel/air combusts a little pressure gets into the ring gap and expands the rings into the cylinder wall which holds more of the compression in the cylinder. It's one (big) reason why a properly broken-in engine will outperform one that was just started and used in both the performance and longevity departments.

 

[gunlvr1974]

ex17 wont start

Ok, I will work on freeing up the piston rings this weekend and see if that makes a difference. Thanks.

 

[Brianator]

IF its the issue, you just never know....

 

[gunlvr1974]

So I put some fuel in the plug hole. Still no fire. Carb is new. Plug is new. Coil is new. Now what???????

 

[mckutzy]

Like I said, what is the coil gap?

 

[gunlvr1974]

The gap is at .012. But this coil is also not adjustable.

 

[Brianator]

What color is the spark when you ground the plug and pull the cord? Did you gap the plug to spec? Every magneto coil I've seen has SOME adjustment built into the mounting holes so I'd be surprised that yours doesn't but then again im not familiar with your engine although it does look like a Honda clone. Is the magnet clean and free of corrosion/ rust? That'll hinder spark and weak spark can "blow out" under compression.

 

[gunlvr1974]

I would say it is a white spark. Normally the coil does have slotted holes for the bolts but this one does not. So when it is mounted it is fixed where it is. I cleaned up the magnet to get all the rust off of it. I putt a little fuel in the spark plug hole and still didn’t get it to spit and sputter.

 

[Karts of Kaos]

is the flywheel key sheared?