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Honda Rancher 420 Crank No Start

Lee

Lee

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Pretend it's Tuesday.

2012 TRX420FA AT

I've got fuel. I've got spark. I've got compression. It'll run on carb cleaner.

It died suddenly in the field.

I didn't really diagnose anything. Just assumed it was fuel pump/ filter. I threw a new assembly at it. No change. I confirmed it's getting fuel to the injector. I confirmed the injector is getting a signal with a Bosch noid light.

There doesn't seem to be a way to check fuel pressure. Seems like it would at least start. It pumps a steady stream to the injector.

While I have not put a compression gauge on it. It blows my thumb off the spark plug hole with authority while cranking. It also has plenty of vacuum, enough suck your hand tightly shut to the throttle body while cranking.

It doesn't try to suck a blue shop towel up the exhaust so it's at least mostly in time.

I assumed bad injector. Just replaced the fuel injector and absolutely no difference.
 
Lee said:
Pretend it's Tuesday.

2012 TRX420FA AT

I've got fuel. I've got spark. I've got compression. It'll run on carb cleaner.

It died suddenly in the field.

I didn't really diagnose anything. Just assumed it was fuel pump/ filter. I threw a new assembly at it. No change. I confirmed it's getting fuel to the injector. I confirmed the injector is getting a signal with a Bosch noid light.

There doesn't seem to be a way to check fuel pressure. Seems like it would at least start. It pumps a steady stream to the injector.

While I have not put a compression gauge on it. It blows my thumb off the spark plug hole with authority while cranking. It also has plenty of vacuum, enough suck your hand tightly shut to the throttle body while cranking.

It doesn't try to suck a blue shop towel up the exhaust so it's at least mostly in time.

I assumed bad injector. Just replaced the fuel injector and absolutely no difference.
Click to expand...


You have spark, but is it a good strong spark? Any low oil safety thing? If you have air, spark and fuel it should pop.

How does the plug look? Is the plug grounding when installed maybe?
 
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i have an older version of that one from 2003. Does your have a CDI box or some sort of ignition management module? They go bad from time to time

Just because you have spark once doesnt mean you have continuous spark to keep it running.

edit: had a similar problem on a kawasaki and changed the ignition control module and it ran fine. until i gunked up the carb again.
 
condition of the battery? We have 3 of the same model in my neighborhood. They are EXTREMELY sensitive to low voltage. To the point that we keep them on trickle in storage.
 
Can you pull the injector out enough to see if it's spraying fuel :confused:

I had one for a decade, never any issues though besides the battery. it won't run below 12V.
 
rockota said:
condition of the battery? We have 3 of the same model in my neighborhood. They are EXTREMELY sensitive to low voltage. To the point that we keep them on trickle in storage.
Click to expand...

Yeah I've got two 12 and a 14, they've been dead nuts reliable until now. General maintenance and batteries. This battery was new this spring. If I remember right. I've cranked it so long that it's basically dead and have it on a jump box now.

Norm said:
Can you pull the injector out enough to see if it's spraying fuel :confused:

I had one for a decade, never any issues though besides the battery. it won't run below 12V.
Click to expand...

I'm not saying it's impossible but it will be difficult the way the injector mounts and fuel line mount to the throttle body.
 
Lee said:
Yeah I've got two 12 and a 14, they've been dead nuts reliable until now. General maintenance and batteries. This battery was new this spring. If I remember right. I've cranked it so long that it's basically dead and have it on a jump box now.
Click to expand...

Found that on all 3 of ours, if the battery is a bit weak, it doesn't even like to shift out of N. All 3 of us were complaining about it one day... turns out all of us had "weak" batteries.
 
Lee said:
I assumed bad injector. Just replaced the fuel injector and absolutely no difference.
Click to expand...

From what you've said, the only thing it could be is a fuel issue. I'm surprised to hear that it has a new injector but still won't run.

It may be worth doing what Norm suggested to verify if you're actually getting fuel out of the injector. It may save you going down a lot of other rabbit holes.
 
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