jeepwm69

Welcome aboard. If you go to the "service manuals" at the top of the page, click the links to download the service manual. Section 4-8 and 4-9 have the error codes. There is no code 4, but there is a code 44. Is your cooling fan on as well?

I had a new 2nd/3rd gen I sold a couple of weeks ago for $800. Buyer was willing to pay $900, but I'd had it listed at $800 so I honored the ad (he offered extra for me to ship it). Sold it pretty quickly. I think the guy that mods those to fit a 1st gen charges a couple of hundred bucks minimum to do it, so this really isn't a bad deal if you really want one.

That's pretty cool. Reminds me of the truck in The Road Warrior with that front bumper.

So, this might be a stupid question, but I’m starting to think I have burned/melted wires in the harness somewhere. Is that what you electrical experts are leaning towards? I’m eyeing this https://www.ebay.com/itm/256307769169 Since the CKP test looked ok, safe to say the problem should be in the harness/ECU?

Pretty sure that one is toast. I’ll let @AKATV chime in though. The good thing is, new Rincon meters are still available from Honda.

I wasn’t much help, but thank you for posting the fix! Should help someone out in the future

I bought some 300 gaskets from them. They are not OEM but were good gaskets. I still need to call you back. Had a day from ! at work yesterday and I’ve been driving all day today headed to the in-laws for spring break.

https://www.ebay.com/itm/174113245915?itmmeta=01HS286R1NAMGRANSFCV826BSS&hash=item2889f54adb:g:1fEAAOSwxcJd5Gcg&itmprp=enc%3AAQAIAAAAwNEeWJP8PnT1rzAID%2BSufpwlT%2BxdQjYkIi1PEO6%2F5o1oqNtWdcGlPslenQgSQc1zlW%2FfroheW2K1PRUFoh9CP3ZpCqXABlMVrsDxlVXb9H9RuL72suQql0IvoZU%2F9ieZpELtvNHiJd0xA%2F3iSrcVOOsZqhxfblZ43D1CoXIX3UHkqTgaYCeRoezeQq40RTJV0DsDt5qp1lE5Vpj9LAurkwXIBeip7JE7ANv7zTa45GgJQCzIGc%2BJ2Aku%2FzYVnxvHeA%3D%3D|tkp%3ABk9SR_qAm8jIYw lets get your shifting fixed and then we can focus on the neutral switch

So, zooming in on this pic on my computer at work, much easier to see. You see the yellow/blue wire that I spliced using one of those heat shrink tubes with solder in the center. That was a wire that was completely gnawed in two by a rat, which is why the wheeler was originally brought to me. I fixed three such wires, wheeler ran, and I returned it to the woman. A couple of weeks later she called me back, wheeler was dead again. I discovered blown ignition fuse, and when I replaced the fuse, the coil smoked and hissed, and I realized the coil wire had melted to and was shorted on the exhaust. I have not found any more wires gnawed in two, and the woman moved the wheeler from a barn to her carport when I returned it to her the first time. So should I snip. strip, and reconnect the wires that were gnawed but not broken to make sure they have a good connection? Replace the whole harness?

Yep, that's exactly the problem I found on the 500 I linked to above. I'd check that. Not a terrible job to look under the front cover since you don't have to pull the engine.

Misery loves company......

I see what you’re talking about now. Green wire gnawed on. Am I better off snipping those and stripping them back and getting a better connection? i’m fairly certain that the rat damage was done before the coil wire melted

That was the initial problem was rat chewed wires. I used some of those heat shrink connections with solder in the middle to put the wires back together. Machine ran until the aftermarket coil wire melted on the exhaust.

No voltage at the coil with that gray plug disconnected. Plugged it back in and coil reads 10.95 V battery reads 12.33v So are y’all thinking this is my problem?

Yeah, that's my buddy's that I borrowed last week to try on that Foreman I'm working on. I took pics of the wires to makes sure I put it back the way it was supposed to be.

Green wire on green tab.

Green on a Honda is almost always ground. On the coil, the black/red wire is + and the green wire is -

Well the only one of these I've torn down was about 10 years ago, and I honestly don't remember. I am fairly certain the front cover comes off, then there are a couple of more bolts holding the spacer on, but I can't be certain of that.

Sounds similar to what I have going on with the 2013 Foreman with no spark. (which is pretty much a 420 with a bigger jug on it)

Well this is @basfnb's, so I ordered one off of ebay. I have two of these in the yard, but didn't want to tear down an engine for a $30 part (got the whole input shaft with all the gears). And the afternarket cylinders, pistons, rings, etc have all dried up for these! Hopefully it's temporary, but it's all unavailable now! Nuts! Gaskets are no problem, but the others bits are unobtainium.

You can download the factory service manual free in the toolbar at the top of the forum. It's under "Service Manuals" button. This is a 2016, shows some details on what's under the front cover starting at about the 2 min mark. The 420's really haven't changed over the years.

So # 19 in this schematic? https://www.partzilla.com/catalog/honda/atv/2011/trx420fa-a-fourtrax-rancher-at/gearshift-fork My guess is either #18 is broken, or the spring fingers are not straddling it. Unfortunately no way to know without pulling the front cover.

You should be able to shift gears with the machine off. If you can’t you probably have problems with the shift linkage under the front engine cover. Lets look into that first. If you’re stuck in gear my guess is it is something similar to this

Welcome aboard. Is it an FA (auto/ ES with independent rear suspension) or a 420 FE (ES, or manual electric shift on handlebar)?