RancherRider 2 Posted February 27, 2021 (edited) So I bought this a couple months ago used with 79 hours on it. Looks brand new. Has run perfect, then yesterday while way out on a trail I started it and hit the gas and just died down. Then crunk right back up but died. I noticed that I no longer would hear the fuel pump prime when I turned the key on. So I went in the fuse box (all fuses were good), and took out the single relay which I assumed ran the fuel pump. So after taking it out fiddling with it and putting it back in, I turned the key and heard the fuel pump turn on, so I jumped on and took off! My question is, is that even the right relay for the fuel pump or was that just a coincidence? Or do you think this ATV is old enough that the previous owner could have left it sitting with ethanol gas in it and destroyed the fuel pump? I have run only non-ethanol through it, but maybe only half a tank so far. I can post a pic of the relay. Thank you Edited February 27, 2021 by RancherRider Share this post Link to post Share on other sites
_Wilson_™ 6,593 Posted February 27, 2021 welcome to the forums. does it have the same battery ? or has it been replaced with a new one, or the old load tested ? if you could post some pics (yes) that would be helpful. Share this post Link to post Share on other sites
retro 4,073 Posted February 27, 2021 Hi RancherRider, welcome to ATV honda! It's impossible to guess for sure, whether the fuel pump is going bad already, or if the pump relay is going bad, or if the relay has a poor connection in the harness connector? Any of those could be possible... so unless you have access to a fuel pressure gauge for testing the pump right away, If I were you I would assume that it is still good and instead do a bit of preventive maintenance on it right now, by unplugging the pump relay for a dielectric greasing, then ride it. If the same thing happens again in exactly the same way, then you'll be clued in on the relay being the most likely problem. Keep us posted and congrats on getting yourself a new Rancher! Share this post Link to post Share on other sites
RancherRider 2 Posted February 27, 2021 Thank you for the quick replies guys. Here is a picture of what I assumed to be the correct relay, the fuse box where it's located, and the battery. The manual describes the identity of each fuse, but not the black relay. I'll def hit it with the dielectric grease before returning it. From your experience do the relays just die, or do they go in and out before dying? I have a multimeter, I going to look up how to test one, never done it before. I'm just hoping this is what it is, because I'm not real excited about pulling the fuel pump out. Edit: I just found it on a parts diagram and it says DIODE ASSY., THREE WAY (SUMITOMO) 31730-MAS-601. So maybe it's not a relay at all. It listed several other actual relays but did not define them. 1 Share this post Link to post Share on other sites
RancherRider 2 Posted February 27, 2021 10 hours ago, _Wilson_™ said: welcome to the forums. does it have the same battery ? or has it been replaced with a new one, or the old load tested ? if you could post some pics (yes) that would be helpful. YTX14-BS is the exact battery it listed on the parts diagram, which this one is. I can't be sure if this is the original, but it doesn't seem to lag on the power output at all. No hesitation on starting. 1 Share this post Link to post Share on other sites
Tim-ANC 202 Posted February 27, 2021 Has anyone got hands on the newer 420 service manuals yet? I have a 2020 420 also. Latest model I've seen in the library is 2014. Share this post Link to post Share on other sites
Scotticus 777 Posted February 27, 2021 2 hours ago, Tim-ANC said: Has anyone got hands on the newer 420 service manuals yet? I have a 2020 420 also. Latest model I've seen in the library is 2014. I also have a 2020 Rancher. As far as I know 2014-2021 is the same. I have a manual for 2014-2019 that is 229 MB which is too large for me to post. I would be happy to share it if someone gives me some direction on how to do it. 2 1 Share this post Link to post Share on other sites
Tim-ANC 202 Posted February 27, 2021 Top of the forum board is a link to a gdoc with manuals. Maybe you can upload there? Share this post Link to post Share on other sites
Melatv 797 Posted February 27, 2021 Hi: If you touch the throttle when starting the bike --- it will shut down and the bike will time out for a short time before you can start again. safety feature so the bike will not take off if in gear. 1 Share this post Link to post Share on other sites
retro 4,073 Posted February 27, 2021 1 hour ago, Scotticus said: I have a manual for 2014-2019 that is 229 MB which is too large for me to post. I would be happy to share it if someone gives me some direction on how to do it. Tagging @balljoints., for assistance with an FSM donation. Thanks for offering to share @Scotticus! If either one of you need a site to upload/download the PDF hollar at me, y'all are welcome to use my personal webserver to make a transfer. Share this post Link to post Share on other sites
RancherRider 2 Posted February 27, 2021 So just an update for anyone interested. Haven't really messed with it anymore, but did turn the key on without that diode in place and got no power at all. So that tells me it's not why the fuel pump was not coming on. It's something else. Makes me think that once the fuel pump has been running for a while it starts doing this shut down, because the other day once I had let it sit for a minute it started working again. Either that or by taking that diode out it did some sort of reset... idk. Gonna be nice tomorrow so I'm gonna ride it hard and see if I can get it to do it again. Share this post Link to post Share on other sites
Fishfiles 20,147 Posted February 28, 2021 Hi RancherRider , I have seen my Can-Am buddies have fuel pump problems when they get just a little bit of water in the fuel , I have watched them drain their tanks , go to O'Riely's and change the pumps here in my yard , they use a fuel pump out a Mazda car that matches up perfect , so if it comes down to the fuel pump , I would bet your 420 pump will match up to a automotive pump also , those pumps are pretty expensive , would bet a 420 is around $200 , seem to remember a Mazda pump can be had for around $40 --- there are a few different ways water could get in the tank , condensation , fueling from a dirty can, going under water or a bad cap 2 Share this post Link to post Share on other sites
retro 4,073 Posted February 28, 2021 You are right, that diode has nothing to do with a possible fuel pump or relay failure. That diode prevents flyback voltage spikes that the starter solenoid produces (when the motor starts and you stop cranking the starter, a high voltage is released by the electromagnetic coil inside the starter solenoid) from damaging the sensitive ignition ECM and the PCM-FI modules. The diode prevents those stray high voltage spikes from returning by cutting off conduction. A diode functions similar to a one-way valve to provide protection for sensitive electronics, in that electrical current is allowed to flow through a diode in only one direction, but current is not allowed to flow through a diode coming from the opposite direction. 43 minutes ago, RancherRider said: Makes me think that once the fuel pump has been running for a while it starts doing this shut down, because the other day once I had let it sit for a minute it started working again. This is a fairly common complaint with 420 fuel pumps. They've always been weak and failure prone ever since the 420 Rancher introduction in 2007. But,.... yours is a 2020 model with very low hours of run time on it. The fuel pump is still so new.... I would suspect that a new fuel filter might solve the problem, before I'd jump to blame everything on the pump. As I mentioned though, 420 pumps are known to be problematic and generally have shorter lifespans than other pumps do, so I wouldn't rule the pump out either. More than likely it needs a new fuel filter. OR, a new pump & new filter both. So if I were you I would replace the fuel filter and see if that fixes it. If not, then go back in and replace the pump. Thanks for sharing what you've learned! 1 Share this post Link to post Share on other sites
balljoints 163 Posted February 28, 2021 17 hours ago, Scotticus said: I also have a 2020 Rancher. As far as I know 2014-2021 is the same. I have a manual for 2014-2019 that is 229 MB which is too large for me to post. I would be happy to share it if someone gives me some direction on how to do it. Can you upload to drive.google.com and send me the link, I can add to our huge stash of manuals, pm me if you need help on doing that! 3 Share this post Link to post Share on other sites
Scotticus 777 Posted February 28, 2021 3 hours ago, balljoints said: Can you upload to drive.google.com and send me the link, I can add to our huge stash of manuals, pm me if you need help on doing that! Uploaded the manual and sent you a PM with a link to google drive 8 Share this post Link to post Share on other sites
balljoints 163 Posted March 1, 2021 She has been added! Appreciate it! 5 Share this post Link to post Share on other sites
retro 4,073 Posted March 1, 2021 'tis a dandy one too! Thanks guys! . 3 Share this post Link to post Share on other sites
jeepwm69 7,749 Posted March 1, 2021 Here's my suggestion. Take a short bit of wire with you with the ends stripped. If you have the issue again, run that wire as a jumper from battery + to red/black wire on the coil. If it starts, your fuel injection relay back in the battery compartment is likely the problem. If it doesn't, it's probably the pump itself, or filter. If you use ethanol gas in these 420's and let them sit, it will seize up the fuel pump/ cause premature failure. It gums them up. 3 Share this post Link to post Share on other sites
toodeep 1,760 Posted March 1, 2021 Certain 2019 models had a fuel pump update because of faulty parts but since yours is a 2020 that shouldn't be an issue. The relays up up under the tank cover on these machines. It's possible the relay stuck and unstuck while you was messing around. Same could be said with the fuel pump. That's not the original battery so this machine sat for a length of time so the fuel issue at the pump is a possibility. It's hard to narrow down the problem when they are working but just a simple test light you can check to see if the pump is getting power when/if it dies again. No power, then test the relay and if your getting good power/ground the pump would be the problem. 2 Share this post Link to post Share on other sites
RancherRider 2 Posted March 1, 2021 Thanks everybody for being so helpful. A lot of good info. I rode it yesterday for a couple hours and no problems, trying to run some of the fuel out but it hasn't even dropped a bar. I'm going to carry a multi meter with me when I ride it incase it does it again. But it just seems so probable that the previous owner let it sit with ethanol gas in it, especially with toodeep saying that wasn't the original battery. So I just got to know what that fuel filter and pump look like. I'm going to go ahead and buy a new filter and get around to pulling the pump to assess it. Is there a possibility of cleaning the pump? Anybody have a favorite video to goes through the pulling and inspection of the fuel pump? Share this post Link to post Share on other sites
Fishfiles 20,147 Posted March 1, 2021 This video is a 2014 , the 2014-2021 should all be the same 1 Share this post Link to post Share on other sites