[BeCoulter79]

Hello all, I'm new to the forum and have been searching for a few hours to figure out what is wrong with this rancher.
I bought the rancher yesterday for my son and was told that the top end had just been redone and bored1 over. I rode the bike for a while at the seller's home and so did my friend, with no problems. I brought it home and rode it for 30 minutes or so and several other times throughout the day. My son rode it for the first time today for 30 minutes and then parked it and let it idle for about 5 minutes. when he got back on it and took off it acted like it was running out of gas. I checked and made sure he had turned the gas on and it was on. I was able to limp it to the barn but it had very little power. Once back at the barn I changed the plug and it did help some but it is still back firing through the carb at half throttle. The seller told me he had recently cleaned the carb and that he had been running it around his farm without issues. I filled it up with gas yesterday and that is all I had done to it until it quit running correctly. I'm guessing the carb could be dirty but it just seems weird that it started having an issue all of a sudden, I hoping you folks might have a few suggestions to start with tomorrow when I start on it again. I did spray some carb cleaner in when it started to run badly trying to see if it was starving for fuel.

thanks ,

 

[mcraejcrr]

Hello all, I'm new to the forum and have been searching for a few hours to figure out what is wrong with this rancher.
I bought the rancher yesterday for my son and was told that the top end had just been redone and bored1 over. I rode the bike for a while at the seller's home and so did my friend, with no problems. I brought it home and rode it for 30 minutes or so and several other times throughout the day. My son rode it for the first time today for 30 minutes and then parked it and let it idle for about 5 minutes. when he got back on it and took off it acted like it was running out of gas. I checked and made sure he had turned the gas on and it was on. I was able to limp it to the barn but it had very little power. Once back at the barn I changed the plug and it did help some but it is still back firing through the carb at half throttle. The seller told me he had recently cleaned the carb and that he had been running it around his farm without issues. I filled it up with gas yesterday and that is all I had done to it until it quit running correctly. I'm guessing the carb could be dirty but it just seems weird that it started having an issue all of a sudden, I hoping you folks might have a few suggestions to start with tomorrow when I start on it again. I did spray some carb cleaner in when it started to run badly trying to see if it was starving for fuel.

thanks ,

I am wondering if by chance when you filled it up with gas that something may have stirred up from the bottom of the tank and may be obstructing the fuel petcock, line or possibly the float needle. I would ensure that you have gas at the float bowl by cracking the drain screw and then move to checking the carb internals for debris. May not be the issue but it would be a place to start. Could potentially need the valves adjusted if it is backfiring through the carburetor but that is a little more tedious if you haven’t done it before. Wish you luck and keep us posted.

 

[Goober]

Like I mentioned to fellow earlier, your carb probably needs rebuilt. Cleaning isn’t enough if your seals are brittle.

Download the service manual from the link in my signature block below

Verify the carb on your quad is the OEM model (service manual). use the oem parts finder at Rocky Mountain atv and partzilla. Don’t buy aftermarket carb!!

Here’s a pic of a TRX300 carb; now it’s different than yours in a few ways so if you want to try rebuilding it:
Buy a genuine Shindy or K&L rebuild kit.
Buy an oem choke (SE) valve.
Buy an oem primer plunger.
We can help you thru the rest
the primer plunger alway seems to like to fart dirt right into the jets.

 

[BeCoulter79]

Thanks, Guys, I was wondering about gas also. I will start with a carb rebuild, the seller just said he cleaned it. if that does not fix it and the valve needs adjusting I will have to take it somewhere.

I will keep you posted and thanks for the help,

 

[Goober]

Good call—but check to see if you have OEM carb on it Honda may not work on aftermarket

 

[BeCoulter79]

Good call—but check to see if you have OEM carb on it Honda may not work on aftermarket

I ordered the whole carb. thanks for your input.

 

[Goober]

Drain all old fuel and inspect tank with flashlight. Try not to get old fuel or seds in new carb.

synchronising carb can be aggravating

setting valves is not hard but you do need special tools and experience.

Try rebuilding old carb

 

[Kiwi21]

If it idles but has no power, I would imagine the main jet is plugged. The idle jet is working but not the main. Probably stirred up some junk in the tank, especially if it’s been sitting a while. So, I would drain the tank, check it. Check the fuel filter, and remove the carb and just pop the float bowl off, check both idle and main jets, but before you. Remove the idle jet, count the number of turns it is set at from fully in and make a note of that. Pull the jets, inspect and clean, and reinstall. I’d be willing to bet you are fine. If the gas was bad you would have major issues getting it started, and my experience with ethanol gas is that when it’s bad, often times the engines will not start at all.

Back firing through the carb could be a result of a plugged main jet also, but could also be a stuck inlet valve. Might beg a good idea to check the valve clearances and watch the inlet valve open and close As you turn the motor with a wrench through the nut at the back of the transmission.

If the engine was recently worked on, it could be the valve clearances weren’t locked down properly and the adjustments have shifted.

 

[Kiwi21]

Btw the valves are easy to adjust. Just a bit fiddly, that’s all. I did my 2012 420 TE the other day, as part of the annual maintenance. the procedure in the manual is quite helpful. Just remember when you line up the timing marks, it’s possible to be 180 degrees out, so ensure you are coming up on the compression stroke. A simple way to check is just to see if you have valve clearance on both inlet and exhaust when the mark is lined up. Even if the inlet valve clearance is incorrect, the exhaust valve shouled be closed and have clearance. BTW inlet and exhaust valve clearances are not the same on my 420 so I suspect that to be true for the 350. ‘’Download and check the manual, and you will be good to go. I really would suspect fuel and carb first though. It ran ok for quite a while.

 

[bcbuck]

Push right hand brake all the way forward off safety limit switch if bike is set up to start in gear. My 2002 Rubicon runs like that if not off safety.

 

[bcbuck]

Any Luck?

 

[BeCoulter79]

Thanks for the suggestions.
Just got the new one carb on today, started right up and was able to ride it. It is still either backfiring when I let out to shift or slow down, or it something else making the noise, I did read that the timing chain could be loose and slapping or the valves?

rode through all the gears and was fine until I let out of the throttle. Could the carb being not 100% adjusted correctly make it have this issue if in fact it a back fire?

thanks for all the input,
Ben

 

[BeCoulter79]

Another question.
when should the fan for the oil cooler come on? I have not ridden this four wheeler more than 30 minutes so I don’t know if it should have came on yet or if it has been to cool outside.