Bossdaddy 212 Posted October 29, 2021 The same 2002 Rancher that had the lug nut problem now has another problem. I think it's the carburator, the guy finally got to bring it over for the lug nuts and wanted me to see why it wouldn't take the full throttle. It runs great but when the engine get hot it will not take the the gas past about 1/3 wide open, it just bogs down, loses power. Upon inspection it has what looked to be a new OEM carb on it. I questioned him about the carbs age and he said 3-4 years old but the Rancher was bought for his wife which almost never rode it it just sets in the basement. I told him I would take it off and clean it and look it over. I ordered a rebuild kit just in case. When I opened it up it looked new, I went on and used the rebuild kit, using only the jets and things like that didn't go into the vacuum part of it and put it back on the machine. I got the same results once it got hot. You guys have got me going before so let me hear what I did wrong or what I need to try. Share this post Link to post Share on other sites
Fishfiles 20,147 Posted October 29, 2021 If the diaphragm has a crack , split or hole in it , or not sealing around the edge of the cover , it will do exactly what you describe , bog out when you try to rev it pass about 1/2 throttle ----- 1 Share this post Link to post Share on other sites
shadetree 5,977 Posted October 29, 2021 13 minutes ago, Fishfiles said: If the diaphragm has a crack , split or hole in it , or not sealing around the edge of the cover , it will do exactly what you describe , bog out when you try to rev it pass about 1/2 throttle ----- a new carb, i highly doubt the daiphragm has a crack in it ?, unless the po opened it up maybe ?. i've had this issue a few times. it turned out, the oem snorkel was stopped up with muddobbers nest, was not getting enough air to the carb, but this was on a trx300fw back then. Share this post Link to post Share on other sites
Bossdaddy 212 Posted October 30, 2021 This carb was installed in a Honda shop. The snorkel is clean inside and out, this whole machine is clean, it don't look like it has ever been put in a bad place, the air filter looks new. I have tried this thing with snorkel on and off, with breather on and off, same results. It sounds like it is starving for fuel. Give me more ideas, I will go into the diaphragm tomorrow. One more thing will a carb from a 450 work on this 350? Share this post Link to post Share on other sites
shadetree 5,977 Posted October 30, 2021 1 hour ago, Bossdaddy said: This carb was installed in a Honda shop. The snorkel is clean inside and out, this whole machine is clean, it don't look like it has ever been put in a bad place, the air filter looks new. I have tried this thing with snorkel on and off, with breather on and off, same results. It sounds like it is starving for fuel. Give me more ideas, I will go into the diaphragm tomorrow. One more thing will a carb from a 450 work on this 350? no a 450 carb wont work on a 350.. have ya checked the timing ?. checked valves ?. 1 Share this post Link to post Share on other sites
Bossdaddy 212 Posted October 30, 2021 Have not checked valves or timing. Share this post Link to post Share on other sites
Fishfiles 20,147 Posted October 30, 2021 8 hours ago, Bossdaddy said: Give me more ideas Bad / dirty fuel from a contaminated tank , dirty carb / plug jet , timing issue or stuck or broken valve stem , stretched timing chain or jumped a tooth , weak compression , air boot leak between carb and head , adjustment of valves , diaphragm has a cracked or hole , or the slider /plunger is stuck 2 Share this post Link to post Share on other sites
Fishfiles 20,147 Posted October 30, 2021 9 hours ago, shadetree said: a new carb, i highly doubt the daiphragm has a crack in it ?, unless the po opened it up maybe ?. i've had this issue a few times. it turned out, the oem snorkel was stopped up with muddobbers nest, was not getting enough air to the carb, but this was on a trx300fw back then. I wouldn't consider a 3-4 years old carb new , LOL Share this post Link to post Share on other sites
Goober 1,555 Posted October 30, 2021 (edited) What do you mean “hot?” Warmed up? Change the choke valve. hows the plug look? Sooty? Change the plug. Few miles and hardly ever ridden it’s going to be a dirty carb, dirty plug. How did you clean the carb? Make sure to use pipe cleaners on that enrichment passage. well I assume it ran right when she got it but someone had it for 15 years before she got it. That said, a complete service is in order. Edited October 30, 2021 by Goober Share this post Link to post Share on other sites
Bossdaddy 212 Posted October 30, 2021 I put a new spark plug in it, the one I took out was a little black but not in bad shape, I cleaned the carb with small brushes, carb cleaner and compressed air. Share this post Link to post Share on other sites
Goober 1,555 Posted October 30, 2021 I would change the choke valve. Share this post Link to post Share on other sites
spock 44 Posted October 31, 2021 It's also possible it has a choke cable that's corroded and won't allow the choke valve to close completely. Seen it a few times, something to check out. 1 Share this post Link to post Share on other sites
Goober 1,555 Posted November 1, 2021 Valve? i imagine it could run Ok until it gets warm and then if ya got a sticking valve it could quit on ya. Share this post Link to post Share on other sites
Bossdaddy 212 Posted November 1, 2021 The thing that bothers me and has got me scratching my head is this thing hasn’t got a miss, tick, nothing sounds or acts up at all till about 1/3 throttle then it’s like it starving for fuel, let up on throttle a little and it back to smooth as silk. I changed diaphragm, no change. I think it’s the carb. I guess I’ll go back thru the rebuild again. Share this post Link to post Share on other sites
Goober 1,555 Posted November 1, 2021 (edited) Yeah could still be dirty Edited November 1, 2021 by Goober Share this post Link to post Share on other sites
Fishfiles 20,147 Posted November 1, 2021 The code on side the body of your carb should read VE94A C , it fits 2000- 2003 Share this post Link to post Share on other sites
Bossdaddy 212 Posted November 3, 2021 Changed choke valve, it made no difference in the running. Removed carb again and went back into it , recleaning it and just redoing what I did when rebuilding it. Installed carb and it runs as it should, idles good accepts throttle when called on, I don't know what it was but it's ok for now. I have never seen a ATV as cold natured as this one. It will not take very much throttle until it is completely warmed up even while playing with the choke. Now unlike before when completely warned up it has plenty of power and really run good. Thanks guys for the help, I'm sure I'll be calling on you again. Share this post Link to post Share on other sites
shadetree 5,977 Posted November 3, 2021 3 minutes ago, Bossdaddy said: Changed choke valve, it made no difference in the running. Removed carb again and went back into it , recleaning it and just redoing what I did when rebuilding it. Installed carb and it runs as it should, idles good accepts throttle when called on, I don't know what it was but it's ok for now. I have never seen a ATV as cold natured as this one. It will not take very much throttle until it is completely warmed up even while playing with the choke. Now unlike before when completely warned up it has plenty of power and really run good. Thanks guys for the help, I'm sure I'll be calling on you again. the only thing that stands out to me here, is the top of the carb !. if you do not get the top down right on top of the diaphragm ?, it will have a air leak !. that diaphragm MUST be seated in the groove !. another thing is, ARE YOU 100% SURE YOU HAVE TO CORRECT CARB AND CARB SHINDY KIT FOR THAT YEAR MODEL ?. i ask this, because i know for a 100% fact, i can let this '91 trx300fw sit all day, all night, go out, turn the choke on, hit the start button, and it fires off right off the bat..within a nano second !. Share this post Link to post Share on other sites
shadetree 5,977 Posted November 3, 2021 word from the wise, time after time, i have done something on projects that i work on, all goes well while working on something, then later on, it wont work like it was BEFORE i started tearing into it ?, ok..i stand back..and think..what did i do different than before ?, what changed ?, what did i do different than before ?..then sure as rice is white ?!..it stands out to me..and i see what i did different !. moral of this post: if it takes 100 times to take a carb apart ?( or whatever you are working on ? ), do it over an over..the problem will shine like a turd in a punch bowl to you !. Share this post Link to post Share on other sites
Bossdaddy 212 Posted November 3, 2021 shadetree, thanks for the input. There has never been a problem at all about it starting, it starts and idled great and still does. The whole problem was it wouldn't take the gas when called on, now it does it's just got to be warmed up good to perform as it should. I verified the rebuild kit as being correct. 1 Share this post Link to post Share on other sites