[hammy53]

Guy's and Gal's I need help! I have a 02 TRX500. It had been sitting for 2-3 years. When I tried to start it, no luck just cranked(with a new battery) When I primed it thru the carb it would run that gas out and die. I went ahead and ordered a new carb. While I was waiting for the carb to be delivered I found the inlet clogged with junk. I cleaned the inlet out made sure the needle and seat was working properly and reinstalled the old carb. It started and idled perfectly. When you throttled it would bog down until you released the throttle, then it would return to a good idle. When I would put it in gear it would just jump a few times and die. Installed new carb... same thing happens. I am on a very limited income and can't just take it to the shop. So I took my limited income and bought a CDI, same thing.

PLease any suggestions? note: It will start in safe mode but then jumps a few times and dies. It won't move a foot.

 

[ktriebol]

Sounds like an air leak in the area between the carb and the cylinder head. Make sure the carb is fully seated.

 

[Jeepwm69]

Welcome to the board. I would take the original carb apart, clean it, and try it again. I'm guessing the "new" carb is a chinese replacement, not an OEM Honda carb?

What about the CDI? Is it an OEM part? If not, put the original back on.

 

[Nanook12]

Make sure your fuel system is clean, from the tank on down. Blow out/purge the whole system. Make sure you have a good flow of clean fuel. Do what was previously suggested. I would go through the original carb and make sure all the gunk is blown out. Set the float to specs and if you have clean fuel and a good flow you should be able to run. If it won’t manage a sustained run, you may still have a weak source of ignition. Don’t keep spending your limited income on parts chasing! You can flow check a carb on the bench, check YouTube.

 

[hammy53]

I did as suggested and it starts and idles very well. I set the air mixture screw to 2 5/8 turns as stated in manual but I am having a hard time adjusting it. It doesn't want to throttle up it bogs down. I don't have much hair left. I had to walk away last night. I wish I could upload an attachment. Is there anyway I can add an attachment some where were you could see it running?

 

[Goober]

You took the original carb totally apart and used a rebuild kit?

Did you put the OEM CDI back in?

It sounds like fuel starvation to me

 

[hammy53]

No I didn't put a rebuild kit in it. I'll order one in the morning. Any certain brand? I want to get it right now. It is the original and I put the original CDI back in it. It's not funny but when you try to cut corners to save money it usually costs you more. Let me know what kit so I can get this right. Thanks

 

[Goober]

You bet. I use Shindy kits most often, altho mine are older (86-93).

Read up on the carb ‘sticky’

I don’t know how your carb works, On mine i crank the throttle the piston pulls up to bring fuel up into the carb throat. If your jets are clogged the air/fuel mix won’t be right. Also if you have a vacuum piston the old fuel sticks it in place so you get very little throttle response.

Very carefully read the service manual about cleaning and inspection

I have posted plenty of pics about how to clean carbs, too. I use berryman chemtool, dental brushes, cotton swab, pipe cleaners, etc. don’t get any cleaner on rubber parts it will melt plastic

 

[hammy53]

Ok, first I pulled the original carb down and sprayed the crap out of it, Didn't put a kit in it yet, re-installd it. It starts and runs great until I put it in gear. It dies like it's out of fuel then starts right back up. I then started it in safe mode and was able to get it back to my shop. Could the throttle positioning sensor cause this?

 

[retro]

After sitting for years with rotting fuel in it, the carb will require a lot more work to clear it than spraying it down. It probably does not need any major parts, but will require a very thorough multi-day cleaning session. Berrymans Chem-dip in the 3 quart can might help. Disassemble the carb body completely (except for the throttle plate & shaft), all jets, rubber and plastic parts, etc. must be removed from the casting. Then submerge the castings and other metal parts in the Berrymans for a couple days, turning/stirring them at least twice to insure that the solvent reaches every tiny passage.

After a couple days in the soak, remove the parts and blow compressed air through every passage, in all directions, where its possible to reach with your air nozzle. You can dip the carb casting a few times while you are blowing it out to help flush out the loosened, softened junk. Rinse well with water when you're done and blow through everything again until its dry. Then, using a spray can of Berrymans, squirt solvent through every passage using the supplied red tube attached to the spray head to verify that solvent flows out through every passage and no plugging remains.

Sometimes ya gotta use pipe cleaners, tiny brushes etc., as @Goober suggests, to get all of the junk out that is jamming up the passages. Search for his carb threads... you'll find lotsa great instruction and lotsa great pics.

Bottom line: Cleaning carbs is tedious, demanding, time-consuming work. It takes a lot of effort (& luck) to be successful 100% of the time. Do your best, be patient, be thorough, and you'll win 99% of the time on your 1st attempt. Some carbs will require several attempts though... so don't be discouraged when that happens... just do it again... work smarter, work harder.

The best advice you'll ever get concerning carbs is:
Read, understand, follow the service manual disassembly, reassembly and setup steps word-for-word all of the way out to the last instructive paragraph. Make sure you get all of the tiny rubber parts back in there, and back in the proper order too. The manual is your best friend... if you need new rubber parts a genuine Shindy kit (or OEM) can be purchased.

Let us know if we can help you.

 

[LedFTed]

its been sitting a long time. it will require patience, to get in back where it was. if it ran on ethanol gas, even more. some sprays may damage rubber gaskets. read through the carb sticky.
dont buy china carbs. ya may also want to make sure the fuel tank, is not compromised, as in soot, an other debree. might be a fuel filter in the tank. stuff like that.

 

[hammy53]

Well, lets get caught up! I started fresh, I pulled the tank and cleaned it. Replaced the fuel line. So I knew I was good to the carb. During this time I had pulled the carb all the way down and put it in the carb cleaner basket and let it soak for 24 hrs. I pulled it out sprayed it down turned it over and put it back in the basket and soaked it another 24hrs. Pulled it out sprayed it down real good with water then air. cleaned out all the holes! Took all the brass sprayed it down with water then air. I took some liquid wrench and sprayed all the orifices.

Reinstalled the carb on the engine hooked it all back up...……… guess what? NO GAS! I mean every gas can was empty! Had to drive 15 miles to the nearest station and bought 5 gal of gas came back to the shop gassed it up, hit the button and it started and ran better than I've ever see it run!

Guys I am so happy right now! I could spit nickels!LOL:big-grin Thank you for being so patient.

 

[retro]

Thanks for sharing your success story!!! Great work!

 

[hammy53]

Retro, thanks for all the help! Now I have a different problem. It starts and idles good and it takes acceleration well too. However when I put it in gear it dies. Sometimes I'll get ten feet sometimes none. I let it run for about 3-4 minutes before I took it out. I took the tank off washed it out cleaned the pickup tube, made sure I had good fuel flow to the carb. Could this be an air/mixture screw adjustment?

 

[retro]

Sure, see if you can fine tune that idle mixture after the motor reaches full operating temperature. Then adjust the idle speed to 1450-1500 RPMs.

Make sure that you adjusted all cables right when you reinstalled the carb. The choke valve should have about 1/8" cable freeplay closed.

Also warm the motor up good before driving the bike, especially in cold weather. I warm mine up for 10 minutes before riding it during the summer months. Ya gotta let the piston get hot and the motor oil beginning to get warm before leaving.

If the bike does not sputter when its hot, but does when it is cold, you'll know why...

Before you run off and forget you should adjust the valves. Folks rarely maintain them, which leads to valvetrains wearing out prematurely.

Hollar if there are any more problems.

 

[Goober]

Did you replace the starter (choke) valve? Might be rich.

How’s the plug look? Really sooty? Clean it with carb cleaner and brass wire brush.

Is the new CDI you bought an OEM for the exact model you have? (So many models of 02 TRX500 i don’t know how many CDI variants there might be).

Throttle position sensor—does this thing have one?

 

[hammy53]

I think I've covered most those bases, EXCEPT the throttle position sensor. It starts and idles great throttles up great but when I put it in gear 9 out of 10 times it shuts down. I did have the TPS off the carb but I don't know if it's set right. Could this cause it to die like this? Sometimes I might get 10 feet but that's it!

 

[LedFTed]

out of curiosity, did it have a gas filter in the tank, not that i think a problem lies there?.. at the moment, i'm going with idle,, ,, i dont expect to be correct. there is a lot more that goes to adjusting a carb, then just the carb..

 

[hammy53]

I'm sorry but I'm getting confused about adjusting the TPS. I did have it off. Could I get some help with this?

 

[Jeepwm69]

If you look in the factory service manual it gives you instructions on setting up the TPS. You have a copy of that manual downloaded?

https://www.hondaatvforums.net/foru...nual-help/50817-service-manual-downloads.html