how to clean carb

[vindell]

have a eton 70cc viper 2-stroke, dealer told me i needed the carb circuoy cleaned. yhey want 160.00 for doing this. is this something i can do myself

[byromh]

I would like to know this all so.

[Dylan189]

Go to the auto parts store get some carb cleaner, take off the carb and spray it. The stuff is like gas wont hurt it a bit just follow the directions on the can.

[rapple]

You should remove the carb and take it apart to clean it. Grab a parts diagram from bikebandit or somewhere so you can see how it's assembled. Soak the jets for an hour or two in carb cleaner and clean all of the passages. I use a piece of coax cable with the outside stripped to clean out everything. The copper wire is soft enough that you shouldn't scratch anything if you're gentle. A stiff nylon bristle from a brush would be even safer.

Once everything is clean, check the gaskets and o-rings and replace if they're worn. Reassemble and ride.

[joker11]

Spraying carb cleaner in your carb will not work for anything other than regular grime during use.

If your carb is clogged like mine was from sitting all summer and the gas varnishing up, you will need to completely disassemble the carb. Let me tell you, it was easy. There is not a lot going on in there.
I bought the gallon jug of carb cleaner. You just put the parts in there and soak for a couple hours. They come out looking brand new. You may have to brush some spots, but I didn't.
I used a torch cleaning kit, the kind for oxy/acetylene torches, to clean out the jets. It was a world of difference.
Put it back together and BANG, it fired up on the first crank and idled like it was still on the showroom floor. My TRX250EX is almost like new again. I am so happy.

The carb cleaner spray is not going to get into areas that are dried and gummed up. In my carb it was the float valve that was actually stuck and would not move, so I wasn't getting any gas.

good luck!

[xjoedirt55x]

Once you tear the carb down and clean it, is there any sort of adjusting you will need to do once you put it all back together?

Thanks

[rapple]

You'll need to adjust the idle speed and idle mixture.

Start with the idle speed screw lightly seated, then back it out 2 1/4 turns.

Warm up the engine and set the idle speed to 1400 RPM.

Then adjust the idle mixture screw in and out a bit until you find the highest idle.

Re-adjust the idle speed back to 1400.

Blip the throttle 2-3 times, and re-adjust the idle speed again if necessary.

Turn the idle screw in just a bit and re-check the idle speed again.

[Rockguy]

Originally posted by rapple
You should remove the carb and take it apart to clean it. Grab a parts diagram from bikebandit or somewhere so you can see how it's assembled. Soak the jets for an hour or two in carb cleaner and clean all of the passages. I use a piece of coax cable with the outside stripped to clean out everything. The copper wire is soft enough that you shouldn't scratch anything if you're gentle. A stiff nylon bristle from a brush would be even safer.

Once everything is clean, check the gaskets and o-rings and replace if they're worn. Reassemble and ride.

I have a rebuild kit. I'm looking at the bike bandit site. Is there anywhere I can get a look at a 300ex specific manual? I don't want to mess this up

[rapple]

The Honda shop manual is pretty useless in that regard. Your best bet is to print out the diagram from BikeBandit and if you have a digital camera, take some pictures as you disassemble things.

It's pretty easy, if you're nervous, you can swap the jets one at a time, but if I recall, they only fit one way, so there's little chance of messing things up.

One pitfall to keep in mind is to avoid getting carb cleaner on any of the rubber gaskets. It'll swell them up and ruin them.

The only other thing is to work someplace where you have good lighting and a clean surface so you don't lose any of the little parts.

Other than that, it's a breeze.

[Rockguy]

Thanks rapple. I have most of it figured out. I'm stuck on how to get that long needle jet out. The one that goes through the throttle body. It's part 2 in the schematic. Do I have to take all of that arm set stuff out. Parts 8 and 12. They look like a pain to take out. No screws. Looks like they slide in. Not sure how hard that would be. That seems to be my biggest obstacle right now.

I do have a digital cam and, I have taken some pics. I got the kit from Honda but, it's identical to this one

http://cgi.ebay.com/ebaymotors/HONDA-TRX300EX-300EX-CARB%2FCARBURETOR-REBUILD-KIT_W0QQitemZ140362775611QQcmdZViewItemQQimsxZ2009 1126?IMSfp=TL091126201004r1834

[rapple]

I went back and looked again at the manual... It's actually quite a bit better than I remembered.

You remove the top cover of the carb and you'll see a set-screw on the little arm. Remove that and the washer and the shaft should slide out allowing the arm to come out.

There are 2 more screws that attach the needle jet to the throttle slide.

Take care not to strip those... Some PB-Blaster/WD-40 and a good screwdriver will help. Once those screws come out you should be able to remove the needle valve. The clip should be on the 3rd groove from the bottom.

One other thing to be extra careful about is removing the pin that holds the float in place. The little tabs that the pin slides into can be a little fragile. Tap gently to remove the pin. The tabs have been known to break and if that happens, the carb is trash. I've removed lots of these on several carbs and never had a problem, but a light touch is called for.

[Rockguy]

Thanks rapple. I have already taken the float out. The pin came out with no problem. I took an awl and was thinking I'd have to tap it with a hammer but, when I pull the awl against the pin it slid right out.

I had already taken the top off the carb and took that screw and washer out off. At that point it seemed like I could only slide the shaft a little bit. I wasn't trying all that hard because I wasn't sure I was doing the right thing. Maybe I can compress that spring a little and get it out like you say. If that's what the book says to do then I should be able to get it.

[Rockguy]

Originally posted by rapple
I went back and looked again at the manual... It's actually quite a bit better than I remembered.

You remove the top cover of the carb and you'll see a set-screw on the little arm. Remove that and the washer and the shaft should slide out allowing the arm to come out.

There are 2 more screws that attach the needle jet to the throttle slide.

Take care not to strip those... Some PB-Blaster/WD-40 and a good screwdriver will help. Once those screws come out you should be able to remove the needle valve. The clip should be on the 3rd groove from the bottom.

One other thing to be extra careful about is removing the pin that holds the float in place. The little tabs that the pin slides into can be a little fragile. Tap gently to remove the pin. The tabs have been known to break and if that happens, the carb is trash. I've removed lots of these on several carbs and never had a problem, but a light touch is called for.

It's not coming out. The only way I can see is by somehow taking all that throttle linkage off. I hate to be doing that if it's unnecessary. At this point, I just don't see another way. I can't seem to find the service manual online. This is getting frustrating.

[Rockguy]

Originally posted by rapple




There are 2 more screws that attach the needle jet to the throttle slide.

Take care not to strip those... Some PB-Blaster/WD-40 and a good screwdriver will help. Once those screws come out you should be able to remove the needle valve. The clip should be on the 3rd groove from the bottom.



I finally got the arm out. I simply detached the spring from the shaft and then, I was able to pull it out far enough to get the arm out.

I'm now stuck on those two screws attaching the needle jet to the throttle slide. I'm soaking them in WD40 and I have a good #1 and #2 Phillips screwdrivers and, can't get it to break loose. The screwdriver wants to slip. I don't know if anyone knows any tricks. You can't get down in there to use vise grips or anything and, I don't want to damage the slide

[rapple]

I haven't removed mine, but WD40 and patience are probably your best options.

Inspect the needle carefully, if it's not worn or damaged, you don't necessarily need to replace it.

[Rockguy]

It doesn't look worn or damaged but, since that passageway runs from bottom to top, I'd really like to get it changed if possible. I'm doing all of this because of the symptoms in this thread I started awhile back.

http://www.exriders.com/vbb/showthread.php?s=&postid=3759952#post3759952

[Rockguy]

I've rebuilt the carb and it now keeps running. The only problem remaining now is that I can't control the idle. It revs up pretty high without touching the throttle at all. The idle screw has no affect on it. I'm baffled. I took a look in the linkage area to make sure I didn't have something messed up and it all looks good.

[dvx400_boy]

well your first problem was buying an eton hahaha

[dvx400_boy]

and your second problem is if you try to open the carb to clean it you will most likely get poisoning from lead hahahaha

[rapple]

You may have put the throttle slide in the wrong way. There's a slot in it... unscrew the throttle cable and spin the slide around 180 degrees.

[Rockguy]

Originally posted by rapple
You may have put the throttle slide in the wrong way. There's a slot in it... unscrew the throttle cable and spin the slide around 180 degrees.

Thanks rapple. I will check that out.

[Rockguy]

The only thing I can see that doesn't look right is that the idle screw where it enters the carb cannot reach the stop that it looks like it's supposed to rest on however, you can't make it reach it. The throttle cable is only so long. I have taken pictures and made a video of me pressing the throttle. Perhaps someone can see something amiss. I drew a red arrow to the one part that looks like it should rest on the throttle screw adjuster and a blue arrow toward the throttle adjuster itself. I'm scratching my head on this one.

http://i82.photobucket.com/albums/j262/Rocguy/4%20wheeler/th_4wheelerthrottleshort.jpg (http://s82.photobucket.com/albums/j262/Rocguy/4%20wheeler/?action=view&current=4wheelerthrottleshort.flv)

http://i82.photobucket.com/albums/j262/Rocguy/4%20wheeler/th_throttlesideofcarb2Edited.jpg (http://s82.photobucket.com/albums/j262/Rocguy/4%20wheeler/?action=view&current=throttlesideofcarb2Edited.jpg)

[Rockguy]

Update

My brother and I were messing around with it. We took the cable out of the little slot it slides into and were just playing around. We put it back and it goes down there now. Perhaps it was as you said rapple about having it in wrong even though it looks like the cable goes right in the middle of that slide thereby making no difference.

I'm really not sure what we did. It's finally running right again. Thanks for all your help

[rapple]

Wasn't me :-) I was actually thinking about an entirely different type of carb that has the throttle cable attached to the needle... those have a slotted slide that's easy to put in backwards.

Glad to hear that it's working... sometimes a few hours tinkering is all it takes.