Carb flooding badly....need suggestions - BuggyMasters.Com - An On Line Mini Buggy Forum and Go Kart Forum

georgia mike · #1 06-01-2013, 11:37 AM

Yerf Dog Spiderbox with complete replacement engine from BMI Karts. No hoses or anything have been changed from the way the unit was shipped to me. It runs fine sometimes with no issues at all. Other times it just floods so badly that gas pours out of the carb throat. Before I figured out what was going on, it had filled the air filter housing to the point that it saturated the filter.

It doesn't do this all the time but today while we were riding it, it was running great then it started to lose a little power and stumble a bit when the throttle was stabbed. I shut it off for a few minutes to take a break, then it wouldn't start again. I pulled the plug and it was soaked with fuel. I put a spark tester on the plug wire to check for fire and it was a-okay, but when the engine spun over loads of fuel shot out. I pulled the air filter inlet tube from the carb and just as I suspected....fuel pouring out again

I've read that the enrichener valve can sometimes cause this. My question is that if it can cause the problem, can I just unhook it and be done with it? I'd much rather worry about a little cold-natured running for a few minutes rather than worry about running the engine without realizing the engine oil has been diluted with fuel after it was parked for a few days.

Miamieddie · #2 06-01-2013, 07:26 PM

Check ur floater.

Masteryota · #3 06-01-2013, 07:34 PM

2nd the float check, also make sure to check the needle and seat for wear and/or trash. Be sure to make notes of the adjustment screws if you go past taking the bowl off, they can be a pain to reset.

georgia mike · #4 06-01-2013, 11:02 PM

That was the first thing I checked. Not sticking, needle and seat look good.

Miamieddie · #5 06-01-2013, 11:09 PM

You sure the floaters not sitting to high? Its the only thing ican think of...

ckau · #6 06-02-2013, 06:52 AM

3'erd on checking that float, needle /seat. Bad enricheners can cause extreme rich conditions but not totally fill or flood the carb. The float /needle/seat is the only mechanism in the system that controls that type of fuel flow.
most likely you've picked up some trash somewhere, deteriorated fuel lines, filter failure, needle tip, the stock plastic tank. The gas we get these days, ethanol? eats the old rubber stuff up.

georgia mike · #7 06-02-2013, 07:17 AM

I'll double check it. The reason I was thinking enrichener valve was that the thing runs great when cold, but got worse after it warmed up, then wouldn't restart after shutting it off. Fuel isn't coming from the bowl vent, it looks like it's coming from inside the carb throat from a passage that looks like the outlet for the enrichener valve.

xlint89 · #8 06-02-2013, 08:41 AM

I too have experienced this on my Spiderbox. Although not so much with the stock carb, but more with my aftermarket carbs I've tried.

http://buggymasters.com/forum/showth...rb+pressurized

I've never been able to figure exactly why this happens, but I've just learned to deal with the issue by installing and using a fuel shut off valve when not in use. It can only dump as much fuel as you'll allow it.

georgia mike · #9 06-02-2013, 09:18 AM

Haha we're on the same page as far as a shut off valve is concerned. I went to the hardware store the other day to try and find something suitable to use, but couldn't find anything that would work without spending more on numerous adapter fittings than I would spend by just buying a regular old fuel pepcock.

I have the carb that came off the old engine, so I may just clean it out and swap it on there to see what happens. It was a brand new replacement installed just before the previous owners roached the final drive bearings by running it with no oil. His logic was that since it was shipped with no oil in there, it didn't need it

xlint89 · #10 06-02-2013, 08:47 PM

You just need an in-line fuel shut off. Most likely for 1/4" I.D. fuel hose.

Prob can find one at a local lawnmower repair shop or on E bay quite easily.

3/16"

http://www.ebay.com/itm/P537-Motion-...afa21c&vxp=mtr

1/4"

http://www.ebay.com/itm/UNIVERSAL-IN...f652a3&vxp=mtr

5/16"

http://www.ebay.com/itm/12-7131-SPI-...2e5d6e&vxp=mtr

3/8"

http://www.ebay.com/itm/Inline-Fuel-...7b5758&vxp=mtr

georgia mike · #11 06-02-2013, 10:00 PM

Thanks for the links. I'm gonna go ahead and order that 3/16" valve and buy some new fuel line while I'm at it. Gonna pull the carb tomorrow and check the float level. Anyone have any measurement specs for float height? Or a link to that general type of maintenance info?

Much appreciated

zman007007 · #12 06-04-2013, 07:08 PM

I dont know if anyone has any measurements for their float level or not, but all I have ever done, including mower type engines, is hold the carb. upside down with the bowl off and make sure the float bottom looks level all the way accross.

georgia mike · #13 06-04-2013, 07:18 PM

Sounds reasonable enough. I haven't had a chance to tear it back apart yet. When I do mess with it I'll take the float and needle out and give it a closer look. I may just need to give the float a small bend downward to help put a little extra pressure on the needle and seat to get a more positive seal. When I had it apart before the float seemed to move very freely, no binding at all, but that was all I checked.