Carburetor problems?

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Carburetor problems?

Postby zelitz » 05 Sun Jul, 2009 9:50 pm

Hey guys I posted this on the Aircoolers.org site as well.
http://aircoolers.org/v/showthread.php?t=9766

I am by no means an expert and pretty new to air cooled engines in general. My buggy is running like pshaw and has a very inconsistent idle. Here is what happened and what we checked. If you guys have any advice or suggestions I'm all ears.

So two weeks ago I took my buggy to the beach. I got sand everywhere, but washed it a few times. And the only thing the I noticed was the throttle sticking between the beach and the wash. Otherwise nothing felt or sounded weird at all. I ran it to the store last week and it ran fine, no problems.

Yesterday I fired it up to take it to my sisters house (about an hour each way) and noticed it wanted to just keep dieing at a stop. I didn't think much of it and just turned the idle up and everything seemed fine. After about 30 minutes I noticed the throttle felt really odd. When I would slow down to about 35 in second it felt like the throttle was surging. After a few more stops and starts I noticed it was just running like pshaw. I turned the idle up, but it was still choppy. It has a cam in it, but I have become pretty tuned into that sound and this was completely different. At without touching the throttle the idle was very inconsistent.

Last night I had it idling letting my father share his thoughts. Hes been working on cars since he was a teenager and immediately said it sounded like there is something wrong with the carbs. Well I left it idling and he gave it a push so it would roll backwards down my sister's driveway. As the rear end became lower, the engine rev'ed up to about 30% throttle without me touching anything, and then back to idle when we were on level ground.

Today we decided to take a look at it. We immediately noticed it was running pretty rich and would blow smoke if you got on the throttle. We pulled the spark plugs thinking maybe one was dead, but 2-4 were great, 1 was pretty black. We swapped plug 1 for 3, and there was no change in the idle. We pulled both of the spark plug cables individually and for both the engine instantly had a noticeable difference. So with the air filters off we looked with a mirror and saw the carburetors dripping fuel at idle. From what my dad tells me thats not so great. I have a pretty basic understanding of how the carburetors work and i'm thinking it sounds like a problem with my float. I cant think of anything else that would change the idle speed that drastically depending on the incline of the vehicle.

I bought the buggy a year ago and this is the description for the engine

Engine/Transmission
Rebuilt 1776cc (69mm x 90.5mm) with 200 miles
Ported/Polished stock heads with new valves and solid rocker shafts
Color matched Scat fanshroud with C.B. Performance Aluminum fan/coil plates
Engle 110 camshaft
Bosch 009 Distributer w/ Bosch Blue Coil
30mm Full flow oil pump w/ external filter
Dual 40mm Kadron Carburetors rebuilt by A.J. Simms
Tri-mil ceramic coated exhaust
Rebuilt swingaxle transmission

I've only put about 2000 miles on it since I bought it, but 700 of that was towing between corpus and san antonio a few times. We changed the oil at 500 miles. At 1800 miles we set the valves and changed the oil again. No oil leaks and it was running great two weeks ago.

Right now it runs rich, but like a dog. I think my sand days are over, but I'd really like to figure out whats wrong.

Thanks in advance,
Kenneth
zelitz
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Postby seabeebuggy » 05 Sun Jul, 2009 10:08 pm

Yes it sounds like the float is stuck. Check it , clean out the carb. Make sure the float levels a good, adjust the tabs if needed. Make sure idle jets dont have sand in them.
Please note I do not know a thing about Kads. I do know a lot about webers.
Have buggy , Looking for a good time.
seabeebuggy
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Location: Clovis NM

Postby zelitz » 05 Sun Jul, 2009 10:14 pm

seabeebuggy wrote:Please note I do not know a thing about Kads. I do know a lot about webers.
Haha, yeah I'm hearing a lot of this lately. :D
zelitz
Buggy Builder
 
Posts: 12
Joined: 30 Tue Jun, 2009 1:02 pm
Location: Texas

Postby jspbtown » 06 Mon Jul, 2009 8:40 am

Check out the AJSims website. It has everything you need to know about Kads.

My opinion is you have a linkage problem.
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Postby Fscott » 27 Mon Jul, 2009 3:09 pm

Too much fuel pressure. Should be around 1.5 # and no more than 2.0 with it running. This is for Kadrons. The other could be missong check balls for your squirters.

Good luck
Frank Scott
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