Nothing to do with Silverwings, but still one for you budding mechanics!

I posted this in an offroad buggy forum, but thought one of you chaps might be able to help:

Ok a few weeks ago I posted on here (the buggy forum) for the first time about my crazy idea to form a syndicate with like minded families and buy/build/maintain a buggy for our kids to enjoy. Well that idea went down like the proverbial lead balloon and parents just looked at me whilst nodding in approval yet obviously thinking 'you poor poor disillusioned fool'.

Well not perturbed by my significant lack of mechanical knowledge this poor fool went ahead on his own. Having owned a number of Japanese bikes that just went on and on and on.... I thought as long as the beast has a Japanese motor we'll be completely sorted. So ta da here is our new baby:

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=230446491481&ssPageNam e=STRK:MEWNX:IT

Well all was well in my foolish little world until we picked up this chariot. When we got it home it would start ok but unless you tweaked the throttle she would just splutter and die. Once you were in the machine racing around (great great fun incidentally, but hey no need to tell you guys I guess) everything was good.... but the moment we stopped or came off the throttle she would chug once or twice and then stop.

So as you may have picked up from the Ebay blurb the engine is a Honda GX390. Was my faith misplaced? Surely not since before buying the old girl I did my homework and pretty much ascertained these babies are bullet proof, well as near as. But what goes on below that well crafted surface I have little idea. That said I do remember some things my old physics teacher told me and so I quickly discovered where the carb thingy was (a very proud moment winessed by my wife who previously thought I was a mechanical Philistine). I then took a leap of faith and determined that one of the screw things was in fact the idle thingamajig (the black plastic one seen here Picasa Web Albums - Noddydog - New buggy)
So I adjusted it clockwise a tad and hey presto the engine seemed a lot happier and for a good hour it didn't stall. Just when I thought I surely deserved one of those fake diplomas as a mechanic it started to do the same old thing. Well I knew exactly what to do twist that darn screw a bit more! .... but that wasn't such a good idea and some of you may have guessed what happened next... yes I had a good 'close' look and smell of the grass as my new acquisition dragged me along the ground. Fortunately someone managed to hit the brakes before damage was inflicted to more than my pride.

Hmmm better not turn that screw any more. But aha there's another metal screw just below it, what does that do? I was about to find out when my wife reminded me (as women love to) that I hadn't been too successful with screw No.1 So I left it and still haven't the foggiest idea what it does... I'm kinda hoping one of you chaps will tell me!

OK so what about the spongy thing.. the air filter is it? I remember Mr Boswell (Physics teacher) said that engines don't work well when these sponges are blocked. Another moment of pride erupted inside me when I successfully located this baby (and here it is: Picasa Web Albums - Noddydog - New buggy) Maybe I was back on course for my diploma! Well anyway that all looked like the right colour to me, so I guess I can tick that off!

So at this point there was nothing else to twiddle or explore... so I decided to give up. Those parents were right this poor fool shouldn't have dabbled in this mechanical netherworld.

So what to do next since I can't really let my little one use it as is? Admittedly the engine will run as long as she doesn't idle, so I guess it's not all bad news. But is there anything I can do that won't involve taking it to a real mechanic or being dragged across a field at the mercy of a ghost driver?

Somebody please help this poor fool!

Wing MAN... it sounds like you have a very minor problem of throttle adjustment to me... if it runs with a little fast idle, you should have a cable or adjust link to turn the throttle up just a pinch ... just enough to keep the engine running. One of those screws you adjusted was probably the idle and the other was probably the fuel mixture. It sounds like you have those ok... may have to readjust slightly, but you more than likely need a throttle adjustment. Look for that and get back... some really smart reader is gonna give you more help...

http://www.justanswer.com/questions/1y3qt-i-have-an-older-honda-gx-390-i-replaced-the-governor-rod-and

Good picture in post http://www.justanswer.com/view_image.aspx?href=http%3a%2f%2fww2.justanswer.com/uploads/samthetech/2009-03-28_041828_honda_002.jpg



http://www.honda-engines.com/engines_owners_manuals/ownersmanuals/gx390.htm

Check your serial number ... they may have a

GX Series Carb Check Sheet Poster for your engine
Engine shop manual

They might be the best place to start.


Hopefully the gas has not been sitting there and gummed up the carburetor.

Sadly I think you're right, the gas has been sitting around in the carb/tank. The guy who made it said it had sat in the back of his workshop for 2+ years and he only recently decided to sell it because he needed the space.

I think I'll have to have a mechanic sort it out since I don't have the skills to pull a carb apart.

Thanks for the advice and links though.