Quad carb problems???

[hazzygawa]

I have problems with my little quad bike. It is only a toy but really handy to go across the fields in when I work for the farmers around me.

 

It starts fine, idles ok but when you put the throttle under load it just dies. It started doing this the other day, so I had to push it back to my truck. Sweat and anger!

Does it sound like it's running rich?

 

I only really know diesel engines so can anyone help and give me a few pointers.

 

Thanks

H

[Rich2484]

Air leak in carb.

 

If its four stroke. Could be the fuel bowl not allowing enough fuel through. (Doubt this tho as its ticking over)

 

First a few questions from me.

 

Does it smoke. Does it tick over all day no problems. Does it backfire at all. What colour is the plug. I need some more info. Also make model and engine size please.

[hazzygawa]

It's 2 stroke

Yes it does smoke

I think it will tick over all day

No back firing

 

I will find out what make it is. It is some Chinese /jap strange model/make

 

Not sure about spark plug- will check when I get a mo.

 

Thanks for your help

[Andy Collins]

I think it may be a blocked main jet, does it have an inline fuel filter, if so change/clean it. But Rich is more savvy mechanic than I am, so go with his diagnosis first. I just start with simple stuff like spark plug, fuel filters, air filters and then throw the damn thing in the corner when it still doesn't work!!

[Rich2484]

Don't be too quick there Andy.

 

I would check the plug first and it will give a good diagnosis about what's happening in the cylinder. If its firing fine then the plug will be a nice colour.

 

Now we know its two stroke go for the obvious on a two stroke. Is the carb allowing air into it through any sort of air line.

 

Have you had the carb off and cleaned it out yet. Best thing to do is think of it like a saw. If your saw wouldn't rev up what's the first thing you would do? Other than throw it in the corner and wait for e scrap man.

[muttley9050]

Sounds to me like blocked main jet, running on pilot jet until you give it some revs. My advice would be, remove and open carb, use a paint brush and petrol to clean everything. Locate the main jet. Probably brass and it will unscrew. Remove carefully and use some thin copper wire to poke any gunk out of jet. Flush through with petrol and a short blow like a straw. Rebuild carb and replace. Then test....

Hope this helps

[Andy Collins]

I hate poking things with wire, especially jets, a stiff nylon bristle will clear most jets ok, or a blast of compressed air, though I have blasted the fiddly jet across the floor with a compressor!!! Hours of fun searching for it then ensued I hate mechanicing!!!

[hazzygawa]

I can always rely Andy to add some humour to a very frustrating topic