SU Carb Problems!!

[Mudhog]

Went to start Mudhog and fuel was just pissing out the over flow pipe all over the ground

Pulled the problem carb of and cleaned it and refitted it. Tried to start it again with the same result.

What else can I do or check?

I need help

Cheers Brett

[bryan.daley]

Does the float float? Dirty or worn needle valve.

[SP450andLE]

Yeah, pull the float chamber off and make sure it is all working properly, and nothing is blocked. May be a good time to take the whole carb apart and clean it up?

That's what I've been doing with the ones from my Mini, I reckon it would be worth it

[chrome]

have a nose thru this


http://www.them-g-c.com/index_files/Page2858.htm

[SP450andLE]

Also, can we get a photo of where it is leaking from? I may refer to my stripped down one then to figure out exactly why it's leaking

[Sadam_Husain]

Does the float float? Dirty or worn needle valve.

yep if its pissing out fuel thats where you want to be looking, the float and needle valve control the flow of fuel into the carb and if the needle valve isnt closing the fuel isnt going to stop flowing into the carb

[Mudhog]

Thanks everyone for the help.

I'm going to soak the float in meths over night to check that it doesn't have a hole in it. I'll clean all the carby parts again ready for the carb specialist in the morning and see what he have to say.

I've spoken to a couple of guy's and the general feeling is that the needle is not seating properly any more or the float is jaming or damaged.

Here's hoping so!!

Cheers Brett

[Mudhog]

have a nose thru this


http://www.them-g-c.com/index_files/Page2858.htm

Thanks

Very helpful

[Mudhog]

I woke up around 2am and couldn't sleep after my 3 1/2yr daughter had said to me just before she went to sleep that she was very worried about Mudhog not working for this weekend So I pulled the carb apart and started to clean it.

I found a fresh score mark on the side of the dash pot, it looks like something has been jamed between the housing and the dash pot.

I cleaned all the grime of all the other bits and checked the float, it looks fine.

I can now remember the dash pot cap coming lose at Woodhill on the last trip

Maybe abit of that lovely Woodhill Sandy grit got in there

So the question now is, do I go and see the carby guy's first thing or do I try it and see if this has fixed it?



Once I re-assembled it the dash pot now sat down hard with no problems.

[Pedro]

I woke up around 2am and couldn't sleep after my 3 1/2yr daughter had said to me just before she went to sleep that she was very worried about Mudhog not working for this weekend So I pulled the carb apart and started to clean it.

I found a fresh score mark on the side of the dash pot, it looks like something has been jamed between the housing and the dash pot.

I cleaned all the grime of all the other bits and checked the float, it looks fine.

I can now remember the dash pot cap coming lose at Woodhill on the last trip

Maybe abit of that lovely Woodhill Sandy grit got in there

So the question now is, do I go and see the carby guy's first thing or do I try it and see if this has fixed it?





Once I re-assembled it the dash pot now sat down hard with no problems.

dash pot controls fuel mixture into the engine, the needle valve driven by the float controls the fuel flow, if you turn the carb upside down and blow thru the fuel inlet pipe, you should not be able to blow thru it, then if you turn it up the right way you should then be able to blow thru it, if you can blow thru while the carbi s upside down the valve is not seating properly or is stuffed, check float hieght as well,

Pedro

[bryan.daley]

I woke up around 2am and couldn't sleep after my 3 1/2yr daughter had said to me just before she went to sleep that she was very worried about Mudhog not working for this weekend So I pulled the carb apart and started to clean it.

I found a fresh score mark on the side of the dash pot, it looks like something has been jamed between the housing and the dash pot.

I cleaned all the grime of all the other bits and checked the float, it looks fine.

I can now remember the dash pot cap coming lose at Woodhill on the last trip

Maybe abit of that lovely Woodhill Sandy grit got in there

So the question now is, do I go and see the carby guy's first thing or do I try it and see if this has fixed it?



Once I re-assembled it the dash pot now sat down hard with no problems.

Needle valve and float is the area for flooding problems. Check the state of valve - use carb cleaner through it all, check condition of valve as it may be worn.
Also think about checking the fuel filter, ie is there one and if there is replace it as this is where dirt can get through.

Not 100% sure but I thought you need air through the carb to have fuel sucked out the jet, so a stuck pot may be from the last take down? ie not the problem.

[Mudhog]

Just done the blow test and yes I can blow it both ways

I'm off to the carb guy's to see if they can fix it

Thanks for the help

Cheers Brett

[SP450andLE]

Hey, did you manage to sort the problem out?