FZR 400 3tj1 Strange carburetor problem

[Pab10]

Hi everybody, this is my first post...


I recently buy a fzr, it have carburetor problems , it's a 3tj but have a 1wg engine fit on it ... It turn on easily at morning, accelerate properly when i turn the throttle . But when i take it for ride, everything is good when you go over 10 000rpms, but if i go lower than that mixture go overrich, and it begin hesitating and loosing power till it turn off... And if i decide turn it on again, i can't because there are fuel excess on cylinders...

So, i decide to take apart the carbs to make some cleaning.. They were pretty dirty, i clean them up, and put new every o-rings and needle valve, when they were ready, i install them on then bike and set the float levels and pilot screws... I turn on the bike, everything was allright, but when i take for a ride it began with the same problem... At this moment i don't know what i can do... Temporarily i install a switch on the fuel pump, so i turn it off before mixture get overrich, haha....
*Something interesting that i forgot, is that lowest idle i can go is 2000rpm, if i go lower that, bike turn off....


Any help will be appreciated, because that switch became a headache hahaha.... Thanks!


Sorry about my english...

[Pab10]

This is my poor little fzr...

[rockTJ]

Firstly, nice bike

All 3TJ have engine number 1WG so dont worry about that.

How old is the air filter. It's unique to the 3TJ so tends not to get changed....

These bikes have a problem with emulsion tube and needle wear at high mileages??? How many km's on your clocks???

Have you made sure the choke mechanism isn't jammed on at the carb end?

No misfiring - clean spark plugs?? Exup valve working as it should?

No cracks in carb rubbers??

Chris

[Evilchicken0]

Try changing the fuel filter

[Hogdigerdy Dog]

looks like a nice machine
mostly what rocktj said
but also have you checked that the fuel pump and exup are working properly
when you turn on the ignition, before you hit the start button, you should hear a wir wir sound, that's the exup valve zeroing itself (basically opening and closing)
also you should here a kind of pump pump bubble sound, that's the fuel pump priming itself which should stop after a few seconds (the float bowl are pressurised only about 2 psi but it's enough) if yours keeps going then it could be the pump is not working correctly and this would explain why it works at high revs as your using all the fuel but at lower revs it just floods

[Pab10]

Thanks for quick reply!!

Thanks Chris it's a bit incomplete but i'm working on it...

Yeah, i think that too, but that engine doesn't have the threads on the head to screw on the frame, instead of that it have holes on each side on bottom for a bracket (like 1wg, 2tk & 3en's)... Actually i think its a 3en engine, because carburetors and cdi have stamped "3en-10" and many electric parts are from a 3en, but, how i will know if it's from 3en1 or 3en2..?
Here is a picture from the engine:


-It have installed 3en airbox and the air filter is close to new...

-Clocks have 31 767km, but don't know about the engine... i have these pictures of emulsion tubes after i take apart the carbs... Now i pay attention and i realized that 3 of those doesn't look soo good at all... what do you think about them.?



-I check again the choke and every lever slices easily...

This is how the sparkplugs looks like:


-Yep the exup works properly, actually the servo wasn't installed, but i allready install it... incredible performace upgrade ...

-I can't see clearly the rubber because the carbs are installed, it looks like them have some cracks on top where the clamp goes, and have some RTV in different parts .......


Something interesting that i forgot, is that lowest idle i can go is 2000rpm, if i go lower that, bike turn off.... and it suppose be 1250- 1350, right.?



Thanks!!!

[Pab10]

Try changing the fuel filter

i'm going to tried... But here where i live there are no parts for fzr, i think a universal filter will work till the right one arrive...?

Thanks!

[Pab10]

looks like a nice machine
mostly what rocktj said
but also have you checked that the fuel pump and exup are working properly
when you turn on the ignition, before you hit the start button, you should hear a wir wir sound, that's the exup valve zeroing itself (basically opening and closing)
also you should here a kind of pump pump bubble sound, that's the fuel pump priming itself which should stop after a few seconds (the float bowl are pressurised only about 2 psi but it's enough) if yours keeps going then it could be the pump is not working correctly and this would explain why it works at high revs as your using all the fuel but at lower revs it just floods

Thanks man!

Yep, exup is working properly... Fuel pump is new, i buy it from ebay (http://www.ebay.com/itm/FUEL-PUMP-FZR60 ... 21&vxp=mtr), i also buy after that an original used pump, either looks to work properly, 5 seconds before i hit the start button... But i don't have pressure gauge to measure it, going to see i if borrow one from a friend..

[Maelstrom]

Pab10
Is there a time when you did not have this problem?
If so, what changed between not having and then having the problem.
Are all 4 cylinders showing signs of being too rich?

[Pab10]

Pab10
Is there a time when you did not have this problem?
If so, what changed between not having and then having the problem.
Are all 4 cylinders showing signs of being too rich?

Nop, since i bought it had the same problem...

Checking sparkplugs look like cylinder 1 is richer than others, and actually when i try to turn it on after is flood sometimes she turn on but just cylinder 1 doesn't work, i mean cylinder 1 continue flood...

Thanks!