new FJ owner carb questions

[holes41]

first time post , been reading a lot here for almost 2 months before I bought my FJ. After owning an 89 FJ1200 for 3 weeks and loving every minute of it, I have ran into a carb issue that scared me to death while riding today. I was sitting at a red light and noticed my idle slowly dropping and the bike started to stumble. I gave it a quick blip and it revved to 6k and slowly went back to a normal idle and then started to load up again. I rode it home (runs fine above 1500rpm) and fuel was dripping from one of the overflow lines and after 10 minutes I tried to start it and it seems hydrolocked and now my oil level has risen by quite a bit, ok so there is fuel in my oil now, and it's off to a great bike mechanic I know. Could it be a stuck needle valve or float problem, fuel pump? Is this a known issue with these bikes? The bike did this once a week ago but it stopped when I fixed a broken T fitting coming off the front of the fuel tank and tapping the float bowls, I don't know if the T fitting caused the initial overflow or if tapping of the bowls stopped it the first time. thanks for any advice.

[FJmonkey]

Sounds just like you have one or more needles with some crap keeping it from closing fully. It happens on carb equipped bikes. The last time I saw this we fixed it by draining the offending bowl, and when it filled back up it flushed the crap out. You can also try tapping on the carbs to get the floats to giggle and possibly dislodge the crap. Others reported a gentle ride off a curb to jostle the fuel around to the same effect.

[movenon]

Welcome !  Yes it sounds like you need to remove the bowls and clean the needle and seats or replace them.  There is also an O ring that go's around the needle and seat valves that probably should be replaced.  Sounds like you need to dump the oil and change the filter from your description.  

With out going into a lengthy "how to" how do you want to approach this ? It isn't that hard if you have a few tools. Lots of help here to guide you through.
Let us know.  Also where are you located ?

George

[holes41]

I am located in central Cali (Fresno). Thanks for the quick replies. I was also having some sputter at cruise between 2500-4000 rpm, it has a k&n and old school cobra F1r slip ons. Do you think the stock jetting may be lean for those mods ? If I need parts would 4 of Randy's rebuild kits be the best way to go? I know factory stuff is expensive.

[FJmonkey]

Do you have the stock air box? If you do then stock jetting and needle positions should be OK. 

[red]

first time post , been reading a lot here for almost 2 months before I bought my FJ. After owning an 89 FJ1200 for 3 weeks and loving every minute of it, I have ran into a carb issue that scared me to death while riding today. I was sitting at a red light and noticed my idle slowly dropping and the bike started to stumble. I gave it a quick blip and it revved to 6k and slowly went back to a normal idle and then started to load up again. I rode it home (runs fine above 1500rpm) and fuel was dripping from one of the overflow lines and after 10 minutes I tried to start it and it seems hydrolocked and now my oil level has risen by quite a bit, ok so there is fuel in my oil now, and it's off to a great bike mechanic I know. Could it be a stuck needle valve or float problem, fuel pump? Is this a known issue with these bikes? The bike did this once a week ago but it stopped when I fixed a broken T fitting coming off the front of the fuel tank and tapping the float bowls, I don't know if the T fitting caused the initial overflow or if tapping of the bowls stopped it the first time. thanks for any advice.

Holes41,

The fuel pump should cut off fuel when the key is off, so you have a problem there, also.  Yamaha fuel pumps are pricey.  Some here have used aftermarket auto fuel pumps; maybe somebody here can give you Part Numbers or sources for the right (proven) units.  Beyond that, let us know how you want to proceed on the carbs.  Make sure that the cylinder which hydrolocked gets drained, and gets a shot of new motor oil through the spark plug hole, before cranking the engine.

[holes41]

It dripped for a min or 2. Oil level is up but not beyond top of sight glass, if it was fuel pump wouldn't it still be dripping? I don't have a clue, I just need a beer and a break from these worries. Hopefully not fuel pump

[FJmonkey]

The fuel pump will not push fuel past the needles when they are working properly. So I don't think that is your issue. Fuel will leak out of the bowls until the lever drops below the over flow level. Check to make sure fuel is shutting off with your pump. Remove the fuel line at the carbs, route the line so it is lower than the fuel pump, and can spill into a fuel safe container. Naturally if fuel keeps dripping then the pump no longer checks the flow after the ignition is off. If it stops the fuel then you oil may be safe.

[movenon]

I am located in central Cali (Fresno). Thanks for the quick replies. I was also having some sputter at cruise between 2500-4000 rpm, it has a k&n and old school cobra F1r slip ons. Do you think the stock jetting may be lean for those mods ? If I need parts would 4 of Randy's rebuild kits be the best way to go? I know factory stuff is expensive.

Total rebuild kits ? Do you want to totally rebuild the carbs or just fix the fuel leak ?  If you are just wanting to address the fuel leak then I would just buy:
4 needle and seats
4 needle and seat O rings
4 bowl gaskets

If you want to clean and rebuild the carbs totally,  then yes complete kits. To include emulsion tubes, adjustable needles etc.. Plus I would install new O rings that go between the intake manifolds and the engine as they are cheap and also probably could use them.  There are other optional items that are nice like SS replacement allen head screws.  Randy has them and they can be found at most ACE hardware stores. Typically the JIS screws holding the diaphragm covers and bowls can get buggered up easy.

Have you rebuilt carbs before ? Are you comfortable working on them ?  Like I said they are not hard just a lot of little details which we can help you with.

As far as the fuel pump, when the engine is off then the built in check valve in the pump should shut the fuel off shortly after power is off.
George

[holes41]

I lack the tools and I've only done single carbs on my dirtbikes . With that being said, I had 2 buddies help me load it in a pick up and take it to a well known local bike mechanic who moonlights at very great prices and it is in great hands. Now the 3 of us need some advil and a heating pad, looking forward to getting back on my baby in a week or two. I will update when I hear some news. Thanks

[movenon]

Let us know how it turns out for you.  And if you have any questions be sure to ask. 
George

[FJ_Hooligan]

If your mechanic is going to rebuild the carbs, then immediately order one of Randy's carb screw/o-ring kits and take it to him.  It'll pay off big time in the future.  I'd start off with new o-rings before replacing a bunch of hardware.

[holes41]

do these parts come in the rebuild kits or are they separate?

[movenon]

do these parts come in the rebuild kits or are they separate?

It is in addition to the kits. Some of the O rings are redundant.  The large O rings are the ones that go between the intake manifold and the engine.

http://www.rpmracingca.com/proddetail.asp?prod=carbkit&cat=24

George

[anson45]

Congratulations on your '89 FJ.
A few years back when Upstate New York transitioned from "real" gas to the "E-10" crap I had a similar problem with my FJ. The alcohol in the gas and the glue in the plastic aftermarket fuel filter were incompatible. The glue broke down and became little balls that played hell with the needle and seats: the needles wouldn't seat! My favorite shop only carries brass filters now.
Good luck,
Anson