New Member with a leaky bike

[FrizzleFry]

Hi everyone. I purchased an '89 1200 (38K miles) about a month ago. Previous owner had alot of work done (I know the mechanic) and the bike has run really, really nicely up until last week when I noticed fuel dripping out. Once warm it started to bog and wouldn't idle. I found fuel in the oil, drained it, re-filled and the bike ran perfect on a 10 mile ride. The following day I started it up and it again ran perfectly. Yet there is still fuel dripping from somewhere . The carbs were rebuilt and the bike runs perfectly otherwise. The bike was on it's side-stand for about 2 weeks without being run just prior to this happening, the mechanic said that could be an issue but I'm not sure how. I thought I would remove the tank and see if there's any damaged hoses or anything odd. I guess my question is if there was something wrong internally with the carbs, would the bike run as good as it does? I'm somewhat mechanical but I have never torn into motorcycle carbs before and I'm not entirely familiar with the inner workings. I searched and saw many posts about leaking carbs but none that really fit my description. If I understand correctly, on models with a fuel pump, the flow should stop when the bike is shut-down correct? Anyway sorry for the long post, just hoping I can get some help. Thanks in advance, and I've really enjoyed the forum so far.

[FJmonkey]

I will let the carb guys answer your questions, welcome to the FJ brotherhood.

[FrizzleFry]

Thanks!!

[FeralJuggernaut]

I run an '84 with a gravity feed, so I may not be exactly on here...   I am thinking mulitple issues potentially.  Petcock not shutting down the fuel flow when bike is off.   I would think that either a float is stuck open and/or there is a leak around the o-ring that seats the needle valve.  Both of those are the most frequent offenders in this scenario.   The part about gas in your oil is my bigger worry.   You should have (at least the FJ1100 does) some over flow hoses that come down off of each carb for just this kind of error mode.  I'd wager they are kinked or bent upwards enough to not allow that over flowing carb to vent to the ground.   If you get far enough into it,  ID each of the 4 hoses, I suggest labeling them for future reference.  Then you'll know which carb need the TLC if/when it happens next time.  This is the short version to get you thinking and poking around until the official  Dr. Carb has time to check on us.     Good luck and let us know your findings.   

[andyb]

Hi everyone. I purchased an '89 1200 (38K miles) about a month ago. Previous owner had alot of work done (I know the mechanic) and the bike has run really, really nicely up until last week when I noticed fuel dripping out. Once warm it started to bog and wouldn't idle. I found fuel in the oil, drained it, re-filled and the bike ran perfect on a 10 mile ride. The following day I started it up and it again ran perfectly. Yet there is still fuel dripping from somewhere . The carbs were rebuilt and the bike runs perfectly otherwise. The bike was on it's side-stand for about 2 weeks without being run just prior to this happening, the mechanic said that could be an issue but I'm not sure how. I thought I would remove the tank and see if there's any damaged hoses or anything odd. I guess my question is if there was something wrong internally with the carbs, would the bike run as good as it does? I'm somewhat mechanical but I have never torn into motorcycle carbs before and I'm not entirely familiar with the inner workings. I searched and saw many posts about leaking carbs but none that really fit my description. If I understand correctly, on models with a fuel pump, the flow should stop when the bike is shut-down correct? Anyway sorry for the long post, just hoping I can get some help. Thanks in advance, and I've really enjoyed the forum so far.

Pop the bits off and see where the fuel's coming from.  I've got a 90, so functionally the same, albeit I'll bet mine's in more pieces than yours!  

Fuel leaking is probably coming from the bowl overflow vent, when warm it'll bog because there's too much fuel in the bowl (prolly one, but possible to have issues on several at once!), and lack of idle is because it's pig rich with the fuel sitting so crazy high.

Your float needle, needle seats, or (most likely) the o-rings that the float needle seat rides in is/are crapped out, most likely.  Once you hit nearabouts half throttle it should clear its throat and threaten to take your shoulders out of socket.  It should also easily run right up to speeds that cause cops to pull you over and club you like a baby seal.

This shows the float needle seat, this shows the oring that is most likely the culprit, this shows pictures that roughly explain what you'll need to do to get to that point, this tells you what size orings to get, and this kit includes the proper ones, though if you have the SS hardware already you could get this kit, but it'd be overkill (and you'd want 4, they're not inexpensive but fix basically everything, maybe desirable at 38k but prolly not).

On the fuel pump equipped models, the petcock isn't vacuum operated, fuel is controlled by the pump not allowing flow when off.  In theory your pump could be bad, but it strikes me as somewhat unlikely compared to the seat orings going to pot.  It's also possible that there is a stuck float, if that's the case you can just tap on the carbs (smallish hammer and a longish wooden dowel would suffice nicely, have some care though), and it would go away.  If it doesn't go away, it's very likely fuel leaking past the float seat assembly in some form or another.

[FrizzleFry]

Thanks very much for your input and advice, and the helpful links. I removed the tank today and found the leak. There are 4 hoses that come off of each carb, then 2 larger ones on either side that connect to what looks like a plastic fitting between the outer and inner carbs. It appears that most of the fuel is coming out of the larger hose, but only on the right side of the bike (sitting on it) the one on the left kind of runs along the frame instead on being routed down like the right one, and it's dry. There appears to be some fuel coming from a few of the smaller hoses as well. Can you tell me what these hoses are for? Sorry to be so lame but I have little experience with bikes like this and I've yet to get my hands on a manual. Thanks again in advance for any help you can provide. I would very much like to repair this myself and not take it back to the mechanic. I am a little disappointed that he charged the previous owner to rebuild the carbs and didn't address these potentially failing parts. Then again, it didn't do this the first few weeks I owned it.

[FeralJuggernaut]

The 4 smaller hoses are bowl over flow for fuel.  Believe the 2 larger are for air pressure equalization.   If you are going into them yourself, do me(us) a favor and get that $22 kit of stainless screws and o-rings.  I promise there isn't a better investment in your FJ than that for anything under the tank!   Allow for all the time in the world and follow that other thread, particularly the document in the link.    On carb day at my garage, 1 hr to get the carbs out, one hour per carb for detailed cleaning and double checking, and about an hour to put it all back together.  (I have stock airbox for the extra level of difficulty    )    When you've done it a few times, cut the estimates in half.  Nobody cares more about your carbs than you do and being familiar with the workings will bring an extra level of ownership happiness.   I do mine about every other year with the crappy Phx fuel additives.  You can do it!   

[FrizzleFry]

Thanks again guys. I'd love to go in and do these things myself, but I just don't know if I'm ready for it. Looks like I may have no choice though. Adjusting the floats and the syncing is a very scary thought for me. I'm going to talk to the mechanic who rebuilt them a few months back and see if he replaced the o-rings. Once I got the tank off I could see that he had done everything else he charged for so I have no reason to believe he didn't do a proper job on the carbs. Or could be he was just able to adjust them well enough for it to run as well as it does. It would be nice if these fuel pump models had a shut-off to keep the pressurized fuel from continuing to dump in. I could splice one into the line but access would be tricky. Thanks again for all the help and I'll keep you all posted.

[andyb]

It would be nice if these fuel pump models had a shut-off to keep the pressurized fuel from continuing to dump in.

How exactly do you think a fuel pump works?  When the key turns off, the fuel stops being pressurized.  The stop for the fuel going into the carb is at the float needle tip, float needle seat o-ring, the check valve within the pump, and the petcock if you really want to pull the tank in the air.  It's more than enough!

But after over twenty years, rubber that's been basically soaking in solvent is going to wear out and not work very well anymore.  Shocking!  I wish half the crap in my house would last 20 years without any mainenance!

[racerrad8]

The 4 smaller hoses are bowl over flow for fuel.  Believe the 2 larger are for air pressure equalization.

Close, but not quite...

The four small hoses are the fuel enrichment (choke) circuit vents. The two large hoses are the overflow tubes.

Thanks again guys. I'd love to go in and do these things myself, but I just don't know if I'm ready for it. Looks like I may have no choice though.

There is always a choice. You can send them to me, I will rebuild them, properly. I have all of the parts and tools to do the job correctly the first time. I have built many sets for members, including the big guy, here and they have all been happy with the service and quality when they get them back. I just sent a set back to lomojo a couple of weeks ago after he had them apart several times. I got this email back today;

message: my fj buddy
i am a little late with a thank you,due to family emergency's but i thank you so much for solving all of my problems.
the fuel pump works perfectly,the carb build was spot on,3&4 needed the smallest of
calibrating with 1&2.
i am more than satisfied with your recommendations.She runs beautifully.
You Are My Hero
Thank you again
Your Avid Fan

Shoot me an email and I would be glad to help you too.

Randy - RPM
randy@rpmracingca.com

[andyb]

...and found the leak. There are 4 hoses that come off of each carb, then 2 larger ones on either side that connect to what looks like a plastic fitting between the outer and inner carbs. It appears that most of the fuel is coming out of the larger hose, but only on the right side of the bike (sitting on it) the one on the left kind of runs along the frame instead on being routed down like the right one, and it's dry. There appears to be some fuel coming from a few of the smaller hoses as well. Can you tell me what these hoses are for?

1-  Cylinders are numbered for reference.  When sitting on the bike, #1 is to your left, #4 is to your right, and the middle ones are in order.  So you're having fuel coming out between 3+4.

2-  Read this which explains which bit is what in that area.


Pulling your carbs and fixxing them isn't a hard job, probably take a good solid afternoon's worth of work and around a six-pack of good beer to finish.  Drinking cheap or light beer is asking for trouble though.  You will need a basic tool kit and the ability to know how to use most of it.  A bigass philips screwdriver (#1 or so), a set of vice grips (locking pliers) or an impact driver if there's frozen screws, a smallish screwdriver or punch, something to hit things with (a small hammer or whatever's handy at the time), a few various flat screwdrivers, a couple cans of carb cleaner, a dental pick or knife with a nicely pokey tip, decent lighting, decent eyes (or a set of cheaters or magnifying glass), a handy computer with the carb cleaning walkthrough + pictures handy, eye protection and possibly gloves, a place to work that's reasonably clean (card table in the garage works well, but you can MELT the tops of some of them, ask me how I know...), and a bit of patience.

If you're missing any single portion of that, send them off and have Randy run them through his routine.  Be warned that they'll be all clean and make the rest of your bike look very dirty and old by comparison, so you'll end up giving the entire damned thing a good scrubbing.

Once they're back on, you're going to need a synch tool or a dealership and a fistfull of cash that you don't want anymore.  Doing the synch isn't hard, but the difficulty is directly proportional to the quality of the tool you're using.  Twenty feet of clear tubing for an aquarium and some ATF or gear oil will get the job done for a couple bucks, but spending $100ish on a Morgan unit makes it a walk in the park.  This is not something that can be done by remote (Randy won't be able to do this for you unless you ride the bike there).  Where are you located?  If you're willing to travel and buy beer, odds are there's a member that has the tools and can walk you through it within a decent range.

[racerrad8]

...This is not something that can be done by remote (Randy won't be able to do this for you unless you ride the bike there).  

On the contrary my good sir, I have a vacuum checker that I can set the sync on the carb on the bench. This sync sets the throttle plate angle perfectly. In 99% of the carbs that I send out they are less the 1" Hg off of sync on the bike.

He would be able to bolt them on and ride without any issue.

That is why I stated I have all of the tools; ultrasonic cleaner, removal tools, sync tools plus all of the parts required to make the 100%.

Randy - RPM

[andyb]

Not true if his valves aren't also adjusted very close though, as then each carb would see different vacuum signal, no?


Actually, come to think of it, can you compensate for different rpm when you set it?  For example, some people want things synch'd at say, idle, vs some wanting is sync'd at 3k or whatever.  Is there a way to mock that with the tool, as the engine isn't necessarily going to be linear for each cylinder's air demand?  That'd be a damned neat thing to have handy!

[FrizzleFry]

Thanks to all!! To Andy - that was really inspirational and also very funny, I deserved the fuel pump slam but I was thinking more in terms of being able to get rid of what gas was left in the line, say if I had a shut-off inline so I could turn it off then run the bike for a few to empty the line so that when and if you did have a problem you wouldn't have puddles of gas in the floor stinking up the place. My thought was that the line is still pressurized after killing the engine so there's still some fuel pressure, but I may be wrong.  I think I will attempt the rebuild myself if I can't afford the services of Randy. With so many great resources you guys have provided how could I go wrong?? Thanks again guys and I'll keep you posted.

[andyb]

Any pressure left in the line is minimal at best, and at least on mine, would stay in the lines, as they were mostly below the level of the float needle.