Carb leak between carbs 1 and 2

[ajs350]

I have not been riding my 80 much lately so when I took it out the other week and I stopped some 10 minuets later I found fuel dripping from between carbs 1 and 2. I took the bike home where it was still leaking. The following day I went to investigate but could not replicate the leak. Yesterday, however the problem returned.
I suspect one of the o-rings is shrinking and then expanding but before I seek out a supplier could this be caused by something else?
Thanks
Ross

[tevan]

I think you hit the nail on the head. Time to pull carbs.

[Larry Zimmer]

That would be it, Ross. Unfortunately, the only known fix is to separate the carbs and replace the orings. Be certain you use Viton material orings if you do it yourself. It takes temperature better, ages better and handles ethanol better.

[steve murdoch icoa #5322]

Are you positive it is coming from between the carbs and not a leaking float bowl.
Just another spot to check.

[ajs350]

Are you positive it is coming from between the carbs and not a leaking float bowl.
Just another spot to check.

Good idea but unfortunately no luck. I've ordered the Viton o-rings as Larry suggested so it looks like the carbs are to come off. Never split them before so this will be a new experience!

[Larry Zimmer]

Not all too difficult, Ross. A manual (which I believe you have) is quite useful. Biggest thing (for me) was to be very observant of the linkage in the center where things 'join'. Be a bit careful of the choke linkage. Some of those bits are not exactly boiler-plate. There is quite a bit of material in the forum. Do some searching. Also, feel free to write. I had the same problem -- the orings on the feed pipe between #1 and #2. And, when re-installing, use hi-temp silicone on the carb nipples and a thin film on the boots. Be certain to seat the carbs all the way against the shoulders. Check both sides. One goes in and the other pops back out. Not too bad to get them though. Just a little pushin and shovin.

OH, YEAH -- be certain to have all the cables attached and routed BEFORE you reinstall. Just can't do it afterwards. And, vice-versa when removing. Don't try to pull the cables with the carbs in-place. Just drag it all out together. When detaching the cables from the throttle grip, first put a lot of slack into the 'on' cable using the adjuster that is under the tank.

You'll 'learn' a lot the first time through. Good stuff, though.

[ajs350]

Thanks Larry. I'll be sure to reach back out if I get stuck!
BTW this is what I bought. http://www.ebay.com/itm/honda-cbx-cbx10 ... 26&vxp=mtr
Is this all I need or are there other parts I should have to complete the job?

[ajs350]

Big mistake today - instead of taking the screws out of the choke plates I took them out of the throttle plates. They were a bugger to get back in and being as they were "staked" before I'm worried they might come out. Any suggestions to ensure they stay in place or am I worrying about nothing? Thanks. Ross

[daves79x]

You have to really get the throttle plates centered or you'll have problems. Call me and I'll walk you through it.

Dave

[herdygerdy]

Before you put the carbs back together, it is a good idea to spray carb cleaner into the accelerator pump circuit on each individual carb to check the small brass nozzle located at 5 o'clock in the throat of the carb is not blocked. The hole is REALLY tiny.

If blocked, they can be a REAL bear to unblock, but here is a tip that works very well indeed and has got me out of deep doo-doo many times.

On 78-79 carbs, they use a rubber plug inside the float bowl that is the perfect size to fit either side of the casting hole of the accelerator pump circuit on the side of each individual carb.

Like so.....



Put one in on one side of the carb, then flip it over on the bench and carefully top the circuit up with carb cleaner.

When it is full to the brim, put the second one in right on top of the carb cleaner. The trick is to try and have no air in between the two rubber plugs. Then get yourself a big ol' pair of multigrips and use them like this and squeeze firmly.

Hydraulic pressure built up when you squeeze the plugs and carb cleaner does the hard work of quickly unblocking the jet.




And when re-assembling pairs of carbs together, this trick with match sticks makes it a whole heap easier as the small pieces of match stick are pushed out backwards as the carb butts up nicely with its neighbour.....







And ready for the final push together....



Some folk use cut up O rings as well, but I find the square faces of the match stick seems to work better at keeping the washers separated, but parallel.

Hope this helps with putting it all back together.

Cheers..Tony.

[ajs350]

Before you put the carbs back together, it is a good idea to spray carb cleaner into the accelerator pump circuit on each individual carb to check the small brass nozzle located at 5 o'clock in the throat of the carb is not blocked. The hole is REALLY tiny.

If blocked, they can be a REAL bear to unblock, but here is a tip that works very well indeed and has got me out of deep doo-doo many times.

On 78-79 carbs, they use a rubber plug inside the float bowl that is the perfect size to fit either side of the casting hole of the accelerator pump circuit on the side of each individual carb.

Like so.....



Put one in on one side of the carb, then flip it over on the bench and carefully top the circuit up with carb cleaner.

When it is full to the brim, put the second one in right on top of the carb cleaner. The trick is to try and have no air in between the two rubber plugs. Then get yourself a big ol' pair of multigrips and use them like this and squeeze firmly.

Hydraulic pressure built up when you squeeze the plugs and carb cleaner does the hard work of quickly unblocking the jet.




And when re-assembling pairs of carbs together, this trick with match sticks makes it a whole heap easier as the small pieces of match stick are pushed out backwards as the carb butts up nicely with its neighbour.....







And ready for the final push together....



Some folk use cut up O rings as well, but I find the square faces of the match stick seems to work better at keeping the washers separated, but parallel.

Hope this helps with putting it all back together.

Cheers..Tony.

Now that is an awesome tip Tony. Just wish I'd known about it on Saturday . Getting those sync mechanisms to join up was the most testing part of the rebuild.
All is back together now and running well despite my screw up with the throttle plates. Of course my 911 call to Dave had me on the right track and I was able to follow his instructions on how to re-seat them and bench sync. You just don't get that kind of information from the manual. Cheers Dave.
I have to admit I was a bit apprehensive about splitting the carbs for the first time but encouragement from Larry and others here had me bite the bullet. So glad I did. Thanks guys. Ross

[Larry Zimmer]

Good to hear you're on the road, again, Ross. Enjoy the ride!

[herdygerdy]

Great to hear you got it all solved Ross, and that you are back on the road.

Sorry my post came too late and that you had such a bear putting the carbs back together.

At least now you have the confidence and skill to dive in to them as and when needed.

As they say in the classics....."Knowledge dispels fear".

Enjoy your freshened up ride.

[NobleHops]

Thank you Tony, your contributions are excellent as usual.

[CopperCollar]

Now I can't wait to try the match stick trick on the next set of carbs!

Mike