Carb Rebuild Gas pouring out

[newc4]

I broke one of my posts near the pin and repaired it with JBWeld. Has worked fine for 11 years.

[cywelchjr]

is there a way to distinguish between the two?

The gas ones are longer/wider, and if put in where the vent ones should be they won't vent. But the easy test is to put a hose on them and try to blow into them. If they are good you will get air blowing freely into both carbs, if you don't get that (if it's clogged), then they are blocked and that will/would explain the carbs overflowing. The point is that those MUST have a clear open path between them and the inside of the carb bowls when the carb bank is together, but test it without the bowls on to make sure everything is open when testing.

[mack]

Broken post

which carb did you break the post on?

[Spootinay]

Are you sure the vents aren't plugged? The symptoms are exactly like they are plugged, which can happen if they have the wrong type of T's put in the vent position as they will block the vents. You should be able to blow into the vent lines and the it should blow out into the bowl area with the bowls off. Someone else on here was having the same problem and found the wrong T's on the vents (had the fuel type T's in the vents as I recall) blocking them causing them to overflow. This symptom is exactly what happens if the vent lines are plugged for some reason, so make SURE the vent lines are not plugged.

Congratulations! I had the fuel tee's in the vent holes and visa versa! As soon as I swapped them the leaks disappeared! What a relief!

[Spootinay]

which carb did you break the post on?

It is the post on the #4 carb that the float axle doest have to squeeze into. The piece that broke off did so in such a fashion that the little piece stays in place on its own. I'll be JB welding it soon.

[BA80]

A #2 carb body will work to replace the #4. All you need to do is change the throttle shaft and cap the vacuum advance port.

I have an odd #2 body if your interested.




JAT, I wonder if you put a T in the vacuum hose for the vacuum advance and hooked it to the #2 & #4 carbs if it would smooth out the diaphragm fluxuation a bit.

[cywelchjr]

A #2 carb body will work to replace the #4. All you need to do is change the throttle shaft and cap the vacuum advance port.

I have an odd #2 body if your interested.




JAT, I wonder if you put a T in the vacuum hose for the vacuum advance and hooked it to the #2 & #4 carbs if it would smooth out the diaphragm fluxuation a bit.

I suspect because you would get twice as much vacuum in there that you would get too much advance for a given condition while getting less fluctuation. That fluctuation really goes away in large part pretty quickly, and that wouldn't I think get rid of it, only make it a bit less violent at the expense of too much advance, which would tend to give earlier bikes the same problem later bikes struggle with (annoying 3500 RPM rattle).

[BA80]

The vacuum wouldn't be any higher, just more steady at lower RPMs. Like in an automotive engine.

[cywelchjr]

The vacuum wouldn't be any higher, just more steady at lower RPMs. Like in an automotive engine.

Yes, but that was figured into the system, so more time it the top of the curve means higher overall setting. However, that might not be anything bad. If that worked, it might be worth getting a second set of carbs just so I could modify my carb bank to do that as it would increase the life of the pickup coil wires I'm thinking, so the more I think about it the more I think it's worth trying.

[motoman]

JAT, I wonder if you put a T in the vacuum hose for the vacuum advance and hooked it to the #2 & #4 carbs if it would smooth out the diaphragm fluxuation a bit. [/QUOTE]

Sounds good in theory Greg, but would need a #2 carb in place of #4 in order to utilize PORTED vacuum, otherwise would likely see full vacuum advance at idle.

[BA80]

Read post #66 moto.................

[motoman]

Read post #66 moto.................

True, if #4 was a #2 also..................cyber assumption..........or lack of....

[mack]

sorry

my extra carb body is #3. Gave a #2 away last year, maybe we should pool all our extra bodies to someone centrally located and put together a rack of good carbs which could be sent to members for diagnostic purposes.

[jetmechmarty]

I broke one of my posts near the pin and repaired it with JBWeld. Has worked fine for 11 years.

My bike was repaired that way before I bought it. There's no telling how long it lasted. When the JB failed, the carb flooded. I didn't notice, hit the starter and had a backfire. BOOM! I had a big fire! It could have very easily been the end of my bike.