83 saber flooding issues? What the heck is going on?

So, finally got this running after cleaning all of the contacts from the tank back to the ignitors, etc. Still no tach but i will deal with upfront wiring later. Bike starts, idles a bit rough but I notice that after leaving it a few days, my carbs seem to leak!. Float bowl gaskets are new. Petcock is OFF and it is working properly. I disconnect the fuel line and it is not leaking....but gas is leaking from the carbs. I started it tonight and lots of moisture was pushed out through the exhaust and (I believe there is a moisture vent) the expansion chambers. Even after I shut it down, the exhause was smoking. Wierd. Can sticking floats or something cause the carbs to flood at rest? This is a vacuum starting system so I just don't understand how they could flood if not running. I am worried about too much gas washing the oil out of the cylinders and causing wear. Please help and thanks.
P.S. It is for sale...see Kijiji-Toronto-saber 750. Thanks

 

Leaky float needle/seats will fill up the engine, carb connector pipe tee o-rings dry out and leak outside the carbs.

 

Re needle/seats etc,

Thanks. I will take off the tank and see if I can spot the leaks highest point. That should narrow it down a bit. Really hate taking those carbs out.
P.B.


P.S. When did "freedom of expression" come to defined as "the right to say anything without consideration of others"? Isn't that a type of verbal anarchy?

 

Be happy it's the '83. Early '82's were CRAZY hard to to due to the coolant plumbing. Had to pull it all every time and never failed to tear up O-rings. Not that any Honda V4 carb work is fun.

 

If the fuel tees are leaking you have to split the carbs, I would do it on any bike over 12 years old...I hate fires! As long as you carefully note how the linkages and springs go in place it's not that bad. Here's a pic of my carbs I ran clear hoses from the bowl drains to see what the float level was and to see if it was rising overnight, mine stayed the same (no leaking needle/seats) and it's been running 100% for allmost 2 years, just open the drains and watch that the levels are all about the same taking into account carb slant. After complete rebuilding I did a bench sinc with a piece of thin brass strip in each butterfly to get them close, it ran nearly flawless, I later syncronized them with mercury stix and only 1 was off about 1 bar. Mine went on easy with new intake manifolds and silicon spray $30 but worth every penny for the ease of reassembly. I set the manifolds in the sun to make them soft as possible. Best of luck!

 

This may sound slow but if I understand, you opened the drains after attaching the lines to see if they continue leaking after initial draining? I guess a complete cleaning is in the works. Annoying but dooable/eally wish Honda had run individual lines to each carb as those connectors are too brittle and hard to find. Question; If it is not the connectors, or loose screws, should the carbs continue filling if the bike is at rest? That's the part i don't quite understand. Also, is the moisture coming out the back end essentially unburned fuel? I am checking the coolant and oil later to make sure there is no cross contamination indicating internal seal issues (and a definate reason to sell it off as I willnot have time or experience to deal with those). Thanks

 

Note (keep in mind my carbs in the pic are upside down) With the lines going up the side of the carbs no fuel will come out even thou there open (providing you run them higher than the fuel level), the fuel in the tubes will just seek the same level that's in the carb, like a old coffee machine with the plastic tube up the side to tell you how much is in the thing. The Fuel TEEs on mine weren't brittle I twisted on them to make sure they wouldn't break, but the o-rings would leak if I even bumped the fuel line. If the float valves (needle/seats) leak whatever is in the lines can fill the carbs (one or more) and overeflow into the cylinders. Normally with the fuel off it shouldn't be much. You may just have moisture in the exhaust, we don't have alot here in AZ but there can be alot in some conditions. If it's flooding it should require holding the throttle open to get it started and maybe some black smoke. If it starts and idles fine without clearing it out it's not flooding after being shut off.

Last bike I had with flooding carbs was my GPZ550, if you left it on reserve when you parked it the engine would fill with fuel (lots of fuel) and it was very hard to get started (flooded condition) and I would have to change the oil due to the contamination. Some of the Automatic OFF petcocks actually flow fuel if left in the reserve position and of course the prime position. That's how I bought my GPZ550... 900 miles on it, my brother in law bought a new $50 Petcock, installed it put in a small amount of fuel put it on reserve or prime and ran it , he shut it off and the next morning it was full of fuel again so he gave up, he had left it on reserve or prime.

 

O.K. So i decided to drain the oil just in case there was fuel contamination. The oil poured out and was very watery and smelled of fuel. I drained about 6 litres...guess that's why my fuel tank was so low. i just don't understand how it could've flooded so badly. i am removing the carbs to rebuild.
I poured in some fresh oil to chase out the contaminated stuff and will be adding some fresh oil directly into the heads through the plug holes to be sure there is good oil in there, then turn it over (no fuel or plugs attached) to make sure things are lubed. Just don't want to wreck the engine. Does this sound like a plan? Any ideas about teh cause of the flooding would be appreciated.

Thanks

 

That sounds like a plan, can't hurt. I think the 83 sabre is a manual petcock, (not vacume operated) check in the off position and be sure it's off. That only leaves the carbs as the culpret. Sounds like a float needle seat problem, be sure to check the floats and make sure there's no fuel in any of them, thou rare I have seen some floats that leak and get heavy. Try Billy Carr (link below) for parts, I bought needles/seats from him years ago $30 shipped for all 4 sets. Make sure your tank is spotless and a fresh filter, rust particles cause floats to stick and that means removing the carbs on a regular basis for cleaning.

Billy C's more or less complete price list

 

re flooding etc

Vacuum petcock. Was left on for 4 days last week and maybe that started the problem. I ahve removed the carbs, taken off valve covers to inspect. Poured clean oil onto the valve tops/stems, cam lobes, timing chains and also a bit into the plug holes to be sure there was soemthing in the cylinders. Cranked it a bit and tested compressionj with my thumb. sems fine. Going to let it sit for about 5 days as we are heading down to South Carolina for a vacation. Question (hope it isn't too stupid) but can a tight valve cause a perpetually open issue (constantly sucking in fuel while cranking)? They seem o.k. as per measurements. Any advice appreciated as I really don't want to wreck the bike or write it off as parts.

Peter

 

re flooding etc

Vacuum petcock. Was left on for 4 days last week and maybe that started the problem. I ahve removed the carbs, taken off valve covers to inspect. Poured clean oil onto the valve tops/stems, cam lobes, timing chains and also a bit into the plug holes to be sure there was something in the cylinders. Cranked it a bit and tested compression with my thumb. seems fine. Going to let it sit for about 5 days as we are heading down to South Carolina for a vacation. Question (hope it isn't too stupid) but can a tight valve cause a perpetually open issue (constantly sucking in fuel while cranking)? They seem o.k. as per measurements. Any advice appreciated as I really don't want to wreck the bike or write it off as parts.

Peter

 

If you open the petcock with the fuel line removed and the engine not running, does fuel flow out? If so, someone has most likely converted the petcock to gravity operation. The fuel in the crankcase is most surely the result of overflowing carbs due to the float needle(s) not seating and failing to shut down fuel flow.

 

The valves being tight can't cause flooding, but a bad needle/seat... one or more will fill the engine with fuel when the petcock is left on, if the petcock is off and working (shutting off fuel flow) only what's in the fuel line could go into the carbs. The floats needle/seats work like a toilet bowl, if they don't shut off fuel flow when the bowl reaches a certain level if overflows into the carb throats down into the cylinders then seaps past the rings into the crankcase and contaminates the oil. This is a very common thing with carbs.

 

+1 I just went through a similar problem because my bike had been sitting for a couple of years. The float valves were all corroded, split fuel line at the tees, etc. Cylinders filled with fuel when I tried to start it. I replaced the float valves, and flushed all fluids. So far so good.

 

How do they sell them so low?

And how did you get those carbs so clean? What's your secret formula?

the professor and poindexter have stolen the secret formula...Felix