carburetor problem fuel - heavy flood

deQuincey

deQuincey

Quousque tandem...?
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if you permit me i will place here your answers to my question that has been mixed with another issue from our new friend scottevest

61porsche said:
Flooding- running with heavy flooding can wash the cylinders of oil. This in turn can damage the rings resulting in a loss of cylinder pressure due to ring seal in short order. It can thin your oil; not good for valvetrain, bearings, etc..it's better to stop, pop the top of the carb off, fix the float; usually just hung up open.

If you notice a big drop in power, all three cylinders on that carb can go out. That big 6 can run on three, but your foot is going to be deep in it.( pedal halfway.) It also can wash junk off the valves and into the bores causing the opposite problem- stuck rings, junk on valve seat, etc. Stop, fix the float.

If you run carbs, always... carry a screwdriver, allen wrench, and a 13mm wrench or crescent. Feild stripping a carb is better than an engine rebuild. You don't have to remove the carb from the manifold and it shouldn't take long.

This isn't a normal occurrence on Zeniths. But if it happens and your far from home... stop. Around the block, sure. Head for the barn.

No on the solenoids. Usually they stay closed if malfunctioning and you would know it by the engine running noticeably rough. The idle circuit might have a little fuel left if jammed opened but when the engine shuts off the fuel does too. Biggest problem with solenoids is the wire falling off or being accidently hit.
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Last edited:
answering your questions:

61porsche said:
Flooding- running with heavy flooding can wash the cylinders of oil. This in turn can damage the rings resulting in a loss of cylinder pressure due to ring seal in short order. It can thin your oil; not good for valvetrain, bearings, etc..it's better to stop, pop the top of the carb off, fix the float; usually just hung up open.
i checked the oil today, it has been slightly thinned by the fuel, and it has fuel smell on it
so today i changed oil and oil filter, so yes it was a bad idea, but anyway it was only 10 miles

If you notice a big drop in power, all three cylinders on that carb can go out. That big 6 can run on three, but your foot is going to be deep in it.( pedal halfway.) It also can wash junk off the valves and into the bores causing the opposite problem- stuck rings, junk on valve seat, etc. Stop, fix the float.
well yes, i assumed immediately that i was running on three cylinders, so i came very slowly in second gear

If you run carbs, always... carry a screwdriver, allen wrench, and a 13mm wrench or crescent. Feild stripping a carb is better than an engine rebuild. You don't have to remove the carb from the manifold and it shouldn't take long.
i will try to open the front carb (my family does not leave me the required time for it, so we will see)

on the other hand the engine rebuild is programmed for september, i have the place for it (a friend lends me a crane and a place with an adequate opening in the floor) and the list of parts, also the engine rebuilding shop has been contacted and everything is ready

remark: the reason for the rebuild is the oil consumption together with a tickling noise of cylinders number 2, and 4 when the engine is cold (probably rings, but i am prepared for new pistons if necessary), the expert in the rebuild shop checked it with a stethoscope

This isn't a normal occurrence on Zeniths. But if it happens and your far from home... stop. Around the block, sure. Head for the barn.
what about reworking the floats ?, i mean, i remember sharp and square corners, so i am thinking about some sandpaper polishing

No on the solenoids. Usually they stay closed if malfunctioning and you would know it by the engine running noticeably rough. The idle circuit might have a little fuel left if jammed opened but when the engine shuts off the fuel does too. Biggest problem with solenoids is the wire falling off or being accidently hit.
Click to expand...

thanks
 
DQ,

The float shouldn't be altered. It has a specific weight that's important to fuel level. I've tried to epoxy a float before; it wasn't a success.

If you study the angles of the float and the corresponding angles in the bowl they are complimentry or matching. When trying to set the optimum float level and altering sealing ring thickness on the inlet float valve the tendency to increase the ring thickness can be a great tempation. Too much and the float hangs up or open. There once was an E3 FAQ on carbs that suggested a shim around the hinge pin resting in between the float and the valve. I've done that too; but not successfully for long.

One more word of caution; when refitting the float/ jet section be careful to hold the float closed as much as you can. It's easily damaged after all these years and they're not cheap or readily available around the corner.

With all the gas formulas at different times of the year or location, the specific gravity of the gas alters the float level. ( remember the float was designed a long time ago when gas was leaded; now a days 10% ethanol is common.) Couple that with a slug of water from mixing with the alcohol and it's not hard to imagine how a float hangs up and goes wacky.

In cold climates where cars are stored for winter, we always topped off the tank and added a stabilizer additive if it was for long. Condensation happens sometimes in the tank.

Use gas that you know to be consistant in quality. If the carbs are acting up it can be the tank or gas. No matter what fuel filter, you can have finer particles of crud pass through and deposit in the bowl. I've seen red, brown, and white junk in carbs.
 
all refited and cleaned up, apparently no visible problems
car started ok, and no flood was present
i am not satisfied because i do not know when it will happen again
thanks
 
message to mr.61porsche

hi jerry :-D:-D:-D

great !

i have found a very interesting sympthom, probably the cause of the problem of the heavy flodding !!

when i oppened the spare carb that i have in my shelf, trying to find a cause, i found that the floater was blocked inside, i shake the carb, and nothing moved inisde, so the floater was blocked !

so i opened it, and i found the following situation, the gasket flange was very big in that area and it was blocking the floater in the "lower" position, the gasket flange was interferring the side of the floater

as the floater is in that position, that means that for sure the valve is not stopped, and the fuel flow will continue

in the following pic everything was moved, but you can see the contact interference points between green and red arrowed areas
030320072636.jpg


in this pic you can see the gasket excess that surpasses the carb body (it is in between red arrows
030320072637.jpg


it is really possible that this is the cause of the erratic behaviour of the floater, i mean the flodding was not always happening, normally the situation was the following:

hot weather, i stop the car for more than 1/2 hour, then i start the car, run a little and then rough engine (now i know that it was running on three cylinders). Explanation: the little run is sucking the fuel in the reservoir and the floater wents really down and in its way up it becames blocked in the gasket flange

surprisingly, if i stop the car until the next day, the engine works again

it is a great discovery, because that means that if i make that gasket excess dissapear (cutting it with a sharp knife), i will eliminate the cause of the flodding problems, right ?

do you agree ? have you heard about this ?

regards

ps. i will have to check it in my "problem" carb in the car
 
Yes sir.The kits come with several gaskets that are close, but not exact. It's terribly important to save your old gaskets for comparison. There's one more that has an extra hole that's easily mistaken too.

Trim the gasket so the float won't scrape it and hang up.
 
and also make sure the float is centered in the bracket that holds it down at the pivit point - not too far off center one way or the other.
 
61porsche said:
Yes sir.The kits come with several gaskets that are close, but not exact. It's terribly important to save your old gaskets for comparison. There's one more that has an extra hole that's easily mistaken too.

Trim the gasket so the float won't scrape it and hang up.
Click to expand...

ok, just to close this issue properly,

the gasket was trimmed carefully with a dremmel tool, that ate a little of the aluminium block too, all material removed help avoiding the contact with the floater, all this was made very carefully to avoid any damage

and, i have to say that after 2 months and 1000km, the problem has completely dissapeared !!!

good !!
 
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