Weber flooding problem....

Thursday, 31-Aug-2000 21:25:39

Message:

24.93.204.125 writes:

I have been reading posts about people having problems with Weber IDF's flooding after the engine is shut off. Well, I have been having this same problem for years progressivly getting worse each year. This year was the worst yet. So bad that the valve covers have raw gas in them when removed to adjust valves. Once this year I couln't even start the car due to hydraulic loc. Had to hand crank the engine backwards by hand to clean it out. Some people say it is percolation or boiling of the gas due to a hot running engine which seemed to be true and believable. I tried to lower the float level to help but it only made the motor run like crap and still flooded. Well last night I had the carb tops off to reset the float level adjustment and I took a good look at the needle valves and noticed some slight wear on them ( very small). So I removed the little plastic retainer caps and lightly chucked them in a drill (mini lathe). I carefully sharpend the needles with 1500 grit paper until all wear marks were gone. Today the car ran better than ever. Lots of hot driving ( yeah, we hit 90 in Ohio today), starts and stops ( gas stations, fast food...) no more flooding. Hit the key and all 4 are fireing at idle. All right, no more stained manafolds, fould plugs, worn out rings, etc.....

Ohio Tom

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Drooling IDF's....

Sunday, 29-Oct-00 20:05:57

204.210.216.234 writes:

I have one final ( yeah right) problem that I would like to put an end to: My 44IDF's continue to have a flooding problem after the car is shut off.

Had the same problem for several years now continuing to get worse each year. This spring I thought I had it solved when I dressed up the float

needles. This worked well for about 2K mi. But now the problem is back with a vengance. Every time I go to start it up no matter how long it has

been sitting, she missed on one or 2 cyls for a few seconds. Lots of smoke util she clears up. Someone once posted that the springs inside the

needles gets weak and needs replaced. Could it be this simple? I have checked and re-adjusted my floats with no change in the problem. It seems

that residual fuel pressure is bleeding past the float valves and running down the throats. Always #1 and 3 as my car has a slight rake to it. Anyone

esle have this problem too? I am planning on pulling the carbs ( engine too) now that the weather is too cold for driving.

Ohio Tom

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Replies:

Tom, what fuel pressure and what... (Greg Ward) (29-Oct-00 20:14:19)

are you sure its the carbs?? did you actually look down them after shutdown and see fuel dumping?? the fuel shoud evap. over night [the eng is still hot]shouldnt have prob in morning.

what color is smoke?? sounds like oil fouling to me... pull plugs and check in morning ... dennis valley vw (n/t) (29-Oct-00 22:00:33)

New stocik fuel pump.......Yes I have seen the fuel dripping down the throats after shutoff. No, it doesn't evaporate. I have pulled the manafolds off and seen about 1/2oz of fuel laying

in the intake port (if the valve happens to be closed). Black smoke...Fresh motor with new rings, no blue smoke. Greg, I just got the kit last week. I can't believe they shipped it air mail

for $8AUS. Still took some time to clear customs. (n/t) (Ohio Tom) (29-Oct-00 23:28:10)

Re: Drooling IDF's.... (mood) (30-Oct-00 08:15:27)

Tom, I had this problem as well, and posted back when you made your needle and seat adjustments. More>> (Jim Brown) (30-Oct-00 10:49:49)

Jim's post probably has the answers to your problem, but also check that the gas tank is properly vented. If not, pressure may build up in the tank while driving, and when you shut

down it can force fuel past the fuel pump diamphram into the carbs. (n/t) (george brown) (30-Oct-00 12:14:02)

Re: Drooling IDF's.... (Stephan) (30-Oct-00 14:55:53)

HEY YOU GUYS I HAVE THE ANSWER. jeff n and i found that there is a bleed hole above the idle jet under the air filter lid, it gets air by way of a passage. we tried everything

and my car still drooled. then he got to lookin at the lid and that little bleed had a little pebble in it. he stuck a wire in and the pebble wen t CRUNCH that was it no more drooling. why

i have many theories so does he. think about it and write me. :) (n/t) (dave from redding) (31-Oct-00 02:56:56)

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Re: Drooling IDF's....

Monday, 30-Oct-00 08:15:27

195.39.134.82 writes:

If you have a mechanical fuel pump, it won't be easy to check for actual overflowing unless the engine is running or just shut down like you say.

Just change the needles and seats and that will be the end of the problem. Your carbs also drool while running so you wiil see a big improvement in

fuel metering. The springs I was talking about before allow the float level to get too high if they are too soft. Even if the float bottoms out on the

carb gasket(provided the needles don't have a sealing problem), it won't overflow, but causes richer mixture. New needles and seats will take care of

that too.

mood

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Tom, I had this problem as well, and posted back when you made your needle and seat adjustments. More>>

Monday, 30-Oct-00 10:49:49

207.191.66.157 writes:

I came to the conclusion that mine was strictly related to percolation. As a recap: shutdown, carbs "warm" to the touch, 5 minutes later, carbs

getting hot to the touch, a few minutes later, percolation. If I looked closely, the fuel would be coming out of the progression holes, meaning the

"boiled" gas was "boiling" up through the idle ports, back down through the progression holes. At this point, you could not hold your hands on the

carbs (too hot). Phenolic spacers lessoned the problem (actually delayed the boiling point). My problem, inevitably, was a poor engine/head/exhaust

combination causing excessive head temps (unfortunately, I never had a gauge, nor did I record any numerical data on the head temps - all by feel,

sorry). Having corrected the head porting problem, different (larger exhaust), and an overkill on the cooling system, my problem with IDF

flooding/percolation is completely gone. I feel confident in my testing thus far, as I have had many long duration drives with the temps in the mid to

upper 80's; same conditions when I had these problems. - Jim

Jim Brown

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Re: Drooling IDF's....

Monday, 30-Oct-00 14:55:53

205.188.192.41 writes:

I had exactly the same problem on my 48's!!!

Chech the fuelchamber for a whole that is drilled near the chanel for the jets.

There should be a slight "bump" with the whole drilled exactely in the middle. With my carbs they where just off centre resulting in fuel leakage, due

to fouling another channel.

My carbs were replaced by Webber without charge!

PS: tried everything did not work until a specialist checked my carbs!Good luck!

Stephan