Flooding after shut down

Carbs & F.I.

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MidWesty
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Flooding after shut down

Post by MidWesty » Sun Nov 12, 2006 6:34 pm

I've got a '73 Double cab w/1641 34Pict3 set up.
The carb seems to be flooding after I shut the engine down. Doesn't matter how long it runs. I was told the carb was rebuilt. It is hard to start and smells heavily of fuel. I do notice there is fuel leaking somewhere around the carb as well. I've checked all hoses and retorqued the carb down. There doesn't seem to be any tell tale area that it is coming from. I did notice the fuel shut off switch was loose. I tightened it but still have a small mount of fuel around carb.
As far as the flooding, what else would cause it other than a faulty shut off switch? I'm wondering if that is where the fuel is coming from that I'm seeing. Is it possible that it would get out of any other part of the carb if the switch wasn't working?

Thanks!
"Once in a while you get shown the light, in the strangest of places if you look at it right."

'78 Rivi
'63 Ragtop
'73 Double cab (for sale)

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Amskeptic
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Post by Amskeptic » Mon Nov 13, 2006 8:30 am

When you say "switch" do you mean needle valve in carb? That is what I would check first. New ones are crap half the time. I would also check the float level and fuel pump output. VW originally had a cut-off valve in the top of the pump or in the fuel line to prevent percolation (a glossary term we need to add) when the engine was hot.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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MidWesty
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Post by MidWesty » Mon Nov 13, 2006 10:40 am

I was actually talking about the fuel cut off that is screwed into the left side of the carb that keeps the engine from dieseling when shut off. Not sure of the actual term. Is that what your referring to? I've rebuilt 1 carb in my life and it was a 28 on my '63 ragtop. It is running fine still to this day. I'm not real familiar with all the components included in the carb. I know some of the parts included in the rebuild kits but that's about it.
I went out and started it this morning and let it run all of 2 minutes at most and the carb was all wet when I shut it down. I talked to the PO, and the carb is actually new, not rebuilt.
Can the float be checked without pulling the carb or should I just plan on yanking it and going through the whole thing?

Thanks!
"Once in a while you get shown the light, in the strangest of places if you look at it right."

'78 Rivi
'63 Ragtop
'73 Double cab (for sale)

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Amskeptic
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Post by Amskeptic » Tue Nov 14, 2006 10:27 am

MidWesty wrote:I was actually talking about the fuel cut off that is screwed into the left side of the carb that keeps the engine from dieseling when shut off.
I talked to the PO, and the carb is actually new, not rebuilt.
Can the float be checked without pulling the carb or should I just plan on yanking it and going through the whole thing?
The electromagnetic cutoff is in no way responsible for your symptoms.

New carb makes the needle valve more suspect. Some of these neoprene needle valves will not seat when new without lots o' fuel pressure working against the float to help them develop a memory. I had a serious all-night flood when I installed new needle valves without starting the engine when I was done. Due to lack of pump pressure, the new valves dribbled all night. . . . a gallon of fuel in the oil in the morning. After an oil change, just running the car around the block cured it.

You can check the float level by idling the engine with a warm-but-not-hot engine for a minute. Shut it off and remove the top of the carburetor and measure from the fuel line to the edge of the carburetor body. I think it is 17mm with the Pict 3, and 13mm for the dual carb buses..
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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MidWesty
Getting Hooked!
Location: Where the grass is blue
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Post by MidWesty » Tue Nov 14, 2006 4:02 pm

I'll try the float test and see what it shows. I plan on changing the oil this weekend, hopefully it isn't as bad as your problem was. The engine has a little less than 500 miles on it and I don't want to take any chances. Thanks for the reply and I'll report back.

Thanks!
"Once in a while you get shown the light, in the strangest of places if you look at it right."

'78 Rivi
'63 Ragtop
'73 Double cab (for sale)

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