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Tue Jul 26, 2016 11:04 pm

Here's what I found tonight. The first pic was taken right when I took the top of the carb off. The second was taken after I had gotten the base of the carb unbolted and everything detached from the carb and the top was off the whole time (gas shouldn't be leaking). The third is trying to show how wet the gasket was. The fourth and fifth are of me holding the float in hot water.

Let me know what everyone thinks.

Wed Jul 27, 2016 1:13 am

gasket should not be wet, You know know that this is ( at least one of?) the area (the carb) where you will find the problem. Now it comes down to systematic deduction in search for leaks at the carb.
Start at the connection fuel line to carb and work your way through would be my advice.

Wed Jul 27, 2016 8:43 am

Not sure I have all the facts, but here's a theory. Looking at how low the fuel level is after you first took the top off, I wonder if the electromechanical shut off valve is stuck open, allowing fuel to drain out.

In this diagram you can see a siphon path from the bowl through the E/M valve, If your jet was stuck open it may drain down to that level. This is about where your first pic shows the level.

More images here:
http://www.thesamba.com/vw/forum/viewtopic.php?t=594790

How long had it been since it was running at the time you took that pic?

Also, if that valve gets stuck closed, it won't idle. Maybe you have a sticky E/M valve?

This is a guess, since I am not familiar with those carbs.

Wed Jul 27, 2016 8:48 am

Quote: Now it comes down to systematic deduction in search for leaks at the carb.
I blew into where the fuel line connected to the carb. Air went through the valve when it was open and stopped as soon as I closed it.
I then filled the bowl with gas and let it drain out until there was no excess draining. I put the float into the bowl with the same level of gas and then saw how much drained out from the weight of the float raising the fuel level.
From the amount of gas I left in the bowl last night and the amount of gas still in this morning, I'd say the carb itself isn't leaking. There is a little bit gone, but I'd say that could be due to evaporation.

Wed Jul 27, 2016 8:54 am

your fuel pressure is too high. It's a known thing with those pumps. You can stack gaskets, you can sheave off some of the pushrod, but the preferred fix is to replace the diaphragm spring

http://www.thesamba.com/vw/forum/viewtopic.php?t=557750&highlight=fuel+pump

Wed Jul 27, 2016 9:02 am

Quote: Not sure I have all the facts, but here's a theory. Looking at how low the fuel level is after you first took the top off, I wonder if the electromechanical shut off valve is stuck open, allowing fuel to drain out.

In this diagram you can see a siphon path from the bowl through the E/M valve, If your jet was stuck open it may drain down to that level. This is about there your first pic shows the level.

I think the bowl is on the other side of the EM valve. And when I look at mine the EM valve sits below the bottom of the bowl meaning the bowl would be empty. It could be an option, but right now I'm thinking the float may be too heavy.

Wed Jul 27, 2016 9:06 am

Quote: your fuel pressure is too high. It's a known thing with those pumps. You can stack gaskets, you can sheave off some of the pushrod, but the preferred fix is to replace the diaphragm spring
Do you mean out of the box it is too high? I found that out, but I recently was able to get it down very close to what stock was. When the pressure was high the car would die at idle because the carb was getting flooded. It no longer has that issue with the pressure fixed.

Wed Jul 27, 2016 11:01 am

Here are pictures showing the max height of the fuel with and without the float in.

Wed Jul 27, 2016 2:43 pm

Hey, no offense, but you're getting wrapped up in some details here. You say your driveway is a slight incline up, right? So tilt the carb full of fuel the same as your driveway and see if it leaks fuel on the bench. Make sure your float is installed and the bowl is at 5cm or whatever you got there. If you have to put the top on it, do it.

The idle cutoff jet is below the bowl but look at the diagram above. The path of the fuel actually leaves the bottom of the bowl through the main jet and travels up to the two jets on the passenger side of the carb. From there it drains down to the idle cutoff jet. That is supposed to stop what's happening to you. Is it functioning? Have removed it and plugged it in to see if it retracts with power and extends when off? If it is non functional fuel will drain out of the bowl and get in your cylinders when the back end of the car is downhill.

The action is known as siphoning and it will pull every bit of fuel out of your carb and fuel lines while the car sits there

Wed Jul 27, 2016 3:13 pm

Quote:
Hey, no offense, but you're getting wrapped up in some details here
No thank you. That's one of the reasons I posted here and why I'm posting as many pictures as possible. I want to make sure I'm not skipping over anything.
I'm going to weigh the float today and I will also try both suggestions today as well

Wed Jul 27, 2016 3:30 pm

The float seems to be about the right weight of 10.5 grams. The only scale I have access to is in ounces and a mechanical scale.

Wed Jul 27, 2016 9:45 pm

Quote: Have removed it and plugged it in to see if it retracts with power and extends when off?
Just got finish testing that out. The valve did nothing with the power on or when the power was turned off. I checked the wire to make sure there was power to it, and it had about 12.7 volts.
It looks like I'll be ordering a new valve. Thank you.

Quote: I wonder if the electromechanical shut off valve is stuck open, allowing fuel to drain out.
The valve didn't even work. Thanks for the advice.

Wed Jul 27, 2016 9:53 pm

I have a question though...my shut off valve is the spring type and not the one that looks like there is a jet on the end. Does it matter which one i get?
This site says mine should be the one with the jet. http://vwparts.aircooled.net/Idle-Shut-Off-Valve-30-31-30-Pict-2-058129413D-p/058-129-413d.htm

Wed Jul 27, 2016 9:56 pm

PaytonD21 wrote: I have a question though...my shut off valve is the spring type and not the one that looks like there is a jet on the end. Does it matter which one i get?
This site says mine should be the one with the jet. http://vwparts.aircooled.net/Idle-Shut-Off-Valve-30-31-30-Pict-2-058129413D-p/058-129-413d.htm

Yes! Older PICT-28 and PICT-30 carbs actually incorporated the idle jet into the E/M valve. Yours is just an on-off passageway blocker.

Glutamodo posted earlier that "the H30/31 PICT aftermarket carbs use a plunger style cutoff like on a 30PICT-3 and 34PICT-3."

The website description is wrong. Check other suppliers or the Samba classifieds (including listing a WTB for you).

Maybe?:
http://www2.cip1.com/ProductDetails.asp?ProductCode=VWC%2D056%2D129%2D412
or:
http://vwparts.aircooled.net/Idle-Shut-Off-Valve-34-3-34-4-049-129-412C-p/049-129-412c.htm
or:
http://www.ebay.com/itm/CARBURETOR-IDLE-CUT-OFF-VA...mp;vxp=mtr

Others can verify the application; I'm less familiar with the new carbs and there may be variations i don't know about.

Congrats, you are close to the solution!

Wed Jul 27, 2016 10:29 pm

Sounds like a step in the right direction. Yes, yours is the plunger type like Phil says. It is designed to shutoff the gas when you turn the key off. Prevents dieseling or running on. But it stands to reason that it is also a path for that siphoning action I described, in particular when parked uphill.

Did you happen to tilt the carburetor and check for leakage? I mean that would be the nail in the coffin so to speak.

Wed Jul 27, 2016 10:46 pm

Quote: Yes, yours is the plunger type like Phil says.
Quote: Yours is just an on-off passageway blocker.
Thank you and thank you. I'll do the tilt check in the morning. Float in lid on bowl full and see what happens.

Thu Jul 28, 2016 3:58 am

You can eliminate the cut off valve by plugging it up like I did a few years ago or you can cut off the plunger and reuse your cut off valve. There's a lot written in the search about this. I've since eliminated the horizontal spring.

Thu Jul 28, 2016 10:33 am

So after tilting the carb to the angle of where I park the carb didn't leak. I even set it on the intake to make sure the level was correct and no leaking. I had to tilt it at a pretty good angle for gas to leak. Is that normal?

Thu Jul 28, 2016 10:50 am

I'd replace the E/M plunger valve and only then see what happens. It should click and actuate, so if it doesn't, all bets are off for carb behavior. Looks like about $20 and you may be home free.

Tue Jun 15, 2021 10:11 pm

Not sure if I'm in the right place.

I've got a '71 Westie that was sitting in the bush for 25 yrs. It's now up and running , the problem I'm having is fuel in the crank case. After installing a new
stock carb. , it's been driven about 50 miles. My feeling is that the diaphragm in the pump is the source.
Bentley claims you can't access the diaphragm in these pumps so they have to be replaced. My question is : is there a procedure to bench test the pump to determine if that is the problem? I've drained the oil and puled the pump It is the original and it would be nice to keep it in service.
Any suggestions would be appreciated.