Gas in oil

Carbs & F.I.

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THall
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Location: Verona, Wisconsin
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Gas in oil

Post by THall » Tue Mar 13, 2012 12:14 pm

'78 Westy with dual Webers and electric fuel pump.

So, my bus is currently still in hibernation mode in my garage, but when I went outside the other day I could smell fuel and noticed the cardboard under the bus was soaked with oil/gas combo. It appears to have leaked out of the inspection plate (taco plate?) So I drained the case and sure enough it was very thin and definitely contaminated with gas. What are some possibilities that would cause the fuel to get into the case while not being run? I haven't had a chance yet to poke around for clues, was hoping to get some guidance on what to look for.

Thanks,

-Tim
'78 Westy 2.0 FI

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Amskeptic
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Re: Gas in oil

Post by Amskeptic » Tue Mar 13, 2012 3:54 pm

THall wrote:'78 Westy with dual Webers and electric fuel pump.

So, my bus is currently still in hibernation mode in my garage, but when I went outside the other day I could smell fuel and noticed the cardboard under the bus was soaked with oil/gas combo. It appears to have leaked out of the inspection plate (taco plate?) So I drained the case and sure enough it was very thin and definitely contaminated with gas. What are some possibilities that would cause the fuel to get into the case while not being run? I haven't had a chance yet to poke around for clues, was hoping to get some guidance on what to look for.

Thanks,

-Tim
Needle valve seat leak. Blame the Webers. Neoprene needle valves need pressure to maintain their seal. All winter may have been enough time for the bowls to evaporate a bit and let the needles relax.
Try running the fuel pump to build up pressure and look into the throats with a mirror and flashlight [or cold trouble light (flourescent which sucks but does not explode) ] to see if any fuel dribbles or drips. Tap carbs at fuel inlets when pump is running.
Colin
(how's it going over there in immaculate garage land?)
BobD - 1978 Bus . . . . . . . . . . .111,130 miles
Chloe - 1970 bus . . . . . . . . . . . 206,787 miles
Naranja - 1977 Westfalia . . . . . 94,615 miles
Pluck - 1973 Squareback . . . . . 55,510 miles
Alexus - 1991 Lexus LS400 . . . 72,990 miles

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THall
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Location: Verona, Wisconsin
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Re: Gas in oil

Post by THall » Wed Mar 14, 2012 7:57 am

Amskeptic wrote:
THall wrote:'78 Westy with dual Webers and electric fuel pump.

So, my bus is currently still in hibernation mode in my garage, but when I went outside the other day I could smell fuel and noticed the cardboard under the bus was soaked with oil/gas combo. It appears to have leaked out of the inspection plate (taco plate?) So I drained the case and sure enough it was very thin and definitely contaminated with gas. What are some possibilities that would cause the fuel to get into the case while not being run? I haven't had a chance yet to poke around for clues, was hoping to get some guidance on what to look for.

Thanks,

-Tim
Needle valve seat leak. Blame the Webers. Neoprene needle valves need pressure to maintain their seal. All winter may have been enough time for the bowls to evaporate a bit and let the needles relax.
Try running the fuel pump to build up pressure and look into the throats with a mirror and flashlight [or cold trouble light (flourescent which sucks but does not explode) ] to see if any fuel dribbles or drips. Tap carbs at fuel inlets when pump is running.
Colin
(how's it going over there in immaculate garage land?)
Thanks Colin! I will take a look this weekend and see what I find. Do you think I need to replace the O-ring that seals the inspection cover where it leaked?

All's well in immaculate garage land despite the leak. Fortunately the cardboard took the brunt of the puddle, so not too big of a mess. Yeah, I'm pretty anal about things being clean and tidy.

Gonna be 77 and sunny in the Madison area today, really makes me want to get the bus out....crazy for March in Wisconsin.
'78 Westy 2.0 FI

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dtrumbo
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Re: Gas in oil

Post by dtrumbo » Wed Mar 14, 2012 8:07 am

THall wrote:Do you think I need to replace the O-ring that seals the inspection cover where it leaked?
I don't know if you specifically addressed the question to Colin, but I'll toss my two in. I'd replace it. Apparently it might have stopped oil from leaking, but when thinned with gasoline it seeped past. In a way this turned out to be a good thing since it prompted your discovery of having gas in your oil. Not a good thing. That said, it's easy to replace since you've got to drain and change the oil anyway.

Item 'O' in the following link.
http://www.bus-boys.com/oilsump7283.html
- Dick

1970 Transporter. 2015cc, dual Weber IDF 40's
1978 Riviera Camper. Bone stock GE 2.0L F.I.
1979 Super Beetle convertible.

... as it turns out, it was the coil!

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THall
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Re: Gas in oil

Post by THall » Wed Mar 14, 2012 10:37 am

dtrumbo wrote:
THall wrote:Do you think I need to replace the O-ring that seals the inspection cover where it leaked?
I don't know if you specifically addressed the question to Colin, but I'll toss my two in. I'd replace it. Apparently it might have stopped oil from leaking, but when thinned with gasoline it seeped past. In a way this turned out to be a good thing since it prompted your discovery of having gas in your oil. Not a good thing. That said, it's easy to replace since you've got to drain and change the oil anyway.

Item 'O' in the following link.
http://www.bus-boys.com/oilsump7283.html
Thanks Dick,

Agreed, it would seem foolish to not replace it at this point. And yes, perhaps the leak was a blessing in disguise. Wouldn't have wanted to start it in that condition.
'78 Westy 2.0 FI

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SlowLane
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Re: Gas in oil

Post by SlowLane » Wed Mar 14, 2012 8:36 pm

I'm sure that this will garner a bit of criticism, but "back in the day", when I was running a Corvair-powered '71, among the many, ahem, improvements I made to the bus was tapping a fuel shutoff valve similar to this one into the fuel tank bung. Was really nice to be able to shut off the fuel at the source before performing work on the engine, which it seemed to require about every other weekend.

Part of the problem here is the fact that the bay window fuel tank is at a higher altitude than the engine, which is nice as far as reliable fuel delivery goes (the pump doesn't have to suck fuel up hill), but not so nice if any part of your fuel system that is supposed to prevent siphoning doesn't do its job.

The Vanagon, on the other hand, has the fuel tank at about the same altitude as the engine, so siphoning isn't an issue (unless you live in the wrong nieghborhood. Different topic).
'81 Canadian Westfalia (2.0L, manual), now Californiated

"Wisdom comes from experience. Experience is often a result of lack of wisdom."
- Terry Pratchett

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THall
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Re: Gas in oil

Post by THall » Mon Nov 05, 2012 5:55 pm

So this problem seemed to have rectified itself during the summer months when it was being driven often, but now after it's been sitting for the last month I'm noticing an oil drip/leak similar to what I found over last winter. I will have the carbs taken apart and fixed in the spring. My question is what's the best way to keep the fuel from continuing to seep into the crankcase until spring? Pinch off the fuel line? I imagine the engine should also be run to burn the fuel currently in the carbs? Thank you for the help!
'78 Westy 2.0 FI

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Amskeptic
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Re: Gas in oil

Post by Amskeptic » Mon Nov 05, 2012 8:27 pm

THall wrote:So this problem seemed to have rectified itself during the summer months when it was being driven often, but now after it's been sitting for the last month I'm noticing an oil drip/leak similar to what I found over last winter. I will have the carbs taken apart and fixed in the spring. My question is what's the best way to keep the fuel from continuing to seep into the crankcase until spring? Pinch off the fuel line? I imagine the engine should also be run to burn the fuel currently in the carbs? Thank you for the help!
I explained it years ago, up the thread. So yes, block the fuel supply. Preferably a small phillips screwdriver blade up the inside of the hose about an inch and a half, with a fuel hose clamp. Do not actually squeeze the hose with a hose block-off clamp or visegrips all winter. I have let fuel sit in the Solex bowls all upstate New York winter year after year with no ill effects, but who knows if Webers give the float bowls too much atmosphere which makes gas go bad.
Colin
BobD - 1978 Bus . . . . . . . . . . .111,130 miles
Chloe - 1970 bus . . . . . . . . . . . 206,787 miles
Naranja - 1977 Westfalia . . . . . 94,615 miles
Pluck - 1973 Squareback . . . . . 55,510 miles
Alexus - 1991 Lexus LS400 . . . 72,990 miles

72Hardtop
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Location: Seattle, WA./HB. Ca./Shizuoka, Japan
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Re: Gas in oil

Post by 72Hardtop » Tue Feb 12, 2013 1:50 am

This shouldn't be an issue while the vehicle is not running. Webers are cosidered an open air carb. Letting them sit for a length of time will allow for the fuel to evaporate in the bowels. But without any pressure in the line (not running) they should not be getting fed any fuel.

1...In a bus ran with a mechanical pump the fuel would have to pass thru the fuel pump then travel up thru the tin and then onto the carb/s. Even with a full tank that's not likely to happen. The fuel pump should not allow for travel of fuel thru the pump when not running.

2...Now with an electric pump most are secured up high near the tank so the fuel would not likely need to travel in an upward direction after leaving the tank. It travels directly to the carb/s. The fuel pump itself when off should not allow for thr travel of fuel thru the pump when not running.

The Weber fuel inlet needles should be made of Viton material. Webers would either need pressure or a vaccum to pull fuel thru the carb neither of which should be occuring with the bus off. The OP must have sort of pressure building that's pushing the needle/s off their seat/s when the vehicle is off. Or the issue is occuring while the bus is running and he is just not aware of it.
1972 Westy
2056cc T-4 - 7.8:1 CR
Weber 40mm Duals - 47.5idles, 125mains, F11 tubes, 200 Air corr., 28mm Vents
96mm AA Biral P/C's w/Hastings rings
42x36mm Heads (AMC- Headflow Masters) w/Porsche swivel adjusters
71mm Stroke
Web Cam 73 w/matched Web lifters
S&S 4-1 exhaust w/Walker 17862 quiet-pack
Bosch SVDA w/Pertronix module & flamethrower 40K coil (7* initial 28* total @3200+)
NGK B5ES @ .028
002 Trans
Hankook 185R14's

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