vapor lock shooting gas out

today i was going to take a look at a 87 560sec amg and i made a left turn and this car comes up beside me and tells me i just lost a bunch of gas on the turn. i went to the mechanic and tried to call his home but he wasnt there. there was a hoes by the back right wheel that was shutting it our after spending a hour figuring it cam from the gas fill i had no idea WHAT TO DO. a tow truck wich is sad to say new me stoped and told me i had vapor lock and i need a new gas cap. well the mechanic has some scrap cars one a 1982 sel. so i grabed the cap and it went away what caused this and what can i do to prevent it.

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Dan Younes
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1985 euro 500sel 223k
1986 420sel 86k soon 2 be
1981 300sd 278k sold
1979 240d 298k sold
1983 300sd 272k sold
1989 chrysler 2.2l Turbo
Leabaron 140k
1989 Dodge Carvan Se 295k
1994 S500
(hopefully someday)

[Benzmac]

All Mercedes have a drain to let the fuel run out in the event of an overfill. I think that you may have had a bad cap and you topped off the fuel...The excess had to go somehwere.

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Benzmac:
Donnie Drummonds
1991 GMC Syclone
ASE CERTIFIED MASTER AUTO TECHNICIAN
SERVICE MANAGER FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
PARTNER IN MERCEDESSHOP.COM

ya i did top off the night before and when i got in i knew i smelled premium gas. this is the 7th gas cap i have gone thru this one i got off the 1982 seems to be a lot stronger. does the part shop sell the metal gas caps. thank you

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Dan Younes
---------------
1985 euro 500sel 223k
1986 420sel 86k soon 2 be
1981 300sd 278k sold
1979 240d 298k sold
1983 300sd 272k sold
1989 chrysler 2.2l Turbo
Leabaron 140k
1989 Dodge Carvan Se 295k
1994 S500
(hopefully someday)