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300SD Fuel Tank vent question

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familydieseldr's picture
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When I remove the fuel tank cap on my 1985 300SD, a blast of compressed air
escapes/ or possibly it is a vacuum rushing in, I can't tell.

I just replaced the leaking fuel line from the strainer, so possibly
the pressure/vacuum was previously venting via the leak.

The new fuel line does not leak, and I now have this pressure/vacuum in the tank.

There must be a vent somewhere, but I looked at the cap and can't see any
vent hole in it.
Is there separate vent plumbing, where is it?
Can it be cleaned out or do I replace it?
Thanks
Familydieseldr

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__________________
1983 300TD = old clacker 370,000-retired parts donor
1985 300SD = Son's Diesel cruiser 332,000
1985 300TD = Dad's Diesel wagon 183,000
1992 Kubota Diesel tractor = mutant lawn mower 390hrs
2000 Ford Powerstroke Diesel = Wife's Toyota crusher 253,000
2004 Chevy Blazer = Daughters gas SUV 80,000
2010 BMW 335d = new clacker toy 56,000
Anonymous
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My old 300 Sd had mud in the vent line. Run a wire through it. There is a flare right behind the rear drivers wheel where it comes out. Remove it and the pressure regulator near the fuel tank and clean the stuff out.

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familydieseldr's picture
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Thanks for the good advice!
Would I look for the regulator from under the car, where the fuel line plumbing is located?
Or is it accessed through removal of the back seat or through the trunk?
Familydieseldr

__________________
1983 300TD = old clacker 370,000-retired parts donor
1985 300SD = Son's Diesel cruiser 332,000
1985 300TD = Dad's Diesel wagon 183,000
1992 Kubota Diesel tractor = mutant lawn mower 390hrs
2000 Ford Powerstroke Diesel = Wife's Toyota crusher 253,000
2004 Chevy Blazer = Daughters gas SUV 80,000
2010 BMW 335d = new clacker toy 56,000

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