Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 15, 2025 ...

Fuel Tank Pressure ?

June 25, 2014, 08:36:57 pm

Is it normal to have a slight amount of pressure in the diesel tank ?
Not a lot , won't blow the cap out of your hand or anything, just enough you can hear the pressure escaping . ( after you have been driving in 90 degree weather )
I 'assumed' the tank has a vent line some where, I know what 'assuming' can do.
Thanks.............~JL~

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Re: Fuel Tank Pressure ?

Reply #1 – June 25, 2014, 08:44:13 pm

John, I know when I open our cap both in the 88 and the u280 little pressure.

Especially when it is warmer

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Re: Fuel Tank Pressure ?

Reply #2 – June 25, 2014, 09:02:32 pm

Our '93 U300 builds a moderate amount of pressure in the tank. Would think it's two or three PSI.

Pierce

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Re: Fuel Tank Pressure ?

Reply #3 – June 25, 2014, 09:21:12 pm

Thanks guys,  I was afraid I had a vent stopped up.  I knew there was not a vent in the cap. Have only owned the FT for about a year,  still learning. .............~JL~.....

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Re: Fuel Tank Pressure ?

Reply #4 – June 25, 2014, 11:36:49 pm

I don't think our tank builds any pressure. We do have a vent that I think is center forward, with a hose from top hanging down.

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Re: Fuel Tank Pressure ?

Reply #5 – June 26, 2014, 06:34:24 am

There should be no pressure in the tank. The vent hose could be kinked or plugged.

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Re: Fuel Tank Pressure ?

Reply #6 – June 26, 2014, 07:55:54 am

I have a little pressure in mine when I take the cap off...like someone else said, not much but just enough to hear.

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Re: Fuel Tank Pressure ?

Reply #7 – June 26, 2014, 08:01:55 am

I don't have a Foretravel yet but I know all GM diesel pickups pressurize the tank to 3PSI while in operation. Neither my MCI nor the Bluebird does.

TOM

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Re: Fuel Tank Pressure ?

Reply #8 – June 26, 2014, 09:34:14 am

My tank builds up a bit of pressure, I thought it was "normal".

Roland

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Re: Fuel Tank Pressure ?

Reply #9 – June 26, 2014, 08:28:39 pm

I always open the fuel tank slowly just in case there is pressure and there usually is.

see ya
ken

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Re: Fuel Tank Pressure ?

Reply #10 – June 27, 2014, 01:49:00 pm

I believe that our 3208T has a recirc. line back to the fuel tank from the injector pump and that is the source of pressure in the tank.  If your set-up is designed that way, then you will have pressure in the fuel tank.  Do all engine set-ups have this??  You might check it out and see what you have and verify that it is as it is supposed to be.  Have a great day  ----  Fritz

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Re: Fuel Tank Pressure ?

Reply #11 – June 27, 2014, 02:01:45 pm

All diesels and gasoline cars with fuel injection have a return line to the tank. Diesels only use a small percentage of the fuel and return the rest back to the tank. Gets rid of some heat that way too.

Pierce

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