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Fuel leak

583 Views 6 Replies 4 Participants Last post by  Maryland dieselnick
I noticed a small pool of diesel under the passenger side a couple weeks ago. I checked the fuel bowl lever and all seemed fine. Drove without any issues over the last 2 weeks.

Yesterday the cab had a strong diesel smell. I noticed a ton of diesel under the wheel well on the passenger side, down the side of truck etc. I must have been dumping a good amount when driving.

Checked the fuel line under pedestal and dry. Checked fuel bowl and dry. Checked the drain tube off the fuel bowl and is wet. Not sure if fuel is coming out the drain valve or from somewhere else where the hose sits.

My fuel gauge is usually 55psi and it drops dramatically when I get on it. This morning was running around 48psi and then 20's on flat surfaces. If under load or hill, it drops into the high teens (18-19) psi.

Purchased the fuel bowl replacement parts and will replace the fuel filter tonight.

Is there another location I should be checking?
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Your passenger side steel fuel line has a leak. It goes through a sheet metal clamp that bolt to the inboard side of the head. Over time, the engine’s vibration wears a hole in it. I’ve been getting them from a vendor on Amazon. Look for the one with the rubber grommet on the tube. If you can’t find it, you can use a strip of sheet rubber like a cut up inner tube. Use it for insulation against the clamp. Use oring lube on rubber sleeves at the nuts. Tighten nuts until the stop and then add about ten pounds.
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The advantage of the blue rings is that they work a little better in super cold temps and hold up longer. The ones that came with your drain will be ok if you got the yellow Teflon coating off of the surfaces first. If your old Orings were dissolved like gum, somebody at some point used some type of alternative fuel. If it was just the yellow Teflon coating left behind, that is normal.
Your pressure drop during acceleration is about normal for a stock set up.
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