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Discussion Starter #1
My patrol is leaking fuel out of the fuel cap. From what ive been told its the breather that is blocked. Whats the easiest way to get to the breather. Do i need to pull the fuel tank out? Its a lwb wagon if that helps.

TIA
 

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Rust is just natural weight reduction.
1986 SD33T SWB
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The breather hose runs along the top of the tank and through a check valve.
You will need to remove the tank as the breather hose is held to the tank with little plastic clips.
 

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Discussion Starter #3
Well thats a pain in the ass. Is there anything i need to know about pulling the tank out? Is it pretty straight forward job to do?
 

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My patrol is leaking fuel out of the fuel cap. From what ive been told its the breather that is blocked. Whats the easiest way to get to the breather. Do i need to pull the fuel tank out? Its a lwb wagon if that helps.

TIA
That doesn't make sense, the breather is above the liquid level. Does it only happen on hot days with full tanks ?
 

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Discussion Starter #5
Happens all the time it doesnt matter how fuel is in the tank.
From what i have been told its common for the breather to get blocked and then the pressure builds up and pushes the fuel out the cap.
Im happy to b corrected if im wrong but if a blocked breather isnt the answer. Then can some one tell me why the fuel is leaking out the cap. And i have replaced the fuel cap and it continues to leak out of it
 

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As discussed above the breather is above the tank and difficult to get to. It is held on by a clip and generally breathes into the chassis rail. You can get to it and drag it down to check the valve but may break the plastic fittings trying.

I had a blocked breather up the cape once and the result was that I ran out of fuel even though the fuel guage was still reading 1/3 full. If your fuel cap is sealing and you get a blocked breather, the result is that the engine creates a suction in the tank. If you still have a stock 82L tank, it will cause the bottom of the tank to cavitate upward, as happened to me. This was caused by a blocked breather inside the chassis rail. I cleared the blockage without removing the tank, but the clips suffered.

The downside is that when this happens in a stock tank, the fuel pickup bends upward as well and doesn't return to its original pick-up position when the vaccuum is removed. The bottom of the tank will return to its original position, but means that until the fuel pickup pipe is repaired, you will continue to run out of fuel when there is plenty of fuel in the tank. The only way to fix it is to remove tank + fuel. Its not difficult, but is a pain!:headwall:

If the breather check valve is not working, fuel will flow into your chassis rail when you fill right up. Good rustproofing if your using diesel!:D

It sounds like your fuel cap may just need a new nitrile rubber seal. Just go to a rubber supply shop and they will probably cut a new one for you. Also check the fuel filler hose is fitted correctly and the hose clamps are tight.
 

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Rust is just natural weight reduction.
1986 SD33T SWB
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I pulled my tank last weekend... As Shorty said its not hard but it is a real pain, particularly the hose connections to the tank. Would be easier with a body lift.
 

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Discussion Starter #8
Ive replaced the cap i dropped the tank the other day. Un blocked the valve so far no fuel leaking out of the cap
 

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Discussion Starter #9
Thanks for ur help guys. Hopfully the problem is fixed only time will tell.
I did it at work on the wheel aligning hoist which made the job abit easier and quicker.
But i did snap to bolts when i was undoing the strap that goes under the tank
 

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Rust is just natural weight reduction.
1986 SD33T SWB
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That strap isn't necessary anyway if you have a rear wheel carrier, I believe it's part of the underside wheel carrier, as I have only seen it on models that originally had the tyre underneath.
 

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Discussion Starter #11
Thats good to know. When i 1st brought it it had the wheel underneath untill i got hung up on it.
Thanks James
 

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Fuel tank breather pipe ends on the RH chasis rail under front wing. Try to blow some air through it with fuel tan cap open. I've lenghtened mine so it ends just under bonnet level - usefull with deep water crossings.
;)
 
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