Need tips for draining fuel tank, straining gas, and protective tank maintenance. (1 Viewer)

[SiestaTom]

Would appreciate any tips and advice. 1974 FJ40
I’m going to remove and eliminate a broken electric fuel pump that feeds into my mechanical pump, which is also broken and will be replaced with OEM part. I figure I might as well drain the fuel tank and see if there is any debris before hooking everything back up. I have no reason to believe my fuel is contaminated but with a rig this old, it would not be surprising to have some crud in the bottom of the tank. And best I can tell the tank is not leaking.

I estimate I’ll have 5 gallons to drain and re-use. Should I filter this before putting back in tank? How can I filter this? Would a couple of coffee filters in a funnel work?

Also, when I have the tank empty, is there some preventive maintenance that would make sense? Given the condition of the tank, and to limit the scope of the job, I’m not inclined to remove it.

I don’t know the original fuel line design but it appears I have flexible lines going from the tank to the electric pump. The output from that pump connects with a short rubber line to a hard fuel line which goes to the engine compartment and the newly replaced fuel filter.

 

[KRGfab]

Honestly, unless you plan on pulling the tank, there isn't a whole lot you can do to it, besides doing a visual inspection. With the old gas you can filter any solids out of it with either a fine mesh strainer or coffee filters could work too. On my 72 it goes rubber line from tank to frame mounted hard line, then rubber line to fuel filter, then rubber again to mechanical fuel pump then a hard line to the carb.

 

[reddingcruiser]

^^2x. You can use a small inspection mirror through the gauge sending unit hole to look around, and see what's sitting in the well, the tank baffles will preclude seeing much else.

FJ40 gas tanks often develop leaks caused by rust originating from the exterior, often from moisture accumulating in debris under the tank or the pads the tank sits on. IMHO, the best preventative maintenance is to check the underside of the tank for rust pitting. I'll concede that pulling the tank is a PITA, but if you are going to drain it and disconnect the plumbing, now might be the time. However, you know your Cruiser and can make a judgement based on it's history and overall condition.

Good luck.

 

[kerplunk]

You might want to consider just putting a clear plastic inline filter (i.e. wix 3302) between the tank and the pump and see what it collects.

 

[Mark Jennings]

Would appreciate any tips and advice. 1974 FJ40
I’m going to remove and eliminate a broken electric fuel pump that feeds into my mechanical pump, which is also broken and will be replaced with OEM part. I figure I might as well drain the fuel tank and see if there is any debris before hooking everything back up. I have no reason to believe my fuel is contaminated but with a rig this old, it would not be surprising to have some crud in the bottom of the tank. And best I can tell the tank is not leaking.

I estimate I’ll have 5 gallons to drain and re-use. Should I filter this before putting back in tank? How can I filter this? Would a couple of coffee filters in a funnel work?

Also, when I have the tank empty, is there some preventive maintenance that would make sense? Given the condition of the tank, and to limit the scope of the job, I’m not inclined to remove it.

I don’t know the original fuel line design but it appears I have flexible lines going from the tank to the electric pump. The output from that pump connects with a short rubber line to a hard fuel line which goes to the engine compartment and the newly replaced fuel filter.

I used a paint strainer, a funnel and a homer bucket and drained through the drain plug at the bottom of the tank. You could use an inspection mirror but I don’t think you’ll need one. If you remove the tank float, it’s a pretty good size hole and you can see pretty clearly the tank bottom. Just make sure the aluminized coating is still in tack and that’s it.

Since the in-tank fuel pick up is just above the bottom of the tank, water can collect in the tank sump....and that’s where you’ll see rust if there is any. And that’s what you’re looking for.

 

[kerplunk]

I used a paint strainer, a funnel and a homer bucket and drained through the drain plug at the bottom of the tank. You could use an inspection mirror but I don’t think you’ll need one. If you remove the tank float, it’s a pretty good size hole and you can see pretty clearly the tank bottom. Just make sure the aluminized coating is still in tack and that’s it.

Since the in-tank fuel pick up is just above the bottom of the tank, water can collect in the tank sump....and that’s where you’ll see rust if there is any. And that’s what you’re looking for.

I've dumped 5 gallon paint buckets before without a problem... But gasoline can eat some plastics. If you're going to dump it, the safest thing to dump it into is a gas can.

And the safety class manual told us that once you put gas into the 5 gallon bucket, it will always have fumes from that gas remaining... And possibly be explosive.

 

[SiestaTom]

Thanks everyone. Some great suggestions. I drained the tank thru the disconnected fuel line hose and a small amount of particles came out at the end which didn’t seem bad. I may try and pull the sending unit and do a mirror inspection. And the tip about corrosion starting from the exterior tank bottom is golden. The tank had more than my 5 gallon can could hold (stupid miscalculation) and I did get some run off while draining, and lots of fumes. I was a bit freaked but my garage has good ventilation and I had two fires extinguishers at the ready. But what really freaked me was later, when the worst of the fumes had cleared, I was trying to remove one of those spring clamps from a fuel hose with pliers, and when it slipped, it created a spark! That sobered me up fast and I vowed no more work until the gas had fully evaporated. I think my guardian angel was watching over me. Whew.