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5 things you need to know before you replace your fuel tank

5 things you need to know before you replace your fuel tank

The fuel tank is a fairly important bit of kit. Without it, you wouldn’t be going anywhere. In recent years, a lot of manufacturers have made the switch to plastic fuel tanks. Not only are they safe in a crash, they also don’t corrode and they weigh less.

Older cars, however, relied on good old metal for fuel retention, and those old tanks do fail. Ultimately, you may well need to replace it.

Changing a fuel tank is a pleasingly simple job in that there are usually no specialist tools needed. However, make no mistake, this is a big, BIG job. There will be a lot to remove, a lot to work around a lot of things to be careful of.

There is of course a degree of danger when dealing with a fuel tank, what with fuel’s propensity to ignite. This is more of a concern with spark-loving petrol rather than diesel, which needs compression and heat.

No matter your fuel type, there are five things you need to know before you tackle this big job.

01 Drain the fuel

It’s the most obvious thing in the world, but for the love god, please drain the tank completely. Do it responsibly and store it in the correct container, too. Not old jars or ice cream tubs. Most cars will have a drain plug on the bottom of the tank that you can undo. Don’t drill a hole in it – drilling metal has the potential for sparks and then you’ve the potential to be turned to human-shaped toast.

02 Do it in a well-ventilated space

Even when the tank is completely drained, it’s still going to reek of fuel. As such, changing the tank is a job to be done somewhere well ventilated, not in your integral garage with the door closed.

Fuel fumes can lead you to pass out, which could cause injury. But more than that, in the case of petrol the vapour is extremely flammable. One errant spark and it’s game over.

03 Take notes and take pictures – be organised

As we said, changing a fuel tank is a big job. You may need to drop the suspension, the driveshaft might need to come out, you have to unclip all the fuel lines, the list goes on.

You’re going to have a million different nuts and bolts off the car, so do yourself a favour and bag them up and write on the bag what they’re for.

Take pictures of things being before you take them off so you know how and where they should go. You’ll be glad you did.

04 Don’t cheap out on the fittings

04 Don’t cheap out on the fittings

Are the breather lines looking rough? Have the fuel line clips corroded? What about the fuel tank straps and the bolts, have they rusted? Don’t put them back on the car then.

Rust loves a bit of osmosis, so if you put rusty bits tight against the new tank’s metal, you’re inviting it in.

As for the other parts – this is your fuel system, not only is it important, it’s also extremely dangerous. Do you really want to use knackered old bits and then just hope for the best? You’ve got the car apart anyway, so get new gear on there.

05 Have a fire extinguisher

05 Have a fire extinguisher

Sorry if we sound like a broken record, but fuel by its very nature is flammable and it takes very little to ignite it, especially in the case of petrol.

So please spend a few quid and have a fire extinguisher to hand. And we mean that. Don’t have it under the stairs in a cupboard. Have it next to you. It will stop a moment of panic from becoming a car-destroying inferno.