1975 Ford Landau Pricing and Specs

Converting big, thirsty vehicles like the F100 to run on LPG was a pretty common thing a few years ago. Then the pump prices of LPG and petrol become close enough that there wasn’t really the cost advantage to be had with an LPG conversion. Couple that with the cessation of local car production (which also spawned a few factory LPG cars) and suddenly, LPG had disappeared into the shadows a little.

It shouldn’t have, as LPG is plentiful in Australia and could have been our alternative to diesel had the industry been developed correctly, the advantages marketed properly and the Federal Government taken a less than greedy view of selling the stuff overseas cheaply while taxing it heavily here. Meantime, anybody who bought a diesel instead for the running costs must be looing at diesel prices now and be wondering if they made the right call.

Anyway, the vast majority of these LPG conversions were to what’s called dual fuel. That is, the vehicle can run on LPG or, at the flick of a switch, on normal unleaded. But some cars were converted to be dedicated LPG runners and couldn’t use ULP at all, which I’m assuming is what you have.

This makes the car less attractive to some buyers, but as fuel prices creep upwards, maybe the allure of LPG will make a comeback. Certainly a big, heavy truck like an F100 has more to gain by running on LPG than a smaller, lighter vehicle.

It is possible to convert the F100 back to run on petrol, but you’ll need to find all the original fuel system components including a tank, fuel pump, lines, filters and the appropriate carburettor. Then you need to decide whether to leave the LPG tank in place and convert to a dual fuel set-up, or ditch the LPG altogether for ULP-only running. Either way, you could be up for a couple of thousand dollars or more by the time you’re done. Which then begs the question whether that will then add the same amount to the vehicle’s asking price.

A modern car like the Ranger has a heap of sensors that warn the on-board computer of something that’s getting too hot, causing the car to enter limp home mode to avoid further damaging itself. That means you could be looking at a problem as varied as the condition of the radiator and its plumbing, the intercooler, coolant pump, the EGR valve and more. Perhaps it’s a simple case of low coolant triggering the limp home. Certainly, these engines can lose coolant if the EGR valve is damaged or leaking.

But then you can also move along to the driveline, because a too-hot transmission will also trigger a limp-home situation. Is the transmission cooler working properly? Does the transmission have the correct quantity of fluid in it?

Start with the basics and don’t be afraid to give the car an electronic scan as the fault codes it has logged could be a big clue in what component is causing the grief.

I'd say you're looking at two different problems here, neither one of which involves the actual fuel tank (which is, indeed, 55 litres). The first problem is more likely to be the calibration of your fuel gauge that is out. If the gauge isn't reading accurately, it will tell you the tank is emptier (or fuller) than it really is. Your car is actually doing what most fuel gauges do, which is to be a bit pessimistic, suggesting there's not as much fuel still in the tank as there really is. You could have the gauge recalibrated, or simply know that even when the needle is at empty, you've still got a buffer zone of fuel remaining.

The fuel consumption, meanwhile, is another issue and it's true to say that 20 litres for 140km of driving is too thirsty. A basic tune up might help, starting with fuel filters, air cleaners and spark plugs. But don't ignore things like correct tyres pressures and whether there's a roof rack fitted; these things will affect fuel economy more than you might imagine. And never under-estimate the affect driving style has on fuel use. A driver who smashes the throttle from every green light will soon start using more fuel every kilometre.