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Reply To: Ford Lehman fuel consumption

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David Babsky

Our 1989(?) Ford Lehman uses about 5 litres an hour at 1600rpm, giving us a constant 7 knots. Unlike Rose-Anne – above – we never seem to burn any oil! (But I do keep several spare gallon cans of engine oil and gearbox oil – different substances! – down beside the engine ..just in case! AND spare fan belts. And make sure that you know the correct mark for the engine oil level on your dipstick!)

Regarding the “..spare relay, the one that ensures both steering positions are in neutral before you can start the engine..” I think this means (well, it does on ours, anyway) the elaborate metal ‘skeleton’ arrangement of sliding metal plates, down beside the front-left of the engine, into which the ‘Morse’ or ‘Teleflex’ cables run from the throttle / gearstick lever. As Rose-Anne mentions, BOTH (internal and outdoor ‘poop-deck’) gear levers need to be in the central ‘neutral’ position before the engine can be started. But perhaps Rose-Anne means a separate small electrical relay box which is connected to that metal skeleton, and which also connects to the boat’s starter switch: I don’t know about that, as we’ve never had any trouble with ours, and I’ve never even thought about there being one till just now!

Dip the gearbox (there’s a built in awkward-to-reach extractable dip stick) to make sure that it’s full up to the mark, and if you see any white ‘margarine’ in there, that means that water’s leaking into the gearbox via a cracked gearbox oil cooler (strapped onto the rear of the engine: one’s a roller for the engine oil; one’s a cooler for the gearbox oil).

If the engine hasn’t been run for a while, ‘prime’ the fuel pump by squeezing the rubber cover on the fuel pump, which is about three-quarters the way back from the front of the motor on the right-hand side. That assumes that you’ve first turned ON the fuel ..on ours, it’s with a three way tap under the steps down to the back cabin: centre position OFF, left position PORT tank, right position STARBOARD tank (or is it the other way round?) ..anyway: centre OFF; one way or the other, one or the other tank.

If the engine hasn’t been run for a while – or even if it has – check (and maintain spares of) the FUEL FILTERS! Very important. On a rough passage, if the boat’s been standing for months, there’ll likely be messy deposits in the bottoms of the tanks, which will get stirred up as the vessel rolls and pitches, and can then clog the fuel filters. Replace the filter elements in the main fuel pipe AND in the filters attached to the engine.

If you can reach them, open the small taps at the bottom of each tank FIRST, to drain off any sludge from the bottom of the tanks, and add ‘Marine 16’ diesel-bug killer (available from most chandleries) to both tanks.

If the boat hasn’t been used for a while, DO A SHORT SHAKEDOWN JOURNEY FIRST before going from Ireland to Portugal, to find out what doesn’t work, and what’s just about to fail. Check that the anchor chain really is fastened to the boat! Carry seacock bungs, a WORKING radio, and be sure that the fuel gauges are ACCURATE! (I replaced ours – the mechanisms in the tanks – as the originals were (invisibly) cracked and showed false readings on the wheelhouse dials.) When the gauges show that two thirds has been used ..i.e; there’s a third of a tank left.. REFUEL as soon as poss, because ‘one third left’ in a flat calm sea can mean that the fuel pump sucks just air when the boat is heeling!

And when the boat is heeling (over to port, I think) the seawater inlet may be out of the water(!) so if you’re motor-sailing and heeled over, do make sure that cooling water is still coming out of the starboard ‘tell-tale’ pipe and the rear exhaust pipe!

All the best!