POKING AROUND THE ENGINE

The Lanchester L.A. 10 1935 'Sports Saloon' has a four cylinder engine which apparently generated 32 brake horsepower when new. Not exactly lively at best and 60+ years later there was a suspicion that at least half of the horses had expired or been put out to grass, so I decided to see if a 'de-coke' would rejuvenate the remaining beasts under the bonnet. The Lanchester '10' Drivers Handbook set out the order for taking things apart and having obtained a new cylinder head gasket, and replacement oil filter (these are the throw-away variety) I got started.

There were many rusted nuts and bolts needing careful attention, and often I had to use a degree of brute force (coupled with a silent prayer that nothing vital would crumble) but perhaps the most difficult bit was separating the cylinder head from the engine block and this required some judicious tapping, prising and levering.

It was disappointing after the considerable work involved not to find great mounds of carbon all over the place, and while the state of the nuts and bolts suggested that it had been some time since a previous de-coke I suspect that the car had not done excessive mileage since then. As half expected, cleaning away the carbon and re-grinding the valves did not result in very significant increase in engine power and more drastic action was obviously needed.

A full overhaul of the engine was called for - with possible conversion to using unleaded petrol - and I checked that this could be done locally, but before taking the plunge I first satisfied myself that tinkering with carburettor, coil  and distributor would not miraculously recover my lost horses at a fraction of the cost.

There was no miracle so I gritted my teeth, removed bonnet and radiator, stripped down the engine then placed myself in the (very capable) hands of my Motor Engineers for a time while they obtained/made engine parts, came and re-bored all four engine cylinders at my home, and took the cylinder head  away for refurbishment/conversion.

Because there is no pit in my garage probably the most difficult part of dismantling was lying under the car fighting to separate the big-ends from the crankshaft and withdrawing the pistons. These all had to come downwards in my Lanchester where there is barely space to get them past the crankshaft and it was a bit  like trying to solve one of those awful metal puzzles. I already knew from an earlier minor confrontation with a Daimler V8 engine that a vital prerequisite to doing this sort of thing is availability of ample surfaces, trays and boxes to lay out the myriad bits and pieces from the engine compartment in an orderly fashion. When rebuilding, components should always be replaced in their original positions (e.g. cylinder head studs, rocker arms, push rods etc.) and apart from this, unless one is taking engines apart all the time, even a washer stored out of order could give pause for the thought  - 'Now where the devil did this go?'

In putting it all back together again, replacing the pistons/big-ends was just as fiddly as removing them but eventually I looked around and couldn't spot any bits that I'd left out, which was a bit of a relief. The job was completed by resetting the valve timing, ignition timing and valve clearances - all courtesy of the instructions in my Handbook - and refilling with oil.

Finally the great day arrived; the engine started without trouble, and a short road test confirmed that engine power was noticably increased. The pace of the car will never be more than sedate but I was happy.

P.S.  The decision to have the cylinder head converted to use unleaded petrol was really a case of 'in for a penny in for a pound' and if the car engine had already been overhauled I would probably have tried a suitable additive instead, given the limited mileages likely to be covered in a mid-thirties car.

P.P.S. If you want to paint the engine block and other items in the engine compartment you'll never have a better opportunity than while all the bits are out decorating your garage (or kitchen?).