Tuesday, February 4, 2014

Nothing Simple About Tuning Up A '26 Lincoln

Back in the day I had a 1975 VW Rabbit.

Real lemon. Among it's many, many problems was a worn shaft in the distributor that made the rotor wobble as it spun. It would have cost a grundle of money to replace the shaft, money I didn't have.

So the thing wobbled, which meant the ignition points didn't stay gapped properly, which meant they tended to wear out often.

I got very good at replacing ingnition points. Fortunately they only cost a couple dollars a set. Popping the top off the distributor, taking the old points out and putting new ones in, got to be automatic. Points that should have lasted 15,000 miles, easy, rarely went more than 2,000 or 3,000, but who cared?

Distributor of the '26 Lincoln showing
one set of points.
I could gap them by sight. In an all mechanical engine, no computers, no electronics, there was enough play in the system that precision didn't matter, especially since the shaft's wobble meant precision was impossible in the first place.

Rotor of the '26 Lincoln
I thought of this as I came into the Browning-Kimball Car Museum at Union Station this morning and found Steve Sherwood standing by our 1926 Lincoln, spare tire off, hood flaps up, table full of wrenches and other tools nearby.

This Lincoln is a gem. Silent film actor Ernest Torrence was its original owner, the Browning family bought it in its original unrestored condition and it has stayed that way ever since. It's got fewer than 50,000 actual miles on the odometer, and Steve didn't think it had ever been tuned up since the Brownings bought it.

It was backfiring a bit the last time he started it, he said, so he figured it was time.

The 1926 Lincoln is a far cry from my old Rabbit. It's a V-8 with a dual carb and dual distributor. That means there's two sets of points, one on each side of the distributor, and two electrical contacts that the spinning distributor hits. You could say the car really has two engines, sitting side-by-side, taking turns firing their cylinders.

Steve has to polish the points, "and the manual says you can't use sandpaper, you have to use an oiled stone," he said, just like honing a knife blade. That means he had to take each set of points completely apart, polish the point faces, and reassemble them.


Turning over the engine so you can set the gap is no simple matter. On my old rabbit I just pushed the belt on the shaft around until the point was on top of the distributor shaft's cam. On the Lincoln, Steve had to turn the engine crank below the radiator, first opening up priming cups on each cylinder to reduce the compression. The cups are there to allow extra fuel to be added to the cylinders manually in cold weather, but also make turning over the engine a lot easier.

Once he gets the distributor all put back together he's got to set the timing, pulling up floorboards in the passenger area so he can see the mark on the flywheel. The whole thing has to be set precisely, with both sides of the engine coordinated exactly, or the engine won't work.

It's a real pain, to be honest, but Steve loves it because he loves the car and all it means for history. He will spend hours pondering the thing.

Me, I'm glad my current car doesn't need any of that. I was never much of a backyard mechanic. My old Rabbit made me one, but I was not sorry to see it go.

The current run of computer-run engines, which barely need a glance from me every 10,000 miles or so, suit me just fine.




2 comments:

  1. I remember that rabbit quite well, and the floorboard hole it developed.

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  2. More than a hole. By the end the floor had almost all been replaced with sheet metal. Amazing I didn't fall through onto the ground.

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