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How to rotate the engine

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eejay56

eejay56

Jedi Warrior
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Is there a secret trick rotate the engine for adjusting valves, points on a Spit? I have been putting it in 4th and rolling it back and forth but that's a pain. I miss the VWs where you just put a wrench on the crank pulley. I guess that could work with a socket. Anybody know what size the crank pulley nut is?
 
1 and 13/16" on a later Spitfire...if there's enough room for the socket without pulling the radiator!

Pull out the spark plugs, and the engine will be easier to turn over however you choose to do it! (Without plugs in, you'll likely be able to tug on the fan belt.)
 
With the plugs out and the fan belt at proper tension, you should be able to put a socket/wrench on the alternator fan nut and turn the engine over with that.
 
eejay56 said:
...adjusting valves, points... I have been putting it in 4th and rolling it back and forth...
Click to expand...

FWIW -- on some engines you only want to move the engine forward as you come up to the spot where the points open. If you miss it you can back up a good ways then try again to hit the spot whilst moving it forward.

Otherwise, I would think the rolling method would be pretty easy on a Spit since the front tire is right there. Of course it's much easier to move the car by pushing the top of the tire rather pushing the chassis since the tire top gives you a (2:1?) mechanical advantage.
 
right on Geo,thats how I do it,altho I'm to stupid to figure out the math part of it....how DO you figure out the math part?
 
I'm no mathematician either, but when I push the top of the tire forward 1" the car also moves 1"... so my hand goes forward 2". Sounded like a 2:1 deal to me.

P.S. I was under the impression there would be no math on this portion of the test.
 
The mechanical advantage of having the car in gear and rolling the tire is dependant on what gear you're in, the differential ratio and the size of the tire.

Enough math to make your head spin. /bcforum/images/%%GRAEMLIN_URL%%/crazyeyes.gif
 
That's just the coriolis effect kicking in
 
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