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TDC Question

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mrv8q

mrv8q

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So in the midst of pulling my oil pan to replace the gasket, (which has become so brittle that it doesn't apparently seal anymore), inspiration hit me: I can easily see TDC from underneath, by rotating the crank and observing the piston:
IMG_1334.jpg


However, I'm finding it impossible to have the crank turn while the car is in gear, which is how I thought it would work: raise car, place car in 4th, pull sparkplugs, turn rear wheels, observe rotation of crank, watch for TDC. 1st, 4th, or reverse, no crank turning. Am I wrong in my theory of wheel turning = crank turning, and is this whole idea hare-brained? I think it would be tough to get a wrench and rotate the crank from the front; the radiator is too close to my TR6 yellow fan...
 
The differential is defeating you. You turn a rear wheel. The opposite rear wheel turns in the other direction while the crank remains stationary (energy following the path of least resistance). You need to immobilize the wheel not being turned -- or turn both wheels at the same time.
 
It's really tough to turn the engine from the rear wheels anyway, because of the gear ratio in the differential. With the pan off, it's easier to just grab the crank and turn it (which may still be difficult, depending on how stiff your engine is).

With the stock fan, you could just grab a fan blade and turn that; but you don't want to do that with the plastic fan.

Frankly seems a little hair-brained to me anyway. Why do you want to see TDC?
 
Why don't you just turn the starting handle?
 
Filled in radiator.... anyway, back to buttoning it up.
 
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