QuestionI just purchased a '75 Spit and want to adjust the valves. Other than using a remote starter, how do I rotate the shaft? In neutral the alternator belt or air pump belt won't turn. I jacked up the rear end, put trans in neutral, still can't turn shaft. Tried it in all other gears with rear end off the floor. No luck.
AnswerMost of us will use a 1 13/16 socket and a 3/4 ratchet or breaker bar to spin the crank.
If you have a slanted radiator and limited clearance, you can use a humongous 18" crescent wrench, as the crank nut on a 1500 slightly protrudes the pulley.
Since following the rules of nines when adjusting valves requires you to watch the rocker position at its maximum lift, any other method doesn't have enough refinement or doesn't allow you to see the rocker position as you are spinning the crank.
You always want to spin the crank clockwise to keep the camshaft in tension; don't spin counter-clockwise if you over-shoot; keep going clockwise to the next valve setting and eventually come back to the valve you overshot.
Taking out the spark plugs, if you haven't already, will help with the spinning of the crank; if they are left in, the engine still has a compression stroke and it is very difficult with human power to over come it. You would have to put a big lever arm on the rear wheel, with one rear wheel still on the ground with full vehicle weight, and the front wheels chocked/locked to develop enough torque to spin it. Even then you may spin the other rear wheel if the surface is slick.
It is generally simpler to buy or borrow the wrench you need. The socket/bar or 18" crescent will run $20-$40. If you choose the 18" option, make sure you measure the jaw width at maximum opening; not all 18" wrenches are made the same; I have one that doesn't open wide enough, and another that does for this particular nut.
