Well, let me first say, I'm a dumbass.



I am building a D16A6 with eagle rods, vitara pistons, etc, the usual. I have the block sitting on an engine stand waiting for the head to go on. Only problem is, when I pulled the head I am using off of the motor it was currently on, I didn't set it to TDC before taking the T-belt off.

Obviously I can line up the marks on the cam gears and line up the marks on the crank pulley and bolt it on, but aren't their rotational speeds different? Like the cam moves twice as fast as the crank pulley, right? So how do i know which rotation to set it on.

My only guess is to go by the valves. With the head off I can spin it around and see which valves are open and closed. When cylinder number one is at TDC, what are the other cylinders valves doing?

If anyone has insight as to how I should make sure the head is at the correct TDC then please enlighten me as it is going in tomorrow.

 

You may be over analyzing this and out foxing yourself.

Here's a easy way to set TDC.

1st have the motor assembled.
2nd remove the #1 spark plug and place a long pencil in the hole.
3rd rotate the crank until the pencil will not move up any higher. Your crank will be set at TDC.
Next, rotate the cam gear until the arrow on the gear is up if the head doesn't have more than 5 thou taken off for flatness.

Your engine should be ready for the timing belt.

 

it will probably be easiest to do it the way mar778c told you, with the engine assembled, and then to just slide the belt on.

 

So it's not like the head will be at a "different" TDC than the block? Is the block marks and the head marks line up then it'll be good?

 

OK, so my plan now is to spin the head around with a wrench on the pulley until it is lined up with the marks, then spin the block around until it is lined up with it's marks, then bolt the two together, slap the belt on and call it a day.

Sound good?

 

yes as long as they are set on cyl # 1, which can be done the way mentioned before

 

But if both pulleys are lined up with the marks, doesn't that mean they are at cyl. #1?

 

assemble the motor, take out or leave out the spark plug in cyl 1, put something long enough down the hole so it sticks out a ways so it doesnt get stuck in the cyl, rotate the crank until the piece you put down the spark plug hole is at its highest point, just take your time, and you should be able to get it dead on, then line up the cam pulley with the head, with arrow pointing up, considering you dont have to much taken off either the head or block, and put the belt on. turn it over a few times when the belt is on and double check the positions of the pulleys, and marks. shouldnt be to hard.

 

Now that i realize that the rotational speed difference makes no difference I get it. i am just psyching myself out.