Finding TDC...Help

I've searched here and other forums, and what I've found relates to having the covers off to do cam swaps.

I need to do a leak down test and need to find TDC and then follow the firing order. Never done this before, but seems easy enough once I find TDC. How do I do this? TIA...

You could take all the cops and plugs out, find #1 cylinder and stick a long wooden dowel down in the hole making sure that it extends out of the spark plug hole on BDC of #1 so it doesn't fall into the cylinder, spin the motor over a few times so you could visualize how the dowel moves up and down and right before it starts back down after you've learned it's movements, that would be TDC.

Maybe not the best way, but it works for my motorcycles. LOL

What's the easiest way to turn the motor, take the belt off and turn the crank pulley?

You shouldn't need to remove the belt. Get a big breaker bar and give the crank pulley a spin.

Quite honestly, the big wooden rod (LOL) method is what I've been using forever and it's never let me down so far.

Remember there are two TDCs---you need to find the one where both valves for that cylinder are closed. Then, by following the firing order, you should be able to turn the balancer 90 degrees and be at TDC for the next cylinder in the firing order.

By removing all of the spark plugs turning over the motor by using a torque wrench will be much easier.

psfracer said:

Remember there are two TDCs---you need to find the one where both valves for that cylinder are closed. Then, by following the firing order, you should be able to turn the balancer 90 degrees and be at TDC for the next cylinder in the firing order.

By removing all of the spark plugs turning over the motor by using a torque wrench will be much easier.

Click to expand...

So how do I determine I'm at the correct TDC?

With the correct TDC, both valves will be closed. THe other TDC will be on the exhaust stroke and the exhaust valve will be open as you come up onto TDC.

If the valve covers will not be off, then just put your thumb over the spark plug hole as someone else turns over the motor by hand. When you feel air pressure against your thumb, that means both valves are closed and the air has no where to go other then pushing on your thumb. The wrong TDC will have the exhaust valve open and you won't feel this pressure on your thumb.

Thank you!!! One other question as I've read conflicting posts. The adapter to thread into the spark plug hole, is it 14mm or 16mm? Thanks Again!!!

M16 x 1.50

Search really does work .... good info for replacing springs