Timing chain removal - markets for TDC compression don’t line up (1 Viewer)

[lilhelphere]

Hey guys - I bought a 2013 GX late last year, but didn’t realize it was a time bomb with a blown head gasket. I’m in the process of doing the replacement myself. However, I can’t get the timing marks to line up correctly. Is this a big deal considering I’ll be removing it anyways? I’m not sure what to do at this point.

 

[squirrelhunter]

You only worry about the timing marks when you put the chain back on. After that it's like 1 out of every 100 rotations or something that it'll line up again.
Make sure that engine is at TDC and disassemble. Then when you put it back together you use the marks to verify it's still at TDC.

 

[lilhelphere]

How do I verify that it’s on TDC compression? I’ve watched a couple of videos on it, but the screwdriver method isn’t working. The pistons aren’t moving as I turn the crankshaft. Thanks

 

[squirrelhunter]

The pistons have to turn with the crankshaft..
Do you mean the crankshaft won't turn?

The chains and the cams and the pistons all move with the crankshaft.. Are you just loosening the bolt or something attached to the crankshaft but not moving the crankshaft itself?

 

[squirrelhunter]

How do you know the pistons aren't turning?

 

[lilhelphere]

I’m turning the crankshaft clockwise and the chains + cams move. But the pistons don’t seem to move… I’ve stuck a screwdriver in there and that didn’t move, and I attached balloons to gauge air pressure. Those didn’t move either.

 

[r2m]

With all due respect, if you're able to spin (turn) the crank shaft at all, then the pistons have to be moving.
The only reason they wouldn't would be a broken crankshaft, which would be a 1 in a 10 million chance of that being the issue.

 

[squirrelhunter]

I’m turning the crankshaft clockwise and the chains + cams move. But the pistons don’t seem to move… I’ve stuck a screwdriver in there and that didn’t move, and I attached balloons to gauge air pressure. Those didn’t move either.

Your screw driver isn't long enough. You're sticking it down the spark plug hole right?

The diagram in your first post shows you how to put it at top dead center. Ignore the chain marks for now. Look at #1 and #2 points in your first post. Then look at the "b" marks on the cams and make sure they all look like the picture. If your chain marks look good, but your "b" marks don't then rotate it again.

Get a long enough screw driver and you'll see it move, or use a wire coat changer.
Also make sure your at TDC compression not TDC exhaust. The valves should be closed on the first cylinder not open.

 

[squirrelhunter]

I’m turning the crankshaft clockwise and the chains + cams move. But the pistons don’t seem to move… I’ve stuck a screwdriver in there and that didn’t move, and I attached balloons to gauge air pressure. Those didn’t move either.

ignore the marks on the chains, but focus on the marks on the cams/crank the video shows and make sure your car has them in the same position.

 

[lilhelphere]

Your screw driver isn't long enough. You're sticking it down the spark plug hole right?

Yeah, just realized I’m a moron and didn’t remove the spark plug. I removed the chains in the position below after lining up the center portion…. Tomorrow I think I’ll put the chains back on and verify I have TDC compression after removing the spark plug.