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ChrisN

Headless TDC?

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After I had removed my head I rotated the crank to examine the cylinder walls. They all look good but now I can't determine whether the pistons are aligned on the compression or exhaust stroke.

The photo shows position of the pistons at TDC when removed and I can't located the timing mark on the flywheel.

Anyone have a suggestion on how to get back to TDC before I reinstall the head?

Thanks,

Chris

post-108-13667574467715_thumb.jpg

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ummm, if the head is gone, it doesn't matter if its on the exhaust or compression stroke, they're the same. That only matters for the valvetrain in the head.

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Guest Anonymous

looking at the shortblock. This of course would be cylinder #1 which is the cylinder closest to the radiator. It only becomes a stroke when the valves are added into the equation.

shermanmartinez@hotmail.com

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Once you put the head onto the block, you must make sure that you aren't off a link in the timing chain. The most certain way to do this is to look for the magic letters "OT" through the hole.

Once you bolt things back together, gently turn the engine with wrench/socket on crank pulley nut and make sure (again) that the valves and pistons are properly aligned.

Regards,

John N

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looking at the shortblock. This of course would be cylinder #1 which is the cylinder closest to the radiator. It only becomes a stroke when the valves are added into the equation.

shermanmartinez@hotmail.com

What is the difference? Actually, I never really understood the whole M10 short block/long block thing. I thought they were all the same.

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It took a mirror to find it but the magic OT appeared through the hole (phew!).

So, given that the shop has set the valvetrain to TDC, once the head is on and chain is reinstalled, it should be good to go, yes?

I know I'll only get one chance to get it right, just want to be sure.

Chris

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short block refers to the engine block/crank/rods/pistons

long block refers to the complete engine incl. cylinder head/valve train

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So, given that the shop has set the valvetrain to TDC, once the head is on and chain is reinstalled, it should be good to go, yes?

I know I'll only get one chance to get it right, just want to be sure.

Chris

DON'T TRUST THE SHOP! There are marks on the cam and timing chain gear to tell if it is at TDC. There should also be some on the crank pully and the pointer. Also the no 1 valves should be closed. Put no 1 piston at tdc and see where the mark on the main pully is. Get out the manual and make sure your settin it up right. You may only get one chance.

John

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there was a mark on the cam chain pulley carrier that lined up with the oiler tube. I just noted that it is again exactly at 12 o'clock. Any reason why this ain't the way it should be?

Thanks

Chris

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I think there is a line on the flange that holds the cam sproket that lines up with a line on the head to tell you if the head is at TDC.

C.D.! Where are the diagrams?

I just don't have any handy.

John

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