how to tell if head is at TDC?

supraian

New Member
Jan 2, 2006
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san diego
i'm about to put the head back on but wanted to make sure its at tdc, there are marks on the cams but it just doesn't look right so i was wondering how i can double check them looking at the valves or the cam loobs?
 

supraian

New Member
Jan 2, 2006
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san diego
they're up kinda pointing towards each other to a small degree

sm_photo_missing.jpg
 

IJ.

Grumpy Old Man
Mar 30, 2005
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I come from a land down under
Very welcome!

Our motors are fairly safe being Non Interference by design so there's no chance of bending a valve through contact with a piston.

Be careful when the head is off and don't put it Chambers down as the valves stick out and could be bent if they touch the Bench/Floor!
 

suprashy

New Member
Jun 21, 2005
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Nassau County, NY
Ckg. the TSRM, the one thing I'm confused with is that when removing the CPS, it says to make sure the lobe faces up, then turn the crankshaft 120deg. then turn it the other way about 40 deg. IIRC. so that the zero mark lines up with the crankshaft hash mark. This is supposed to be TDC if I understand correctly. I've done that according to the TSRM, but when I look down the oil fill, the lobe does not point up. But is this not TDC? Tks!
I'm planning on installing the CPS this way, cuz this was how I removed it to get to the water jacket I wanted to clean up.


Suprashy
 

souprat

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Mar 30, 2005
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fairfax VA
^^that sounds weird. i dont remember those instructions. dang i wish i had my tsrm with me. to find tdc you would just set the bottome end so that the notch on the crank pully is pointing to the zero mark on the timing belt cover, if the cam lobes are not as they should be then that means the piston is at tdc but its in the exhaust/intake stroke, not the compression stroke. so then you would just turn the engine ovre untill the crank pully lines up and the cam lobes are as they should be. now for the cps, from what i remember just set the engine at tdc and then line the marks up in the cps and slide it into place.
 

suprashy

New Member
Jun 21, 2005
126
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Nassau County, NY
souprat said:
^^that sounds weird. i dont remember those instructions. dang i wish i had my tsrm with me. to find tdc you would just set the bottome end so that the notch on the crank pully is pointing to the zero mark on the timing belt cover, if the cam lobes are not as they should be then that means the piston is at tdc but its in the exhaust/intake stroke, not the compression stroke. so then you would just turn the engine ovre untill the crank pully lines up and the cam lobes are as they should be. now for the cps, from what i remember just set the engine at tdc and then line the marks up in the cps and slide it into place.

Here's what I was referring to turning the crank 120 deg. one way, then about 40 deg. the other way. Didn't understand it, but followed the procedure nonetheless:

http://www.cygnusx1.net/supra/library/TSRM/ig/IG_22.html