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Compression Or Exhaust Stroke?

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this will sound like a stupid question, so I apologise, but I need to ask to save problems.

I have a new engine (was a testbed engine so never been in car, looks like brand new) All seemed fine, and we dropped subframe, fitted new engine, fitted subframe etc etc. However car would not start.

I have investigated, as there was no compression, and it appears that one cam is 180 degrees out. The cam alignment tool will never fit as when the slot on one cam is above the line of the rocker edge, the other is below.

I have the engine at TDC on no 1 piston, the 6mm bolt fits on the crankshaft pulley so I know its all in time. however how do I know if its on its exhaust or compression stroke, I need to know which cam is out of time?

In my mind I need to get this right or the injectors will fire on the exhaust stroke, or do I not need to worry about this?

Of course I am hoping that this has not caused bent valves/cracked pistons etc. there was certainly no noise or excessive resistance when it was turned over by hand before install, or by the starter motor, unless of course the damage was already done when I bought the engine.

Thanks in advance


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Well, I've answered my own question (lucky as there was no response! This forum is still active isnt it?)

For anyone that wants to know, the no1 cylinder is at TDC on compression stroke when the crankshaft has the 6mm alignment hole at the bottom (you can actually screw a 6mm bolt in to ensure it doesnt move.)

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