How could my timing be 180 out?

[obsolete]

I had my rockers and cam out, and stupidly turned the distributor shaft without the cam installed. No big deal, I thought, I'll just follow the procedure to re-set the timing. With the cam and valvetrain back in, I turned the engine (clockwise) until cylinder 1 was at TDC. I can verify that's correct because I have the oil pan off, and can see that the #1 rod cap is all the way up, and is in line with #2 and #3. In this position, the camshaft locating pin in the timing gear is at the bottom, pointing at the ground, 180 degrees from where the factory service manual says it should be. How is this possible? I left the cam gear on the shelf while I had the valvetrain out, with the chain still attached. Car ran fine when parked.

[JohnnyWadd]

both 1 and 4 are up at the same time fyi

go with the timing mark on car gear at 3 o clock

[obsolete]

You're right, both 1 and 4 are up at the same time...

 

It's too late, I need to go to bed. Thanks.

[ESIrType?]

I've done this more than once (timing out 180). There's an easy way to know. If the valve cover is off, look at the cam gear. There's a dowel pin on it. When number 1 is at TDC the dowel will point to the 12 o'clock position. Once you are at 12 o'clock set your distrib'. I'm sure you know how to set your distrib' from there.

 

Here's something I made and posted a while back. It makes aligning the cam easier. I've installed the cam 1 tooth off a few times. This takes the guess work out of it.

http://www.starquestclub.com/forum/index.php?showtopic=130406entry1277564

 

Shawn

[obsolete]

Hey, that's pretty cool. Thanks.

 

You say not to turn the engine with the cam bolt backed out. Why is that? I was turning it over without the bolt installed, didn't think much of it.

[mistapickles]

There is an easier way... you need the valve cover off. There is a dimple machined in the shaft of the distributor and a dowel pin on the gear of that contacts the cam gear, you need to identify those first. With the valve cover off insert the distributor in part way, line up the dimple with the dowel pin on the gear, insert the distributor all the way and it will be perfectly timed. Note, when the gear makes contact with the cam gear it will rotate the dowel pin down and the dimple and the dowel pin won't be aligned, but that is fine, it'll start right up.

 

EDIT: the engine has to be at TDC, make sure the dowel in the cam gear is at 90 degrees or 12:00. They made this fast and easy to do so any factory worker could do it without any special tools.

Edited March 11, 2013 by mistapickles

[vbrad511]

You're not 180 out. The crank turns twice for each turn of the cam. Intake-down, compression-up, power-down, exhaust-up. You're at TDC between the exhaust stroke and intake stroke. Once more around with the crank and all will be lined back up correctly.