2.7 Timing Struggles!

[wellinginc1]

1974 2.7 California Spec car, no smog equip on it.

Ive removed the drivers valve cover to verify it on Z1 and 1st cylinder TDC. Set the rotor to the notch in the distributor and the car still does not start, and backfires.

I am not sure what to do as this is what Ive seen the procedure is.

Please help

[RSTarga]

Have you changed the points and gapped them?

[Walter_Middie]

Now that you have piston #1 at TDC at the end of the compression stroke, rotate the distributor so that the rotor points to plug wire #1 position on the distributor cap. To do this, put the cap on the distributor, and see if there is already a mark on the distributor where plug wire #1 position is. If there is not, make a mark with a pencil or a piece of tape. Rotate the distributor so that the rotor ends up pointing at the mark you made for #1 spark plug position.

Just snug up the hold down bolt and see if the car will start. Once the car starts, you can check the timing with a timing light. I like to use a dial in timing light to make setting the total timing easier. Your timing specification is usually shown at both idle (initial timing is 5 deg ATDC) and at 6000 RPM (total timing is 32 to 38 deg BTDC). You should have the vacuum line disconnected and plugged with a bolt or golf tee. One nice thing about setting the total timing at 6000 RPM is that it doesn’t matter if the vacuum is connected or not – the engine doesn’t have much vacuum when the throttle is opened this far. First set your initial timing at idle – rotate the distributor until you get close to where the initial timing spec is for your car (5 deg ATDC). Now set your timing light to the total timing spec (32 to 38 degrees). With the car idling, line up your light on the timing pulley and then rev the engine. You will see the timing marks advance and then stop (if your advance is working correctly) and let the engine return to idle. Where the advance stopped is the total timing. If this isn’t at the 32 to 38 degrees desired, rotate the distributor slightly and try it again. You shouldn’t have to sit at 6000 RPM, just rev the engine quickly and note where the timing stops advancing. Rotate the distributor at idle and try again until you get the total advance desired – regardless of where the initial timing ends up. The total timing is the more important setting to maximize acceleration.

[wellinginc1]

Originally Posted by RSTarga

Have you changed the points and gapped them?

I have some sort of fancy points setup that doesn't have the traditional points look to them or adjustment

[wellinginc1]

Originally Posted by Walter_Middie

Now that you have piston #1 at TDC at the end of the compression stroke, rotate the distributor so that the rotor points to plug wire #1 position on the distributor cap. To do this, put the cap on the distributor, and see if there is already a mark on the distributor where plug wire #1 position is. If there is not, make a mark with a pencil or a piece of tape. Rotate the distributor so that the rotor ends up pointing at the mark you made for #1 spark plug position.

Just snug up the hold down bolt and see if the car will start. Once the car starts, you can check the timing with a timing light. I like to use a dial in timing light to make setting the total timing easier. Your timing specification is usually shown at both idle (initial timing is 5 deg ATDC) and at 6000 RPM (total timing is 32 to 38 deg BTDC). You should have the vacuum line disconnected and plugged with a bolt or golf tee. One nice thing about setting the total timing at 6000 RPM is that it doesn’t matter if the vacuum is connected or not – the engine doesn’t have much vacuum when the throttle is opened this far. First set your initial timing at idle – rotate the distributor until you get close to where the initial timing spec is for your car (5 deg ATDC). Now set your timing light to the total timing spec (32 to 38 degrees). With the car idling, line up your light on the timing pulley and then rev the engine. You will see the timing marks advance and then stop (if your advance is working correctly) and let the engine return to idle. Where the advance stopped is the total timing. If this isn’t at the 32 to 38 degrees desired, rotate the distributor slightly and try it again. You shouldn’t have to sit at 6000 RPM, just rev the engine quickly and note where the timing stops advancing. Rotate the distributor at idle and try again until you get the total advance desired – regardless of where the initial timing ends up. The total timing is the more important setting to maximize acceleration.

I did this, The odd thing was as I was adjusting my valves the car started fine after but they were a bit loose so I re-did them. Of course I noticed the notch on the distributor was not lines up with the rotor when at TDC and this is where I fixed that and lost my timing and it has not been the same since.

[RSTarga]

When did it last run?

[wellinginc1]

Originally Posted by RSTarga

When did it last run?

Few days ago after I finished the valve adjustment, I saw the rotor on the distributor was not lined up while at TDC so I pulled it up and aligned it and that's where it went left, I can not match up what it used to be with being at TDC even

[Walter_Middie]

I can not match up what it used to be with being at TDC even

Are you sure you are on the compression stroke and not on the exhaust stroke? If you have the upper valve cover off, is the #1 intake valve loose? If the valve is tight, then you are on the exhaust stroke, and the rotor will be pointing the wrong direction.

I assume you have not removed the distributor? The rotor has a notch in it and you shouldn't be able to install the rotor at any position - it only goes on one way.

[wellinginc1]

Originally Posted by Walter_Middie

Are you sure you are on the compression stroke and not on the exhaust stroke? If you have the upper valve cover off, is the #1 intake valve loose? If the valve is tight, then you are on the exhaust stroke, and the rotor will be pointing the wrong direction.

I assume you have not removed the distributor? The rotor has a notch in it and you shouldn't be able to install the rotor at any position - it only goes on one way.

Yes it was at tdc on cyl 1 compression stroke when the rotor was set to line with with the notch on the distributor.

[wellinginc1]

The car turns over but will not run. And backfires as loud as a gunshot at times

[boyt911sc]

Could you post a picture of the distributor and rotor (cap removed) @ Z1? Thanks.

Tony

[wellinginc1]

Originally Posted by boyt911sc

Could you post a picture of the distributor and rotor (cap removed) @ Z1? Thanks.

Tony

My finger is on plug wire 1, pink mark is the notch

[nomore]

distributor shaft and rotor are 180 out. Did you have the distributor out?

[manbridge 74]

Rotor tip is facing the opposite way, reinstall distributor.

[boyt911sc]

This motor will never run because the OP had incorrectly set the valve timing at the wrong stroke (exhaust or expansion). It should be done @Z1 TDC (compression stroke). The ignition rotor should be pointing toward #1 (scribed mark on dizzy). The picture shows the ignition rotor pointing to #4 NOT #1. Pull the ignition distributor and re-set it to point toward the #1 marker on dizzy.

Tony

[wellinginc1]

Originally Posted by nomore

distributor shaft and rotor are 180 out. Did you have the distributor out?

Yes and obviously I installed it back wrong. So the rotor is pointing at plug one. Can some describe how it’s backwards and what I should do with a photo or video?

[wellinginc1]

Originally Posted by nomore

distributor shaft and rotor are 180 out. Did you have the distributor out?

So the little copper thing sticking up isn’t what comes into contact with the cap to fire? That’s where I might be off

What does the front of the rotor look like

[boyt911sc]

Originally Posted by wellinginc1

My finger is on plug wire 1, pink mark is the notch

Take another picture of the ignition distributor with cap removed and showing the distributor rotor (@ Z1). Will explain to you which end of the rotor should be pointing toward the scribed mark. Just hold the distributor cap away and take a picture.

Tony

[gled49]

The tab you’re seeing is the ground for the rev-limiting rotor, the rotor contact is flat and brass looking on the other end. Also the red and black colored wires indicate a Pertronix in place of the points.

[al lkosmal]

You currently do not have the correct contact part of the rotor aligned with the distributor notch.....

With #1 at TDC, pull the distributor up until you can rotate the rotor and align the rotor contact to the dizzy notch.....




regards,
al