How do you tell the difference between an even and odd fire motor

Ok. I have a 1970 CJ-5 with the dauntless V6 motor. I bought it used and don't really know if it's the original motor. I can't get the engine to run for more than a second or two. T he problem started when I installed the re-built distributor. I think the one I got back doesn't match the one I sent. If my motor is an odd fire how should the cam lobes and distributor cap look? My distributor has a narrow lobe, wide lobe, narrow, wide etc. evenly spaced all the way around. The cap has 6 evenly spaced towers on the prestolite distributor. Is this correct? I set the points to open at 5* BTDC and if I move the distributor either way it still won't start. I check each plug with a timing light and they are all firing. I should have taken pictures of my distributor before I sent it to be re-built. How do you tell the difference between an even and odd fire motor in order to install the correct distributor?

 

Check the casting numbers on the engine block. The 225's were odd fire. The even fire engines would be 231's swapped into it by a previous owner. The 231's started out as odd fires and switched to even fire in the mid to late 70's.

There area some differences between the intake and exhaust, but I am not sure if you can tell from the outside of the engine. Castings numbers would probably shed some light on those too.

There are a couple of photo threads out there on the difference between an even fire and the odd fire distributor cap and the delco vs prestolite distributor.

There are some experts on here that may be able to narrow your search if you can post some pictures of the engine.

 

Mid year '77 was the change from oddfire to evenfire.
I would start by resetting your points properly either with a feeler gauge or dwell meter.

Is it getting a steady supply of fuel? Starting, running for a couple seconds, then dying is usually a sign of fuel starvation.

 

Points cap don't have the elongated contacts only the HEI. Sounds like an oddfire distributor from your description of the cam and the fact Buick never had an even fire points distributor. Other than checking the point gap as mentioned did the distributor go into the same position as the old one that came out? If it's out of sequence it can cause a no start or uneven running condition. I know it's been covered here but check this out also.-http://forums.off-road.com/jeepster-american-jeepster-club/60422-odd-firing-oddfire.html

 

I would agree...........although if you know what your looking at the blocks at the bell housing are different between the 225 & 231 along with the casting numbers.

 

Thanks for the advice everyone. The link is very useful...am going to check the point gap and open it up a little. Plus look into the other suggestions. At least I now know I do have a odd-fire distributor and the cap is also correct.

 

Ok, making progress. Opened the point gap to .018 and the dwell is around 28* and it'll run as long as I increase the idle when she's stumbling and about to stall. The timing fluctuates between 0*,5*, or more.The idle mixture is 1 1/2 turns out. Put a spark lite on each plug and they are all firing. Rotated the distributor until it runs the best but can't get it to idle steady. I know there is a leak in the trottle shaft, but it had no problem idling before.I had the carb rebuilt because the vacuum advance didn't work. Checked the pvc and looked for vacuum leaks and can't find anything. Going to play with the idle screws, at least she's running a little.

 

Might want to rotate the crank back and forth while looking at the rotor.....I believe these had plastic coated teeth on the timing gear...............