Trying to check timing

[splntrp]

I've been reading posts about how to check / set the timing on my CJ. I have a timing light, that I haven't used in ages, and I understand the basics. But reading posts it says to do certain things when the motor RPM's are in certain ranges. How do I know my RPM's without having a tach?

 

[Torxhead]

I would suggest using a multimeter for the engine rpms. Don't forget to disconnect and plug the distributor vacuum hose. Marking your timing locations with something like a white paint on the vibration dampner will help. Make sure the wires from the timing light and multimeter are clear of things like the fan and exhaust manifolds.

 

[splntrp]

So I would put the meter on the diagnostic ports above the battery? I need to look up the pin layout for those.
Thanks.

 

[Torxhead]

Actually, you could hook the meter into the positive post on the coil and ground the other terminal. Have you seen this?:
Table of Contents
Anybody with a later CJ should have this file handy.

 

[splntrp]

Yes, I've seen that page and reviewed it several times. I ended up buying a new multi-meter from advance auto that will do RPM, dwell, and several more automotive specific things. Ground the negative probe then put the positive probe to the negative side of the coil, per the meters instructions. Tried it last night and it actually worked pretty good. I also bought a vacuum gauge while there. Now if I can just get some time after work to check things out.

Thanks for the help.