Just finished a fresh re-build of my 22r, but am having issues with the timing. The truck runs like crap and has low end sag and sputtering when I set it to 0 TDC with the vacuum lines plugged on the advanced. My first problem is that the advance is doing nothing when I plug the inner line in, timing just stays at 0. When I set the timing to 8-12 BTDC the rpm increases dramatically, and the truck does not have low-end sag when under load, but the idle is still very random and I have misfires consistently. I just bought a new dizzy with a vacuum advanced, but did not fix the problem. I have replaced every vacuum line in the engine, the AAP and the AAP diaphragm on the carb. Does it seem like I have have jumped a tooth during assembly? the rpm just increase as I go further beyond 12 BTDC.

 

Pull the cover, set it to zero on the crank indicator, put a chopstick into the sparkplug hole, verify the cam dowel is at the twelve position and the chop stick drops down when the crank is rotated in both directions...

 

Is the rotation of the timing chain off a couple rounds from the rotation of the camshaft? It seems that I have to rotate it four times, once past TDC, to get the chain link marks and the sprocket marks to line up, the first rotation to TDC they are off a couple links, but the next time around they are dead center. I have tapped the top piston to make sure my harmonic balancer isn't off, and Its right at 0 when the piston hits the top. My biggest thing is why the Vacuum advanced doesn't advance the timing at idle at all.

 

Make sure #1 piston is TDC compression stroke. #1 spark plug pulled. Stick your thumb over the hole. As the piston comes up on compression stroke, the compression will push on your thumb. If timing marks are right, check the distributor rotor, and see how it lines up. It could be off one tooth. Pull and re-install distributor if need be.

 

Of, all of this matches up, but I think I need to emphasize on the fact that my timing advanced is doing absolutely nothing when disconnecting/re-connecting at idle. Would this be something wrong with my carb? Im thinking about pulling the intake manifold today to check that gasket and seating. Would there be something wrong with the carb that is diminishing the vacuum to the vacuum advanced?

 

Been a long time since I worked on carbs. From what I remember, you need to rev the engine to see the advance in timing with the timing light. Don't remember what it does at idle if anything.

If it's still not working right, pull the vacuum hose off the diaphragm connection, rev the engine, and check to see if you have vacuum at the hose that plugs into the diaphragm. If no vacuum, then a port is clogged or vacuum leak some where.