Darn Jeep !

I've been away from the forum for a couple months because I'm so frustrated with my Jeep. Just now starting to get in the mood to work on it some more, but I need help.

Recap. March of 2007, I got my engine rebuilt by a local shop known to many mechanics to do good work. I installed it myself and hooked it up. It fired right up at idle but ran rich. I found a hole on the intake manifold which I forgot to plug and then plugged it. Ran great at idle in the garage for the initial break in. Changed the oil. Set timing and replaced points. Timing light showed that it runs best at about 15 degrees before TDC. Took it out on a trial ride. Calm easy drive of about 30 minutes. It lacks power. It has a bit of a knock after it warms up and when you have a load on it. Engine temp is perfect. Reset Carburetor according to Weber DGEV specs, to no avail.
Recheck of compression shows 120, 118,120,120. Distributor will only go in one way! (Can't rotate 180).

From reading other recent posts: vacuum leaks are checked by spraying carb cleaner or starting fluid on the vacuum system connections and listen for rpm changes right?

Questions:
Can off timing cause a knock?
Can too rich or lean cause a knock?
Vacuum leak?
Bad engine rebuild?

Next step? Dynamite? CliffJumping?

Thanks

Jim

 

From what I've been reading 15 btdc may be too far advanced. 5-10 degrees seems to be the norm. The knock, especially under load is probably pre-detonation in the cylinder. U may try changing the spark to the 5-10 degree range and adjusting the carb afterward.

 

There is not enough clearance on the distributor bracket to bring the timing to 5-10 degrees. Does this mean the timing gear is on wrong?:?

 

Hook up a vacuum gauge and adjust your timing that way. My timing is set around 10BTDC with a vacuum gage. You can also diagnose alot with the gage. I have most of the stuff if you need to borrow anything I am down the road at Fort Carson. I would be up there to help rather quick, but am deploying in a week and the family time is mucho important right now. Never know, PM me your phone number if I get a short notice break I'll call and see if you are around.

I also slightly modified my bracket by elongating the notch with a drill press. It gave me a bit more adjustment.

You running electric fuel pump or mechanical?

 

I modified my bracket a bit too. Still not perfect though.

I am running mechanical fuel pump. I did not have it rebuilt though. Just bolted it on. Worked fine on the engine before.

 

You can pull the distributor out and move it ONE tooth (between the cam gear and the dizzy gear) at a time to get the housing into a position where the timing will set where you want it to. I'm not sure which way you'd want to go, but it kinda sounds like thats what you need to do.

 

Chuck,

My distributor has what looks like a slightly offset regular screwdriver which fits into corresponding spot deep inside the engine. I don't understand how I can move it at all, let alone one tooth! Are you saying I need to take off the timing gear cover on the front and move the big timing gear one tooth?:?

 

Scratches Head:? Shouldn't be this hard. Spent 2 thousand on it in the last 6 months and can't get it to run.

Tried to turn the rotor shaft 180... well because the screwdriver slot is offset of center. It won't even go in 180 degrees.
Think I'll take in to a mechanic. If that don't work then I'll have a Jeep to sell.

Thanks Guys for the input though. I'll try a little more before I give up.