1973 cj5 304 amc

[74trs]

pulling my hair out.. recently started over heating and running to the point of bucking. Had driven several miles with out a problem. I have read where there were nylon timing gears installed and would shear a tooth? Also have thought that maybe the carb is dirty making it run lean which i beleive could cause the over heating and bucking? I parked it and it has started once since with very rough idle and back firing.

Thanks for the help

 

[oldschoolcj7]

Did you change the distributor?

 

[74trs]

Have not changed the distributor have replaced the points and condenser though but did not correct the problem.

 

[oldschoolcj7]

OK don't think it would be the distributor gears then. If you have a dwell meter you can hook it up and check the bearings in the distributor pretty easy. Might be a timing chain. Bring it up on the timing mark and see if the rotor is pointing to number one on cap, if it's 180 degrees out rotate the crank one more time. Also can watch distributor while turning crank to see if there is a lot of play in it.

 

[74trs]

Rick,
Thanks for the help I will check that tonight.

 

[74trs]

Hey Rick,
I checked these items last night would like to bounce this off you i pulled the number one plug brought the motor to top dead center on compression stroke by doing this shouldnt the timimng mark on the balancer be relativily close to the gauge on the timing chain cover?

Thanks
Tracy

 

[SteelHeadz]

At TDC, compression stroke, it should be close to the 0 mark if not before the 0 TDC mark on the timing cover but within the gauge of the cover. Did you check for intake leaks for the bucking issue?, Pressure test the cooling system for an internal or external coolant leak?. The 304 i had on my Jeep prior to replacing it with a 360 started running hotter that normal and after performing a pressure test , it revealed a leak internal. After checking all the possible areas including the head gasket, i sent the cylinder heads out to get checked for cracks. The machine shop isolated a hairline crack on the right bank of the cylinder head. After replacing that , all is well. Not saying you have the same condition, but it might be something to check for.

 

[oldschoolcj7]

As Mikey say it should be at 0 or before. Might be internal crack in head or block but usually that doesn't cause engine to run rough, but it could.