Hey guys..
need a little help. Z-24 engine seems like it is starving for air/fuel.
about a month ago, it starting putting around pretty bad, and then stopped running all together. Traced it to a new fuel pump, all was well. For about a month. Same symptoms, so I put a better pump on and it ran like a top, for a couple of days. checked the pump, was working fine. started checking all the vac. lines put new plugs in(they were due) again ran great for a day or two.

Noticed while I had the air cleaner off and running, that the 2 tubes coming up from the exhaust manifold were blowing a lot of air into the cleaner housing. I am thinking maybe my exhaust is clogged up causing my problems.??? my muffler does have a couple holes in it on the engine side and the back is even worse.

Any help would be greatly appreciated..

Maybe sticky injectors or clogged cat? Clogged fuel filter? I'd check those.

Mine came with a universal fuel pump. They don't last long but should last longer than a few days. The filters/strainers last even less time but should also last longer than that. Mine vary from several months to a few years. I stopped using the supplied screw-in type filters/strainers that are mounted to the rear end of the pumps and started using a plastic fuel filter fastened by tubes and thus far this seems to be working better for me. My carburetor plunger also tends to tear up rather quickly & it had carburetor trouble when I bought it 7 years ago & the problems come and go but I have a new carburetor ordered and hope that will solve the problem for a long time.