Combines smoke but no power

Tips cannot be installed on these injectors wrong,but the injector can be in the head wrong.Be sure return line is toward valve cover.

Is my fuel pump bad or do I need to check something else.

Check that the fuel cap breather hole is completely clear. Tie a rag or place a small tin over the cap to protect the fuel tank breather hole from blocking with dust. Check all aircleaner pipes and precleaners. Good luck!

Have you had the injection pump offIJ Is there more smoke noticably coming from the vent tubeIJ what about valve clearancesIJ

AMBac equiped Allis engine run quite clean out the exhaust if everything is right and it isn't overfueled to death. If engine is able to get air and fuel and timing of pump isn't off I would switch injector tips no matter how they check out. Seems like after they have been in there long enough and set up a time or two the lift gets off or something. The tip may check out perfectly good but engine smokes. Install a new set of tips and away you go. Oh yea I have found tips or should I say injector assemblys turned in head 180 degrees many times when job was performed by someone unfamiliar with the way Allis did it. Good luck