Air in fuel

[MuleSkinR]

I have a hand pump(?), when tractor runs but stops I open nut and pump until air bubbles stop, tighten nut, tractor runs fine...all day. Go back 3 days
later....same problem. Am I not doing something right or could there be a pin whole somewhere allowing air in??

 

[showcrop]

Maybe it's a Ford?

 

[Jim.ME]

Sounds like an air leak somewhere. Some hand pumps have been known to go bad and allow air in. It would really be to your benefit, in getting good answers, if you would include what tractor, engine, etc., you are working on when you post a question.
.

 

[MuleSkinR]

Ford 3000 diesel. 47 hp 3cylinder

 

[showcrop]

What makes you suspect the primer pump. I have had the same problem, and I believe that it is usually the fuel filter installation, though one time it was a fuel line fitting. This was on a newer tractor and I just went through and snugged them all. A "pinhole" implies that it is from metal deteriorating. That is very unlikely.

 

[Texasmark1]

My 3000 has fuel line rubber hoses between the filters and the CAV rotary pump inlet. A crack in one of those could let air in but should show diesel, oil accumulating dust on the perimeter of the hose. Anywhere you see that kind of "wet" surface, expect your leakage point.

 

[MuleSkinR]

Thanks for the replies.