Jerry is absolutely correct….Many folks waste a lot of energy and frustration pumping those primer bulbs but accomplishing nothing…Holding the bulb vertically, with the arrow pointing up solves this problem…
Back to your question though….Does this engine have the engine fuel connector with the check valve? If so, I’m betting it was jammed/plugged. If not, I’m thinking you freed up some debris while working on the lines. But, there may actually be a kink/flaw in one of the engine inlet fuel lines that might cause trouble again. I guess the only way to confirm this would be to destroy/cut open the inlet fuel lines to look for this condition. You mention that the engine has been converted to a fuel pump, so I’m thinking the original fuel lines were altered/changed to accommodate this change. Perhaps this new plumbing has introduced a pesky intermittent problem…
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