I have a '89 w/remote oil injection.  fuel line sporadically loses prime and at times the bulb sucks tight.  Completely replaced fuel lines and bulb and now can't get any prime.  I have also tried different tanks.  There is a translucent cartridge on the side of the oil pump that the line from the tank runs to, and when you pump the bulb gas moves back and forth through it rather than in a single direction.  Can anyone tell me if there is a one-way valve in the oil reservoir that may be the problem?

Any help would be appreciated.

If it's sucking the bulb flat, there is a restriction between the bulb and the pickup in the bottom of the fuel tank. If it's a twin tank boat with a tank selection valve, I would start right there.

Another commom cause it the antisiphon valve in the tanks. This is the fitting on top of the tank the fuel line connects to. There is a one way check ball inside that fitting if someone hasn't already replaced them with a standard barb fitting. If they are still there, throw them away and replace them with a regular barb fitting.  Also make sure the vent is not stopped up, tanks gotta be able to get air to flow fuel.

If it's restricted, it probably won't prime. Also make sure you didn't put the bulb in backwards. Nothing saying the new bulb is any good either. One the one-way check valves in each end of the bulb could be stuck open, if so, you can pump all day and it won't suck fuel.

Are you sure that you installed the new pump/lines correctly? I recently replaced mine and found that the directions on the box of the one i got where wrong! It said install one way and i did and could not get it to prime. I installed it opposite of what the box said and all was well.

Went out armed with your advice along with some google work I did last night and I think I found the problem (2problems).  I think the anti siphon on the old tank was faulty, and when I replaced the fuel lines and bulb was still not getting any pressure.  Somebody on iboats.com noted that some aftermarket bulbs need to be positioned so the flow direction arrow is pointing up when priming.  That worked this morning and it's holding.