Re: 1985 GT 150. Fuel pump question.
First off, you need to get original factory pumps for this engine. The upper and lower pumps are a different part number. Just because a pump looks similar does not mean it is equal. I would not run two of the same part number pump. The capacity of the OMC pumps varies, including the size of the nipples on the pump. Check out the original factory parts list and take the original part numbers to a dealer and they will give you the latest superceded part numbers. The latest number are: use 438559 as the upper pump and 393870 as the lower. These are for an 83 application. Yes, an original VRO engine will have just one pulse line fitting on the block. If you examine the block by the one pulse line outlet, you will probably see a screw/plug in the side of the block just above or below. Unscrew that plug and use that as the second port for the other pump. I think you will wind up removing the pulse line hose barb. Keep in mind you are mixing apples and oranges. The 85 VRO pump uses a hose barb to drive the pulse hose. The 83 has two ports on the block and both pumps bolt directly onto the block with an oval gasket. The 83 pumps above are two-port pumps to be bolted directly to the block (for the pulse line.)
