1989 Cobra 260hp 5.7 liter fuel pump

This is a 1989 Four Winns 225 Sundowner with a 260hp 5.7 GM engine. Last fall on my last run of the year, I punched the throttle and the engine bogged down like it was starving for fuel. It would get up on plane, but would not run WOT. I am suspicious of the fuel pump, and feel it should be replaced anyway since it is original. I have 2 questions.

1. If memory serves me correctly, these GM engines have a push rod (#11 in parts diagram) to drive the fuel pump. I remember someone telling me to screw a bolt in somewhere to keep the push rod from dropping into the oil pan. The OMC manual says nothing about that. If so where does it sacrew in?

2. The replacement fuel pump as listed by Marineengine is Sierra 18-7268. They do not have the OEM. From the picture the holes do not line up with my fuel lines. Maybe it is as simple as rotating the bottom part of the pump.

I removed the filter-water separator. There was no water in it.

on 1) the magic bolt is the upper (or two) front motor mount holes. getting access may be more hassle than just using a bent hacksaw blade to hold the push rod up...grease will also hold the push rod up but that works best if you make sure the rod is into its bore as far as it goes (rotate the engine by hand ....and the rod won't fall into the pan.

on 2), you can't always tell by the picture unless it has a note indicating its of the part in question. If the outlet doesn't line up in the same spot as the existing pump, many times you can spin the housing as you implied. you can always ask before you order...

Thanks for the reply. Its been 30 years since I replaced a mechanical fuel pump on a small block GM. Glad to hear there is no danger of dropping the push rod.

Thanks

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GregO. said:

This is a 1989 Four Winns 225 Sundowner with a 260hp 5.7 GM engine. Last fall on my last run of the year, I punched the throttle and the engine bogged down like it was starving for fuel. It would get up on plane, but would not run WOT. I am suspicious of the fuel pump, and feel it should be replaced anyway since it is original. I have 2 questions.

1. If memory serves me correctly, these GM engines have a push rod (#11 in parts diagram) to drive the fuel pump. I remember someone telling me to screw a bolt in somewhere to keep the push rod from dropping into the oil pan.
Not possible!

The OMC manual says nothing about that. If so where does it screw in?

As per Mark, it will be the upper threaded hole as shown here.


2. The replacement fuel pump as listed by Marineengine is Sierra 18-7268. They do not have the OEM. From the picture the holes do not line up with my fuel lines. Maybe it is as simple as rotating the bottom part of the pump.

As per Mark again, on a brand new pump, you should be able to loosen the screws and re-index the inlet/outlet ports.

I removed the filter-water separator. There was no water in it.

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