4.3 LX Gen+ Electric fuel pump issue

Good Afternoon,

I have been reading some of the post other boaters posted on this website and I feel like there are very knowledgeable people that provide great advice. I hope that someone can help me with my particular issue, I have spent many hours reading and I feel confident I have found my problem. So I bought a 1997 Glastron 185 boat with a 4.3 LX Gen+ 2 days ago, I knew it had a few issues so no problem, the issue I am encountering is that the last owner cut some of the wires by the electric fuel pump(left side of the block) and then rigged some very weird way to manually start the electric pump by touching the wire to the 12v + on the battery, the issue is when I do that procedure, then start the boat it starts right up, but after about 1-2 minutes of idling ( i assume is the fuel pumped into the carb by me manually activating the pump) it dies due to the fact that there is no electricity going to the pump to bypass the oil pressure switch(I dont think the oil pressure switch is the problem). My questions is how do I correct the wiring issue to ensure that the fuel pump is automated when I start the boat and the fuel pump will then rely on the oil pressure sensor? Any one have a picture of what the wiring is supposed to look like? or can provide an idea?

Any input would be greatly appreciate, I am very capable of fixing things but this i rather have some direction before messing with it. I also dont want to have to pay someone 400 dollars to fix a wire issue on a boat I purchased knowing I would have to get my hands dirty on.

Thank you for all of your time, this is my first boat =)

Phil,
The struggler

Very easy to correct that, If the starter is marine rated there is a small lug on the solenoid furthest away from the block
That supplies direct power during the cranking phase.
Once there is oil pressure the oil pressure switch send 12v directly to the fuel pump
A better way is to install it with a relay because some pumps will draw enough currect to damage the contacts in the pressure switch.

5 is the pressure switch, 6 is the pump

Attached are some pictures I took today for what I was referring. Let me know what you think.

Thanks!

pm me a cell

Just did

Here is what I think.

Get your serial number and go to your local Mercruiser Dealer. Order a new wiring harness for you engine, Best $250 you will spend, and put it back to a factory install. Problem solved. No relay needed.

FYI, Getting information on repairing your boat on this site is great, But, modifying a fuel system different than what the manufacturer has designed is bad. Anyone who advises you to change the fuel system away from manufacturer design and you do it now makes them the manufacturer and liable. The wiring on an electric pump is part of the fuel system.


Next, change that exhaust. They have a kit available. If you don't change/Upgrade that exhaust the fuel pump will not really matter.

Even with a new harness your still left with the low current contacts handling the high current from the fuel pump.
Adding a high current relay only powers the pump and has no effect on the safety requirements for electric fuel pump shut down

Bt Doctur said:

Even with a new harness your still left with the low current contacts handling the high current from the fuel pump.
Adding a high current relay only powers the pump and has no effect on the safety requirements for electric fuel pump shut down

Click to expand...

The pump draws less than 5 amps. The switch is designed for much more and will last for many many years. Adding a relay is not needed. It is just a failure point.