Todd320
Well-Known Member
- Jul 21, 2016
- 1,508
- Boat Info
- 2007 Sea Ray 320DA
- Engines
- Twin V-drive 5.7L 350 Horizon
I have 2007 350 MAG MPI horizon engines. Last year, the port engine stopped running. Fuel pump relay burned out. Replaced, ran fine. Next trip, 2 weeks later, engine died again, this time, the harness for the relay was bad. Since then (September-October), no issues. Yesterday, had a great weekend, engines ran great. Put boat on the rack, went to flush it, would not start. Noticed the fuel pump is not making a noise when you put the ignition switch in the on position (like it does on the starboard side).
Replaced the relay, did not fix. I'm thinking the harness again, but also what is the root cause? From what I have gathered by searching this forum, the fuel pump housing is probably "delaminating" and causing high pressure in the fuel system, making the pumps draw too many amps which then are burning up the relay or the harness. Alternatively, I have a short somewhere in the harness that keeps causing this.
Thoughts? I have a call into my tech already, but I have a manorial day trip planned. Not sure he will be able to get to it by then.
As far as diagnosing, if I have a multimeter, what should the pins on the harness read when switch is in the on position? There are 5 pins, if I knew which ones should read 12 volts I could check that and see if I can apply a temp fix to the harness.
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Replaced the relay, did not fix. I'm thinking the harness again, but also what is the root cause? From what I have gathered by searching this forum, the fuel pump housing is probably "delaminating" and causing high pressure in the fuel system, making the pumps draw too many amps which then are burning up the relay or the harness. Alternatively, I have a short somewhere in the harness that keeps causing this.
Thoughts? I have a call into my tech already, but I have a manorial day trip planned. Not sure he will be able to get to it by then.
As far as diagnosing, if I have a multimeter, what should the pins on the harness read when switch is in the on position? There are 5 pins, if I knew which ones should read 12 volts I could check that and see if I can apply a temp fix to the harness.
Sent from my iPhone using Tapatalk