2005 Tahoe Q6 (5.0 MPI) Won't Turnover

markgee

Recruit
Joined
Aug 21, 2022
Messages
4
Went to start my boat the other day and got nothing when turning ignition (not even a click at solenoid). Boat was running and started fine when I ran it last season, although I had to replace the tilt/trim motor in the offseason.

I've done my best to this point trouble shooting, including charging and checking batteries, checking all fuses under the dash, changed the key/ignition switch tested emergency run/shutoff switch and neutral switch on shifter, cleaned all contacts on battery switch etc. I'm getting power at the 50A Circuit breaker, tested the 90A starter fuse and getting power on both sides, even getting power on the solenoid/relay. However, when I jump across the solenoid contacts, I get nothing, (no click or effort to turn over). I've ordered a new solenoid that will show up today, but can't help but wonder if I'm missing something simple, before I contort myself and try to replace the starter itself.
I read in another thread last night that the carbureted version has a 20A ignition fuse somewhere on the engine itself, but was told to start another thread since not all wiring is the same. Does anyone know what I am missing here or if the MPI actually has another fuse other than the one on the main dash panel?
Sorry for the lengthy post, but I wanted to describe as well as possible what's been tried to this point.

Gotta get this thing running for a Powell trip in a few weeks.
Any help is greatly appreciated.
 

markgee

Recruit
Joined
Aug 21, 2022
Messages
4
Went to start my boat the other day and got nothing when turning ignition (not even a click at solenoid). Boat was running and started fine when I ran it last season, although I had to replace the tilt/trim motor in the offseason.

I've done my best to this point trouble shooting, including charging and checking batteries, checking all fuses under the dash, changed the key/ignition switch tested emergency run/shutoff switch and neutral switch on shifter, cleaned all contacts on battery switch etc. I'm getting power at the 50A Circuit breaker, tested the 90A starter fuse and getting power on both sides, even getting power on the solenoid/relay. However, when I jump across the solenoid contacts, I get nothing, (no click or effort to turn over). I've ordered a new solenoid that will show up today, but can't help but wonder if I'm missing something simple, before I contort myself and try to replace the starter itself.
I read in another thread last night that the carbureted version has a 20A ignition fuse somewhere on the engine itself, but was told to start another thread since not all wiring is the same. Does anyone know what I am missing here or if the MPI actually has another fuse other than the one on the main dash panel?
Sorry for the lengthy post, but I wanted to describe as well as possible what's been tried to this point.

Gotta get this thing running for a Powell trip in a few weeks.
Any help is greatly appreciated.
Update... used multi-meter to test 50A breaker for actual voltage and one post with red wire measures 13.5V while the other post with red/purple striped wire measures 7 5V. Does this indicate the breaker is bad and my problem? Any help is greatly appreciated!
 

tpenfield

Moderator
Staff member
Joined
Jul 18, 2011
Messages
17,698
The CB's should not show any appreciable voltage loss. Are you finding the 7.5 volts further down the line of the red/ppl wire?
 

markgee

Recruit
Joined
Aug 21, 2022
Messages
4
Measuring 7.5 at the ignition amd post of starter solenoid/relay too... I was only using test light initially, which is why I thought I had power, but multi-meter seems to support that the voltage drop is due to a faulty or corroded CB. I have a new one on the way and hope that voltage drop is my issue.
 
Top