Thought I’d reach out to see if there are any ideas for a persistent problem with my 1994 Mercruiser ski mag 350.
When she runs, she purrs like a kitten. When she won’t, she won’t start. Until she feels like it again. Along the way, she may start perfectly, rev to 1,200 RPM exactly, and then die hard. You can watch fuel pressure fade until there’s no fuel left and it dies. It’s like the start sequence is stable and the run sequence is not. Unless it wants to be...
Comprehensive tune up complete. Compression test normal.
New distributor and ICM and ignition coil. NOID lights positive. TBI rebuilt.
VST disassembled and fully cleaned.
New fuel filter.
Main relays checked.
Alternator bench tested, checked out fine.
All connections throughout ignition and charging systems were removed, cleaned, resistance tested and reinstalled.
As you can see, it’s been a mixed bag of block and tackle diagnostics with throwing parts at it out of desperation.
Help? It’s been going on for years, I’ve been through 3 different mechanics, two of whom fired me as a customer, not for being unpleasant, but for lack of anything else to try. The boat is old enough there aren’t that many diagnostic codes that are available from connecting to a computer
As I say, when she runs, she runs great. I’m the original owner. The wife is reluctant to get on board, as am I, for fear of getting stranded yet again. I’d really like to fix the problem for good, get the boat back to predictable behavior. She’s served as a dream boat until ~2015. Never a blip, challenge or expense beyond normal maintenance.
The sporadic nature of the problem makes it insanely difficult to diagnose. You can’t force her to misbehave. As much as I’d love to pay a mechanic worth his salt to come along for every excursion in the event she decides to misbehave, it just isn’t practical...
Any and all ideas welcomed.
When she runs, she purrs like a kitten. When she won’t, she won’t start. Until she feels like it again. Along the way, she may start perfectly, rev to 1,200 RPM exactly, and then die hard. You can watch fuel pressure fade until there’s no fuel left and it dies. It’s like the start sequence is stable and the run sequence is not. Unless it wants to be...
Comprehensive tune up complete. Compression test normal.
New distributor and ICM and ignition coil. NOID lights positive. TBI rebuilt.
VST disassembled and fully cleaned.
New fuel filter.
Main relays checked.
Alternator bench tested, checked out fine.
All connections throughout ignition and charging systems were removed, cleaned, resistance tested and reinstalled.
As you can see, it’s been a mixed bag of block and tackle diagnostics with throwing parts at it out of desperation.
Help? It’s been going on for years, I’ve been through 3 different mechanics, two of whom fired me as a customer, not for being unpleasant, but for lack of anything else to try. The boat is old enough there aren’t that many diagnostic codes that are available from connecting to a computer
As I say, when she runs, she runs great. I’m the original owner. The wife is reluctant to get on board, as am I, for fear of getting stranded yet again. I’d really like to fix the problem for good, get the boat back to predictable behavior. She’s served as a dream boat until ~2015. Never a blip, challenge or expense beyond normal maintenance.
The sporadic nature of the problem makes it insanely difficult to diagnose. You can’t force her to misbehave. As much as I’d love to pay a mechanic worth his salt to come along for every excursion in the event she decides to misbehave, it just isn’t practical...
Any and all ideas welcomed.