Hey,
I am new to the forum and seeking some help with my 50hp Mariner.
The issue: Took her out a few weeks ago and up on the plane cruising, then with the throttle fully forward the engine cut itself back to almost an idle just leaving us to limp back to the boat ramp.
Initially I thought it was a fuel delivery issue as the fuel hose was pretty bad with air leaks at most joins, I manufactured a new hose with automotive fuel hose thinking it would be ready for the next weekend!
Went out the following weekend... something happened and also with the throttle FWD it was surging and back to low revs all the way back. During fault diagnosis I can’t replicate the fault under load but it is miss firing at mid throttle.
Fault diagnosis carried out so far:
Compression test
All fuel filters replaced
Initial fuel pump diaphragm inspection (haven’t put them up to the light but they looked in great condition)
Spark plugs replaced
HT leads replaced
Resistance check of coils
Isolate each coil while running by removing lead from spark plug
Stator visual inspection- looked like new
Stator resistance check
Timer assembly visual inspection
Timer assembly resistance check
Timer Volts checked with Peak voltage adapter (did drop put that down to magneto pick up)
Power pack volts with Peak voltage adapter - volts did drop across all cylinders close to misfire!
I am going to check the fuel pump diaphragms closer and vacuum line to the pump.
it looks to me to be the power pack but I don’t want to spend money on that in case it isn’t, in my head it still feels like a fuel issue when driving and it dropped back it felt like the engine was choking.
I’m not too sure what faults the power pack can cause on the engine, any help on this would be greatly appreciated thanks in advance.
Martin
I am new to the forum and seeking some help with my 50hp Mariner.
The issue: Took her out a few weeks ago and up on the plane cruising, then with the throttle fully forward the engine cut itself back to almost an idle just leaving us to limp back to the boat ramp.
Initially I thought it was a fuel delivery issue as the fuel hose was pretty bad with air leaks at most joins, I manufactured a new hose with automotive fuel hose thinking it would be ready for the next weekend!
Went out the following weekend... something happened and also with the throttle FWD it was surging and back to low revs all the way back. During fault diagnosis I can’t replicate the fault under load but it is miss firing at mid throttle.
Fault diagnosis carried out so far:
Compression test
All fuel filters replaced
Initial fuel pump diaphragm inspection (haven’t put them up to the light but they looked in great condition)
Spark plugs replaced
HT leads replaced
Resistance check of coils
Isolate each coil while running by removing lead from spark plug
Stator visual inspection- looked like new
Stator resistance check
Timer assembly visual inspection
Timer assembly resistance check
Timer Volts checked with Peak voltage adapter (did drop put that down to magneto pick up)
Power pack volts with Peak voltage adapter - volts did drop across all cylinders close to misfire!
I am going to check the fuel pump diaphragms closer and vacuum line to the pump.
it looks to me to be the power pack but I don’t want to spend money on that in case it isn’t, in my head it still feels like a fuel issue when driving and it dropped back it felt like the engine was choking.
I’m not too sure what faults the power pack can cause on the engine, any help on this would be greatly appreciated thanks in advance.
Martin