SandCruiser
New member
First off thanks for having me. I haven’t owned a boat in 15 years and looking forward to getting back into it…. I think!
Sorry in advance for the long post but details help right?
Last year I purchased my boat with a 92 Johnson 155WTXENE - 90* cross flow that had been sitting for 6 years. Went through all the normal procedures to get it healthy and had it running great before winterizing.
Fast forward to this April… prepared it for the summer and took it out and it ran great until idling, when it started to get temps up to around 203* per an infrared temp gun. Seeing as it had a new water pump kit and needed a temp switch anyway, I decided to go ahead and replace deflectors and cooling system gaskets for the long haul. Did all that and she’s cooling better than before but now comes the major trouble. Runs good on the muffs but only gets to 2500ish rpms under load. I’ve checked compression and all have 81 psi except for the bottom port which is at 75 psi. (Supposedly a commercial engine with low compression heads and I had similar numbers when it was running well.)
I’ve also been through the entire fuel system only leaving out a pressure test and everything else checks out. Yesterday I found only two cylinders have 7/16” spark. Once it was cylinders 2 & 5 and today it was only cylinders 3 & 4. Thought that was odd. So I’ve started testing the ignition systems per the OMC Service Manual. I’ve never used ohms so my numbers may be off but I’m getting there.
I’ll gladly post some ohm results later when I feel more confident in my findings.
So the question… Is there a likely ignition component that may fail because of excessive heat? Also, I’ve read about a shift interrupter switch. I think my issue is bigger than that but does my engine have one? Didn’t see one in marineengine schematic but wanted to ask. Any other tips??
Thanks all!
Sorry in advance for the long post but details help right?
Last year I purchased my boat with a 92 Johnson 155WTXENE - 90* cross flow that had been sitting for 6 years. Went through all the normal procedures to get it healthy and had it running great before winterizing.
Fast forward to this April… prepared it for the summer and took it out and it ran great until idling, when it started to get temps up to around 203* per an infrared temp gun. Seeing as it had a new water pump kit and needed a temp switch anyway, I decided to go ahead and replace deflectors and cooling system gaskets for the long haul. Did all that and she’s cooling better than before but now comes the major trouble. Runs good on the muffs but only gets to 2500ish rpms under load. I’ve checked compression and all have 81 psi except for the bottom port which is at 75 psi. (Supposedly a commercial engine with low compression heads and I had similar numbers when it was running well.)
I’ve also been through the entire fuel system only leaving out a pressure test and everything else checks out. Yesterday I found only two cylinders have 7/16” spark. Once it was cylinders 2 & 5 and today it was only cylinders 3 & 4. Thought that was odd. So I’ve started testing the ignition systems per the OMC Service Manual. I’ve never used ohms so my numbers may be off but I’m getting there.
I’ll gladly post some ohm results later when I feel more confident in my findings.
So the question… Is there a likely ignition component that may fail because of excessive heat? Also, I’ve read about a shift interrupter switch. I think my issue is bigger than that but does my engine have one? Didn’t see one in marineengine schematic but wanted to ask. Any other tips??
Thanks all!
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