First off, I would like to say that I feel this is the best motor ever made by Mercury. Until now I haven't had a single problem with it and a search of the forums show little to no issues with it. You go Mercury. Now my problem:
My motor, 1998 40/30 jet, oil injected, 3 cyclinder. Until late in the boating season last year, all I had to do to start the engine if just a little warm, even after sitting idle for a few hours, was hit the key. It started immediately. When totally cold I used the cold start procedure and it fired almost as quickly. Those days are over! Believe it or not, last year I changed the spark plugs for the first time, only at the urging of my boating buddies. The old were in good shape yet but I did it anyways. Talking to service manager at my local Bass Pro Shop, he suggested I rebuild the fuel pump. Which I did. New plugs were NGK XXX (can't remember exactly), gapped to .040". Having done that and not experiencing any better results here is the scenario: cold start: Pressurize fuel line, advance throttle, push key to prime/choke, turn key to start. At this time it will crank for quite awhile (15-20 seconds, maybe) before coming to life. Warm start: do not normally have to re-pressurize fuel line even after sitting idle for quite awhile, turn key (very rarley push key to prime/choke), engine starts within mere seconds.
Nowadays it seems as though, even if the engine is somewhat warm, I turn the key and it cranks for 10-15 seconds before I turn off. I then either push key to prime/choke and turn key. It may or may not start within 10-15 seconds. If it doesn't, I go into cold start procedure, here it cranks like it hasn't been started in weeks, before coming to life.
Thinking I had a fuel/air inleakage issue, because it seemed as though it needed gas because the carbs were empty, I changed the fuel lines and bulb (had original. Installed new disposable gasket, verified pick up tube was open and no obstructions within tank. Removed factory installed filter and verified fully open. Reinstalled. Vent cap on tank, open. None of this seemed to make a difference.
This may sound minor to some, but I am so accustomed to my engine firing on slightest turning of the key that it is aggravating to me. Another observation to help you in troubleshooting. Since this issue started last year, I seem to think the engine doesn't sound quite like it used to, (although it runs great). It sounds to me that it is like an automotive engine of old with a slight exhaust leak, maybe in the header area. It is slight, and I seem to be the only one that hears it.
Yesterday I pulled the plugs and verified gap and no fouling. Plugs seemed okay, a little wet, but dark around the entire fire area.
Having read my book, I hope some of you have some ideas for me to try before I take it to the shop, (at the end of the season, that is).
Thank you.
My motor, 1998 40/30 jet, oil injected, 3 cyclinder. Until late in the boating season last year, all I had to do to start the engine if just a little warm, even after sitting idle for a few hours, was hit the key. It started immediately. When totally cold I used the cold start procedure and it fired almost as quickly. Those days are over! Believe it or not, last year I changed the spark plugs for the first time, only at the urging of my boating buddies. The old were in good shape yet but I did it anyways. Talking to service manager at my local Bass Pro Shop, he suggested I rebuild the fuel pump. Which I did. New plugs were NGK XXX (can't remember exactly), gapped to .040". Having done that and not experiencing any better results here is the scenario: cold start: Pressurize fuel line, advance throttle, push key to prime/choke, turn key to start. At this time it will crank for quite awhile (15-20 seconds, maybe) before coming to life. Warm start: do not normally have to re-pressurize fuel line even after sitting idle for quite awhile, turn key (very rarley push key to prime/choke), engine starts within mere seconds.
Nowadays it seems as though, even if the engine is somewhat warm, I turn the key and it cranks for 10-15 seconds before I turn off. I then either push key to prime/choke and turn key. It may or may not start within 10-15 seconds. If it doesn't, I go into cold start procedure, here it cranks like it hasn't been started in weeks, before coming to life.
Thinking I had a fuel/air inleakage issue, because it seemed as though it needed gas because the carbs were empty, I changed the fuel lines and bulb (had original. Installed new disposable gasket, verified pick up tube was open and no obstructions within tank. Removed factory installed filter and verified fully open. Reinstalled. Vent cap on tank, open. None of this seemed to make a difference.
This may sound minor to some, but I am so accustomed to my engine firing on slightest turning of the key that it is aggravating to me. Another observation to help you in troubleshooting. Since this issue started last year, I seem to think the engine doesn't sound quite like it used to, (although it runs great). It sounds to me that it is like an automotive engine of old with a slight exhaust leak, maybe in the header area. It is slight, and I seem to be the only one that hears it.
Yesterday I pulled the plugs and verified gap and no fouling. Plugs seemed okay, a little wet, but dark around the entire fire area.
Having read my book, I hope some of you have some ideas for me to try before I take it to the shop, (at the end of the season, that is).
Thank you.