The problem that never seems to be solved: update. I’ve discovered that if I flip the kill switch I can crank the motor as long as I want with no starter drop out. If I start cranking with the engine killed, flip the switch while cranking the starter drops out immediately. Does this tell me anything? Seems tied to the kill circuit.
Sounds like it might want a little bit more air... perhaps a hair less timing. Would also be interesting to note if unplugging the Air Temp Sensor makes any significant difference.
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
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cranking rpm to low?
Thank You Leon Pugh
Thx. I’ll check those things and report back.
Bear with me as I’m on vacation. Unplugging the air temp sensor, the motor starts the same(like crap), no change at all. I’ll check the crank rpm next time and check the timing once I get home.
thx very much for the input.
Any updates on this problem lately? Just curious since my 200 efi is experiencing the same problem.
I re-set the timing to 2, at idle. I had one water test session and it seems to have helped. Hot starts we’re very good. After dealing with this for quite a while I’m hesitant to say it’s fixed. I’ll need more on water time to verify.
Any updates? I seem to have similar problem.
Very interesting thread! I have worked out all of my issues except starting, the description given by the OP is very familiar! This assumes key is original with push-in option?
How does the EFI enrich? modify injector duration?
Increased pulsewidth.
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
The referenced article stated some motors used temperature to decide whether to enrich, how do you know which ones?
This is going to sound dumb, but my 2.5 efi would do the same thing as yours with the starter disengaging too early and hard to get started warm after multiple attempts. On my boat the ignition was slightly sticky and the key would not go all the way back to the run position when I went to let go of the key (it would stop slightly before the run position). I learned that if I didn't manually move the key back to the run position it would do exactly as you described and be very hard to get started. This probably isn't your problem but it sounds like you have a confusing case on your hands!
Colorado State University Bass Team
2000 Viper Cobra 201D, 200 merc efi
stock ECU uses both air and cyl head for infoOriginally Posted by Daretofish
.................................................. ...the scariest thing in life is the unknown ...................................
+1... Essentially air temp, PORT cylinder head temp, and TPS are all used (then referenced from MAP tables based on RPM and Manifold Pressure).
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
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