Warm start issues

[mwinn]

Hello all, hopefully easy resolution. '87 2.4 200 MERC. CCM reeds, heads at 35cc. everything else stock minus oil injection, idle stabilizer etc. issue is after ski run or power run across the lake motor won't restart unless fast idle engaged. Most other times it is a simple tap of the key and she lights right up. Cold starts are typical of carb'ed motor. Unrelated but have owned since new. Motor on '87 Ski Centurion Barefoot Comp. this has been going on for a couple of years and is intermittent but getting annoying. Timing @25 degrees new plugs every othe year, compression 125-130 across all, good gas etc. never done a carb linkage sync. Any ideas out there in SAF Land

[Tritontr19]

Fuel pump diaphragm leaking into block, loading engine with fuel.
Clay

[Merc 2.5]

Fuel pump diaphragm leaking into block, loading engine with fuel.
Clay

I've had this happen ,but will result in very crappy idle ,when it does start, and will have raw fuel run out of prop.. idle timin little low ?? Weak fire when warm??

[mwinn]

Thank you for replies. Fuel pump kit installed first of the season. No reason other it had been many years since last replacement. No effect on issue. Once starte under fast idle everything else is fine and runs clean. Idle may be set a little low. Will adjust this weekend. What about that weak spark thing. Currently newish hi perf wires from Bobs Marine. New wire harness from switch boxes to coils. How else can I amp up the spark. Thanks again, much appreciated

[Merc 2.5]

Weak spark in cracked magnets or heat soak on one of the coils , if all new prob ok , wouldnt hurt test tho , u can get a spark gap tester at local auto parts cheap , would need to check it when warm not wanting to start , but sounds to me it's almost normal , listen me out .... when a motor is set up (timing wise ) its prob being fired up cold (1st start) if idle is high usually shut off , idle down ,restart, all is good , when get to lake and start all is fine , run down lake ,, shut off , wont start ba k unless give little throttle,,,, differences in cold motor and warm imo,,, most have a hot foot and with carbs , like starting on hot rod , give tad gas and fires up.

If u idle it up and run it likely to b to high , will need do idle when its warm and in gear. Maybe this sheds some light on things and nothin really wrong

1 more thang. Will it start fine in yard on hose after warmed up?

[mwinn]

Thank you Merc 2.5. Glad you responded. I enjoy trolling th tech discussions and your responses always come across with a high dose of knowledge and common sense. On the cups or in a tank the motor fires with a bump of the key after warm up. I've owned this boat and motor so long, any thing out of the ordinary I immediately pick up on it. I've got everything dialed in so this annoyance is more of a, I can't figure it out problem, than a real concern. I'll do the spark test and have the coils tested. I'm fortunate to have a good and HONEST boat mechanic close by. Gonna wait until end of season. I'll let you know the results. Thank you again.

[Merc 2.5]

1st I'd try bump idle timin up a hair and c what u get. It's not uncommon for a carb motor start like this if all else is good

[Merc 2.5]

Thank you Merc 2.5. Glad you responded. I enjoy trolling th tech discussions and your responses always come across with a high dose of knowledge and common sense. On the cups or in a tank the motor fires with a bump of the key after warm up. I've owned this boat and motor so long, any thing out of the ordinary I immediately pick up on it. I've got everything dialed in so this annoyance is more of a, I can't figure it out problem, than a real concern. I'll do the spark test and have the coils tested. I'm fortunate to have a good and HONEST boat mechanic close by. Gonna wait until end of season. I'll let you know the results. Thank you again.

Thanks for kind comment but theres alot guys here that know a ton more than I do ,, just glad help when I can, good luck