2.5 200 carb merc dies when coming off plane after long run & does not like 3k rpm

[CircleHook]

Little help guys- first I am at the beach- fishing- so I need motor to run- 2002 2.5 200 carb
starts and idles fine, acelerates with plenty of power, runs out fine

2 issues: it does not like 3k rpm range - surges - just does not want to be in that range - depending on wave height offshore, sometimes 3k is where I need to be- annoying

Second is after long run- 10 miles - come back on throttle and it just dies- re-starts just fines

I have parts with me- I have extra stators, triggers (flywheel puller and tools), CDMs, fuel pumps and filters- I actually have a whole fully dressed 2.5 150 hp powerhead in the back of my SUV

Ideas?

Yes I am catching fish so that is why I want it to RUN right

Thanks

[CircleHook]

I am going to clean carbs- sure could use a suggestion..........

[j_martin]

What's the boat this engine is mounted on? How is it trimmed at the times it misbehaves?

[CircleHook]

THANKS for response- Boat is a Mako 235 '79 Trim does not bother it- I have run over 300 miles in past 2 weeks- above 4k rpm it runs great- idles and jumps right thur trouble RPM range- back it off to below 4k and it starts to stumble- it will lose power below 4k - yet once idled all the way down- it will power right back up as long as I take it over 4 k mark-
I did go thur carbs - nothing there- clean-
I am starting to think trigger or stator- I have both with me. This is a CDM engine.
I have digtal voltage thur GPS unit - voltage is steady -

[CircleHook]

Lots of dried salt water on port side of block- all the way up the side and on the head- none on other side- I do get a lot of spray coming off transducers that hits side of cowling-
Motor sits back on a jack plate- could salt water be shorting out the spark? only below 4k? That much dried salt- it must be "breathing" it too.

[j_martin]

Lots of dried salt water on port side of block- all the way up the side and on the head- none on other side- I do get a lot of spray coming off transducers that hits side of cowling-
Motor sits back on a jack plate- could salt water be shorting out the spark? only below 4k? That much dried salt- it must be "breathing" it too.

Yikes........just yikes.

[CircleHook]

Just changed stator and trigger- I thought it was fixed but after 15 minutes or so the 3k problem reappeared- no salt on the block -
Built carbs on Monday, checked all hoses, changed stator and trigger just now, I guess I will replace the fuel pump-............ aggrarvating!!!!!!

[j_martin]

Are you sure the vent to the fuel tank isn't blocked?

[CircleHook]

Your ideas are appreciated! Fuel will come out of it when filled up - so I don't think so- it will pull most of 6k and will do 4500K for extended time/distance.
Changed control module, T-stats, fuel pump- dang- there is not much left-
The 15 minute run then act up again made me wonder if it could be a heat issue- T-stats I took out looked OK.
Going to run it is a few minutes-

[CircleHook]

Well something worked !!

[j_martin]

Cooling in a Merc V6 is pretty funky, with thermostat relief, and pressure (poppit) relief. Yer burning 15 GPH of fuel in a 30 pound container. That's about 2 million BTU/Hour. The average big house furnace in the north burns 80,000.

[W2F a V-King]

[QUOTE=CircleHook;

I have parts with me- I have extra stators, triggers (flywheel puller and tools), CDMs, fuel pumps and filters- I actually have a whole fully dressed 2.5 150 hp powerhead in the back of my SUV

Ideas?

Yes I am catching fish so that is why I want it to RUN right

Thanks[/QUOTE]

DA-UUM...And I thought I carried allot of tools and parts... .

I used to fish allot way offshore in my 22 North American CC, and that is why I switched from one 2.4 Merc to 2 2.4 Merc's, so I would always get back in if one failed...... Well....thats not the only reason .... it was really nice to have the bump in speed..from 200 hp to 400 hp ..back when gas was a buck a gallon

Glad you fixed it and happy fishing!!

James

[CircleHook]

yeah- but I still don't know why or what was bad-

[kentz]

run portable tank. you might have debre moving around in tank and moves around alot when slowing down . I had a piece of wood in my pickup one time and real yo oy ride. good luck, hope she keeps runnen.