2004 225 efi BOG HELP!!

[parttimefishing]

I have a 2004 merc 225 EFI on a 96 Champion 202. The engine cranks up and idles fine. When i go to get on plane i have a weird part throttle bog around 1800-2500 rpms…. Once it gets past that rpm range it seems to run perfect. Alternator is putting out 14ish volts. I have a brand new battery to put in before i lake test again. I bought a complete powerhead that had a bad cylinder. had a local Certified mercury marine tech rebuild the engine for me. New sleeve, new pistons, rings ect. Injectors were sent off and flow tested ( not sure who did them tho) im also getting a low oil alarm on my smartcraft for the tank on the engine but its never low. (new tank and crankcase pressure check valve) how much oil is it supposed to flow from the boat to the tank? I can work on my own stuff at the house so any help would be greatly appreciated!!

[Savage]

When your getting on plane you should be FULL throttle, NOT "part throttle".

The oil tank on the motor should be 100% full.

[parttimefishing]

Savage, thanks for responding. I understand that it should be at full throttle on plane, but that still doesnt explain the bog. also, i know the oil tank should 100% full, i guess i should have worded my question better. How much oil flow should be from the main tank to the engine mounted tank..... a steady solid stream or a small dribble?

[transdep1]

The flow will very with engine speed,make sure the boat tank lid is tight and hose line are not cracked. Check filter on bottom of cap lid.
Not sure on blog....

[Savage]

Flow is more than a "dribble". Reserve reservoir should fill quickly with the cap loosened. Try adjusting the prop venting for 3500-4000 RPM for the holeshot.

[EuropeanAM]

If you would, please take a moment to review the Announcements at the top of the Forum, and be sure to provide the Required Info when posting. Thanks!

[parttimefishing]

I do apologize Mr Don. my 1st time posting and i got a little excited. Engine is a 2004 merc 225 efi 3.0l sn OT944657 model 1225413CD 25pitch trophy. smartcraft guage. boat is a 1996 ChampioN 202. i dont know current max rpm because the engine is still in break in from being rebuilt. If i forgot some info ( im sure i probably did ) please let me know. THANKS!!

[EuropeanAM]

Thanks- the required item is the Serial Number (though the other info is definitely helpful).

You're really not going to be running the engine in that RPM range much, as the boat cannot plane off unless you hit the throttle and provide enough power to purge the WATER from the EXHAUST HOUSING. That's the purpose of the PVS plugs in your prop- they allow you to "fine tune" ventilation that lets the prop gain speed before it "bites" (thus allowing you to clear the exhaust and make good power).

If there is some specific operation you're trying to achieve outside of the above explanation, please clarify.

[parttimefishing]

Im just trying to make sure the break in is done correctly and the bog was bothering me. Im gonna take it back out this weekend to give it another shot. im trying to get used to how the boat performs and acts as it is my 1st true bass boat. ive had flat boats, deck boats, pontoon ect so anything that doesn't feel or sound right it bothers me. The low oil alarm keeps going off when im on the water. As soon as it goes off ill shut the engine down pull the cowl off and and tank is full. its a new tank and sensor. little annoying.

[EuropeanAM]

Unless you have a Smartcraft Instrument or Warning Light that is specifically indicating "low oil"- don't rely on the warning horn sequence as an indicator. There are DOZENS of potential causes of a warning horn, many of which can be detrimental to the engine.

[parttimefishing]

My smartcraft does signal low oil alarm, but both tanks are full.

[parttimefishing]

took it out today. She seemed to run fine at the start. still has the part throttle bog, but once your past that it jumped out of the hole and ran smooth. Ran steady for probably 15 min. shut it off and did a little fishing... about 20-30 min later went to crank her up and it acted like it couldnt find its idle. bounced from 450-650 rpms. got it up and going then about 5 min later i noticed the low oil alarm on my smartcraft going off. so i idled down, shut it off, pulled the cowl and just as i suspected the oil tank was slam full. cranked it up and the same thing, couldnt find a steady idle, this time it would not get on plane and acted like it was running on 4 or 5 cylinders. would not run over 4500 rpms all the way back to the dock. if i put it in neutral and rev it up it would almost cut off the rpms dipped so low. it seems like once its been running for a while the problems start. Im gonna take it to the Tech this week and see if they can figure out whats wrong but i was hoping to figure it out on my own ( with a little help from Mr Don and the forum )

[parttimefishing]

also, when i run it at home on the muffs i can rev it up but when it comes back down it will die unless i feather the throttle

[Savage]

You should never rev the motor out of gear because this will produce faults. Make sure you tell the tech that you did this, so he isn't chasing a problem that doesn't exist.

[parttimefishing]

Savage, thanks for letting me know that... learn something new every day! Other than that do you have an idea of what or why I'm having the other issues?

[Savage]

I think the Tech that rebuilt your motor needs to address your problems, that why you paid him.

[EuropeanAM]

I think the Tech that rebuilt your motor needs to address your problems, that why you paid him.

I would concur with this... and will add that you really should not continue to run the engine until these problems are properly addressed.

[parttimefishing]

Thank you ALL for the info and reply's. Taking it back Saturday to drop it off. hopefully get it all worked out next week.

[parttimefishing]

Morning fellas!! Took it to the mechanic Saturday
Compression was 130 on all 6
Spark was good and strong
Fuel pressure was where it needed to be
Everything checked out perfectly
Dump it in the test tank and it still won't get up over 1900 rpms... he turns and tells me " pull 2 pvs plugs from the prop " and that was all it took!
Lake tested it after that and she runs like a top! Super stoked to get back out there and get that boat dialed in. Thanks again for all the help.

[Savage]

Good...…..but PVS plugs did NOT fix your Alarm.