Boat

Have Boat Questions? Ask a Boat Repair Expert.

Ask an Expert,
Get an Answer ASAP!

I have twin 2001 mercury 250 efi outboards they start run great…

Customer Question
I have twin 2001 mercury...
I have twin 2001 mercury 250 efi outboards they start run great when you are in the water idleing they are fine once you get out and go to throttle up they bog and will not go over 1800 rpm but if I neutral the motors and throttle them up they will slowly get up to higher rpms once it gets to about 4000rpm it is like they clear out and rev no problem then I can put it in gear and the boat takes off no problem and runs great 6000rpm I have replaced spark plugs (champion ql77cc gap 35) both fuel pumps are new all new injectors I am at a loss any suggestions
Submitted: 3 years ago.Category: Boat
Show More
Show Less
Ask Your Own Boat Question
Customer reply replied 3 years ago
also did fuel filters
Answered in 4 hours by:
5/30/2015
Marine Mechanic: Charles, Marine Mechanic replied 3 years ago
Charles
Charles, Marine Mechanic
Category: Boat
Satisfied Customers: 4,922
Experience: US Navy (Ret) Certified Mercury Marine Tech with over a decade of repair experience.
Verified
Hello, my name is***** you for allowing me to assist you today.
Does both engines behave the same way?
would you please post the serial number from one of the engines?
Ask Your Own Boat Question
Customer reply replied 3 years ago
yes they do the left one more than the right one but both do serial# ***** (###) ###-####xlefi
Marine Mechanic: Charles, Marine Mechanic replied 3 years ago
Have you done a compression test on the engines yet?
Ask Your Own Boat Question
Customer reply replied 3 years ago
yes the lowest one was at 120psi but all where 128 or better
Marine Mechanic: Charles, Marine Mechanic replied 3 years ago
OK, that is really good.
Are the engines rather smokey at first start, maybe even hard to start?
Can you remove one of the gear cases to check on an issue with the early 3.0L engines?
Ask Your Own Boat Question
Customer reply replied 3 years ago
they fire right up yes they smoke a little and yes I can remove a gear case if need be
Marine Mechanic: Charles, Marine Mechanic replied 3 years ago
I would like for you to remove the case from the engine that is running the worst. You would then look up at the exhaust ports in the exhaust pipe. See if they are plugged with carbon.
What kind of oil do you use?
Ask Your Own Boat Question
Was this answer helpful?

How JustAnswer works

step-image
Describe your issueThe assistant will guide you
step-image
Chat 1:1 with a marine mechanicLicensed Experts are available 24/7
step-image
100% satisfaction guaranteeGet all the answers you need
Ask Dominick Your Own Question
Dominick
Dominick
Dominick, Marine Mechanic
Category: Boat
Satisfied Customers: 1,009
1,009 Satisfied Customers
Experience: 25 Years Experience as Mechanic, 20 Yrs Boat Yard Owner/Mechanic, Factory Certified

Dominick is online now

A new question is answered every 9 seconds

How JustAnswer works:

  • Ask an ExpertExperts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional AnswerVia email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction GuaranteeRate the answer you receive.

JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

What Customers are Saying:

Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.

Mary C.Freshfield, Liverpool, UK

This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!!

AlexLos Angeles, CA

Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult.

GPHesperia, CA

I couldn't be more satisfied! This is the site I will always come to when I need a second opinion.

JustinKernersville, NC

Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around.

EstherWoodstock, NY

Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know.

RobinElkton, Maryland

He answered my question promptly and gave me accurate, detailed information. If all of your experts are half as good, you have a great thing going here.

DianeDallas, TX

< Previous | Next >

Meet the Experts:

Dominick

Dominick

Marine Mechanic

1,009 satisfied customers

25 Years Experience as Mechanic, 20 Yrs Boat Yard Owner/Mechanic, Factory Certified

Ted G.

Ted G.

Rigger, Diagnostician

704 satisfied customers

40 years boating, Safe boating instruct., Offshore Race promoter, Failure Analysis, Expert Witness

John White

John White

Marine Mechanic

306 satisfied customers

11 years experience working on outboards, inboards, sterndrives & pwcs

Jason

Jason

Marine Mechanic

17,310 satisfied customers

Degree in Marine Technology. Gas and diesel marine mechanic.

Tan

Tan

MerCruiser Certified Technician

11,264 satisfied customers

40 yrs. experience with complete engine repairs both inboard/outboard and MerCruiser Certified Technician.

Jeff G.

Jeff G.

Marine Mechanic

4,729 satisfied customers

42 years experience, Certified Master Technician, All Major Outboards, Sterndrives, Hi-Performance

Captain Dave

Captain Dave

Marine Mechanic

2,672 satisfied customers

USCG Licensed Captain, 20+ Years Boating, Fishing, Maintenance and Repair Experience

< Previous | Next >

Related Boat Questions
When throttling up the engine starts bogging down and will
when throttling up the engine starts bogging down and will finally go back to idle … read more
Charles
Charles
Marine Mechanic
4,922 satisfied customers
MY 2002 MERCURY 50HP EFI BIGFOOT STARTS RIGHT UP AND IDLES
MY 2002 MERCURY 50HP EFI BIGFOOT STARTS RIGHT UP AND IDLES FINE BUT WHEN THE THROTTLE IS ALL THE WAY OPEN IT FEELS LIKE ITS LOST POWER AND THE RPM GAUGE READS 5000RPM WHEN IT HAS ALWAYS READ 5800- 600… read more
Ted G.
Ted G.
Rigger, Diagnostician
Vocational, Technical or Trade Scho
704 satisfied customers
I bought a Boat. A really nice shop kept 1996 bass boat. The
Good Afternoon: I bought a Boat. A really nice shop kept 1996 bass boat. The mercury 115hp is the one that came with the boat. The owner hardly ever ran the boat. His wife had it covered with sheets. … read more
Tan
Tan
MerCruiser Certified Technician
Certified Marine Technician
11,264 satisfied customers
1999 mercury 225 sport max seems to load up at idle & dies
1999 mercury 225 sport max seems to load up at idle & dies at times? … read more
Charles
Charles
Marine Mechanic
4,922 satisfied customers
I have a 06 mercury 40hp EFI 3cyl outboard motor. It runs great
I have a 06 mercury 40hp EFI 3cyl outboard motor. It runs great out of water with a hose connected to it. When I put the boat in the water it takes off just fine then drops RPM's. It's suppose to run … read more
Charles
Charles
Marine Mechanic
4,922 satisfied customers
I have a 2002 Mercury 40hp that will not idle smoothly. it
I have a 2002 Mercury 40hp that will not idle smoothly. it pops, sputters, and cuts out. It runs great once I put the power to it. I just spent $300. for my local mercury dealer to rebuild the carb, r… read more
Jason
Jason
Marine Mechanic
Vocational, Technical or Trade Scho
17,310 satisfied customers
I have a 250 efi mercury 1999 and having overheating issue
I have a 250 efi mercury 1999 and having overheating issue at 3000rpm after 3 to 5 minutes of operation?? This has been going on for about a year we have tried everything , popped valves pulled the cy… read more
Charles
Charles
Marine Mechanic
4,922 satisfied customers
I have a 2005 Mercury 225 Saltwater XL efi serial number is
I have a 2005 Mercury 225 Saltwater XL efi serial number is XXXXX Model #(NNN) NNN-NNNN the motor runs excellent but is only getting 1.4 mpg pushing a 24 ft Kenner weight 2350 lbs. Local Mercury man s… read more
Tan
Tan
MerCruiser Certified Technician
Certified Marine Technician
11,264 satisfied customers
I have a pair of counter rotation 225 EFI mercury outboards.
I have a pair of counter rotation 225 EFI mercury outboards. 1996 models. I have been chasing a problem with the but cannot find the problem. I recently purchased this boat with these motors. The engi… read more
Abiorca
Abiorca
Proprietor
Vocational, Technical or Trade Scho
1,768 satisfied customers
Boat motor has been idle for some time. Just started it once
Boat motor has been idle for some time. Just started it once in a while, but did not run it. I still starts and idles fine, but it will not take a load. When excelerating it sputters, misses, bogs dow… read more
Tan
Tan
MerCruiser Certified Technician
Certified Marine Technician
11,264 satisfied customers
I have a 2002 Crusiers 3075 boat with two 5.0 Volvo Penta EFI
I have a 2002 Crusiers 3075 boat with two 5.0 Volvo Penta EFI stern drive engines. The boat was summerized and runs fine at wake speed. When power is applied the port drive bogs down and backfires and… read more
James
James
Certified Marine Mechanic
Vocational, Technical or Trade Scho
4,094 satisfied customers
Hi, I am experiencing a power loss problem with my 03 200hp
Hi, I am experiencing a power loss problem with my 03' 200hp Mercury EFI Saltwater Series outboard. Here are the details- I've had the boat for a year and the engines (twins) have been been running li… read more
Jeff G.
Jeff G.
Marine Mechanic
Vocational, Technical or Trade Scho
4,729 satisfied customers
I have a 1976 Johnson 135 outboard that will start well, but
I have a 1976 Johnson 135 outboard that will start well, but when throttle arm is advanced the boat will only accelerate to a fast trolling speed of maybe 8 mph. The boat is a fiberglass 19 ft tri-hul… read more
Tan
Tan
MerCruiser Certified Technician
Certified Marine Technician
11,264 satisfied customers
my yamaha LZ250TXRB outboard loses power at about 3500 rpms.
my yamaha LZ250TXRB outboard loses power at about 3500 rpms. i have drained all fuel, changed all fuel filters and cleaned water seperaters. any clues to what the problem might be?… read more
Jeremy R
Jeremy R
1,069 satisfied customers
We have a Mercury 225 EFI outboard motor. It says in the
We have a Mercury 225 EFI outboard motor. It say's in the manual it takes a Champion QL77CC spark plug. I can't find those plugs, will the NGK 4322 BR8HS work?… read more
Scott
Scott
Marine technician
Vocational, Technical or Trade Scho
542 satisfied customers
Hi I have a 2004 125hp mercury saltwater series outboard that
Hi I have a 2004 125hp mercury saltwater series outboard that bogs out and stalls when I gun the engine, sometimes it will throttle up but very quickly stalls out. I have fresh fuel,but have not chang… read more
Marc C. Albertson
Marc C. Albertson
Chief Service Technician
Vocational, Technical or Trade Scho
56 satisfied customers
I have a 1978 Johnson 70hp that has a what seems to be a misfire
I have a 1978 Johnson 70hp that has a what seems to be a misfire under load and will not rev over 2500-2600 rpms. It runs fine on the muffs but not during water test. The carbs were rebuilt, the compr… read more
Dr. Joe
Dr. Joe
Bachelor's Degree
198 satisfied customers
Hi, I have a 2004 Mercury 115hp 4-stroke EFI outboard, when
Hi, I have a 2004 Mercury 115hp 4-stroke EFI outboard, when i rev the engine on neutral sounds fine and will rev up till rev limiter, but in gear or under load, it will start bogging past 3500 rpm and… read more
TOM
TOM
Vocational, Technical or Trade Scho
196 satisfied customers
Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Show MoreShow Less

Ask Your Question

x