Boat

Have Boat Questions? Ask a Boat Repair Expert.

Connect one-on-one with {0} who will answer your question

This answer was rated:

What are the signs and symptoms if an outboard 2 stroke

where to be running either...
What are the signs and symptoms if an outboard 2 stroke where to be running either to rich or to lean .
Show More
Show Less
Ask Your Own Boat Question
Answered in 2 hours by:
10/11/2020
Marine Mechanic: Yachtwork, Marine Engineer replied 2 years ago
Yachtwork
Yachtwork, Marine Engineer
Category: Boat
Satisfied Customers: 3,735
Experience: MEC3 and RYA Yachtmaster Ocean
Verified

Hello- There are two types of signs and symptoms. The fist is seen. This is what you would experience as the operator. A peppy engine might be running lean. An engine that bogs down might be running too rich. This would be espcilllay true if as you released the throttle the engine got a burst of power, as if you were slowing the throttle lever and the engine picked up power. A smokey engine might be running rich. An engine that is overheating might be running lean. Pinging engines tend to be lean running. In lean engines its not easy to get the throttle stable. It is almost as if the engine is hunting. A lean engine does not have much power. Not bogging, but just not a lot of power. Pops in the intake are good indications of too lean a mixture. The engine runs much better once its warmed up. That is lean or a slightly clogged jet. Lean running engines have whitish plug ends.

A rich engine needs to have a lot of throttles, and soon as the rpm's come up to keep up the power we have to open the throttle, even more, to give more air to overcome the fuel that is now flowing even more so we have to again chase the throttle. Rich engines work well cold, and then fall off when the engine warms up. Dark, black exhause is a good indication of rich, unburned fuel. If the air cleaner is removed rich running engines tend to have a quick improvement.

The general catch-all for adjusting carbs is to-

  1. identify the high-speed air-fuel mixture, the low speed, and the idle.
  2. set the ideal adjustment so the engine runs kind of smooth.
  3. turn the low-speed mixture screw in till the engine drops off. turn the screw outward till the engine drops off. set the screw in the middle.
  4. reset the ideal screw so the engine sounds right, not so slow that if the plug misses a hit the engine dies, but no so fast the gears grind when shifting.
  5. take the boat out and run it up to full speed.
  6. turn the highspeed jet in till the engine begins to bog, then turn the screw out till it begins to bog the set the screw in the middle.

If the adjustments don't work then either the carb is dirty or the points of the needle valves have been ruinded.

Let me know how it goes.

Scott

Yachtwork
Yachtwork, Marine Engineer
Category: Boat
Satisfied Customers: 3,735
Experience: MEC3 and RYA Yachtmaster Ocean
Verified
Yachtwork and 87 other Boat Specialists are ready to help you
Ask your own question now
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 Yachtwork Your Own Question
Yachtwork
Yachtwork
Yachtwork, Marine Engineer
Category: Boat
Satisfied Customers: 3,735
3,735 Satisfied Customers
Experience: MEC3 and RYA Yachtmaster Ocean

Yachtwork is online now

Related Boat Questions
I would just like to chat with a professional marine
I would just like to chat with a professional marine mechanic about my evinrude 80hp … read more
Ted G.
Ted G.
Marine Mechanic
Vocational, Technical or Trade Scho
4,145 satisfied customers
Inherited a pos Mercury 4hp 2 stroke motor. Supposedly runs,
Inherited a pos Mercury 4hp 2 stroke motor. Supposedly runs, yet I can't find any adapter to connect this motor to a fuel tank. Called mercury, they say one comes out of the fuel pump...not on this mo… read more
Charles
Charles
Certified Mercury Tech
5,752 satisfied customers
Outboard motor not running right: 50 HP outboard motor on
Outboard motor not running right:50 HP outboard motor on pontoon boat: - Starts fine... - Will rev up fine in neutral, way up if you want it to... - But you put it in gear and open up the throttle and… read more
Jason
Jason
Marine Mechanic
24,193 satisfied customers
I have a 1999 Mercury 30 HP 2 stroke and took it out last
I have a 1999 Mercury 30 HP 2 stroke and took it out last week and it went up to speed- and then died like I cut off the fuel. It would not restart- have since rebuilt the fuel pump and it starts but … read more
Jason
Jason
Marine Mechanic
24,193 satisfied customers
2000 mercury 25EL serial #ot137316. Motor sat up for a while
2000 mercury 25EL serial #ot137316. Motor sat up for a while in a job relocation. After tune up in run great. Next trip out it would quit after a period of "no-wake" speed. If the elec. choke was pres… read more
Jason
Jason
Marine Mechanic
24,193 satisfied customers
Yamaha 90 4 stroke burns on plug 1 and lean on plugs 2-3 and
Yamaha 90 4 stroke burns rich on plug 1 and lean on plugs 2-3 and 4 Bake fires at 1/2 throttle I have just calebrated the carbs and the carbs were cleaned by another guy. Any suggestions ?… read more
Jason
Jason
Marine Mechanic
24,193 satisfied customers
Hi, Off all the outboard makes would you be able to advise
Hi, Off all the outboard makes would you be able to advise what outboards are available that weigh in up to 160- 180 kg mark, either in 2 stroke or 4 stroke. The transom measurement is 510mm. This mea… read more
Master Tech
Master Tech
Service Manager/Technician
Vocational, Technical or Trade Scho
1,167 satisfied customers
Hello, I have a 1995 Mercury 15 hp 2 stroke outboard. I have
Hello, I have a 1995 Mercury 15 hp 2 stroke outboard. I have located the timing screw, idle adjust screw and lean/rich screw. My question is regarding the lean/rich screw......When I turn the screw cl… read more
Noel Schembri
Noel Schembri
Marine Mechanic
Diploma
3,046 satisfied customers
2000 200HP carb. Johnson outboard 197 hours. Runs great
2000 200HP carb. Johnson outboard 197 hours. Runs great at all speeds except idle in or out of gear. Inconsistantly will misfire. Seems as though it is running rich as plugs (which are brand new) are … read more
Jeff G.
Jeff G.
Marine Mechanic
Vocational, Technical or Trade Scho
4,730 satisfied customers
I have a 1999 9.9 2-stroke outboard ,at slow trolling speeds
I have a 1999 9.9 2-stroke outboard ,at slow trolling speeds it constantly will hesitate and miss.There doesn't seem to be a problem at higher speeds.The plugs are new and the fuel filter is clear .An… read more
Jeff G.
Jeff G.
Marine Mechanic
Vocational, Technical or Trade Scho
4,730 satisfied customers
I have a 1991 200 hp carbureted outboard on a 20 ft.
I have a 1991 200 hp carbureted outboard on a 20 ft. bassboat and I'm now being forced to use gasoline that is 10% or California reformulated. Which jets have to be changed and how much larger or smal… read more
Tan
Tan
MerCruiser Certified Technician
Certified Marine Technician
11,409 satisfied customers
I have a 2003 Suzuki 2 stroke outboard. It has always run great,
I have a 2003 Suzuki 2 stroke outboard. It has always run great, have changed plugs and water pump annually. Recently the engine was run out of gas and now idles extremely rough and quits at idle freq… read more
shane j forrest
shane j forrest
Vocational, Technical or Trade Scho
270 satisfied customers
I have a 2002 Vmax 200hp outboard. Lately, when cold cranking
I have a 2002 Vmax 200hp outboard. Lately, when cold cranking it has excessive smoke. After the engine warms, it decreases. I run across the lake and fish for 30ins, I then crank and the excessive smo… read more
Jeremy R.
Jeremy R.
5,362 satisfied customers
I have a 94 Mercury/Mariner 2-stroke 90HP Outboard. I have
I have a '94 Mercury/Mariner 2-stroke 90HP Outboard. I have not been happy with it since last year's tune-up at an authorized Mercury dealer. I orininally took it in because of hard starting, poor fue… read more
K. Kergan
K. Kergan
Inboard/Outboard Mechanic
Vocational, Technical or Trade Scho
1,031 satisfied customers
i have a 40 two stroke outboard yamaha, it runs but somtimes
i have a 40 two stroke outboard yamaha, it runs but somtimes it bogs when full throtle,and it also skips when idling........could it be dirt in the carb… read more
Jeremy R.
Jeremy R.
5,362 satisfied customers
i have a 2004 mercury 9.9 hp bigfoot 4 stroke outboard that
i have a 2004 mercury 9.9 hp bigfoot 4 stroke outboard that is dropping gasoline in the water. fuel is not leaking from the fuel line or the carburetor (like a stuck needle valve would do), rather it … read more
Jason Forsberg
Jason Forsberg
Outboard Marine Mechanic
Vocational, Technical or Trade Scho
531 satisfied customers
My 1999 Honda 130 @ 4000 rpm will drop about 1000 rpm every
My 1999 Honda 130 @ 4000 rpm will drop about 1000 rpm every 3/4 minutes at cruise. Like it's losing fuel or dropping a cylinder… read more
Larry B.
Larry B.
Marine Service Tech
High School or GED
574 satisfied customers
Evinrude E-Tec engines claim to need NO MAINTENANCE for 300
Evinrude E-Tec engines claim to need NO MAINTENANCE for 300 hrs. How do these compare to 4-Stroke Hondas?… read more
Pappy's Sales and Service
Pappy's Sales and Service
Vocational, Technical or Trade Scho
586 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.

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:

Ted G.

Ted G.

Marine Mechanic

4,145 satisfied customers

40 years experience, Safe boating instruct., Failure Analysis, Expert Witness

Dominick

Dominick

Marine Mechanic

1,009 satisfied customers

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

John White

John White

Marine Mechanic

306 satisfied customers

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

Jason

Jason

Marine Mechanic

24,193 satisfied customers

Degree in Marine Technology. Gas and diesel marine mechanic.

Tan

Tan

MerCruiser Certified Technician

11,409 satisfied customers

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

Jeff G.

Jeff G.

Marine Mechanic

4,730 satisfied customers

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

Noel Schembri

Noel Schembri

Marine Mechanic

3,046 satisfied customers

Advanced technical diploma

< Previous | Next >

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