Notices
The Boating Forum
Like Tree5Likes
  • 3 Post By brownman
  • 1 Post By DonV
  • 1 Post By brownman

90Hp Mercury Optimax NEED HELP

Old 08-17-2019, 10:58 PM
  #1  
Junior Member
Thread Starter
 
Join Date: Aug 2019
Posts: 1
Default 90Hp Mercury Optimax NEED HELP

What's up guys,

I have a 2010 90 Hp Mercury Optimax 2 stroke outboard that is starting to give me trouble. This boat was given to me 2 years ago by my uncle, who had a mechanic maintain it over the last 8 years Recently on the past two runs we had the engine would bog down and lose a sufficient amount of power, out of nowhere the power would return but then it would be lost just as quick. We thought it was maybe it was some water in the fuel so we put in some starton in the but the problem persisted. The engine started fine, but never got enough power to come up on plane and the engine continued to stall out several times on the way in. We are guessing it is a fuel issue but we are not sure on where to start. I can't seem to find a water seperator on this boat,It's a 2010 Bayliner, Any help is appreciated, Thanks, Guys!
chris90hp is offline  
Old 08-18-2019, 03:23 AM
  #2  
Senior MemberCaptains Club Member
 
Join Date: Mar 2004
Location:
Posts: 366
Default

Check your fuel lines. Sometimes the inside part of fuel line collapses and robs the engine of fuel. Then check fuel pumps
limitman is offline  
Old 08-18-2019, 04:24 AM
  #3  
Senior Member
 
Join Date: Apr 2009
Posts: 566
Default

Well if pouring in starton didn’t fix it it’s time for a new motor!!!!!
sjef, DonV and El Comandante like this.
brownman is offline  
Old 08-18-2019, 04:42 AM
  #4  
Admirals Club Admiral's Club Member
THT sponsor
 
Join Date: Apr 2013
Location: Baton Rouge, LA
Posts: 5,550
Default

Ignition coil.
davidwademarine is offline  
Old 08-18-2019, 07:58 AM
  #5  
Senior MemberCaptains Club Member
 
Join Date: Jun 2003
Location: augusta, ga beaufort, sc
Posts: 688
Default

Run it on an 3 gallon external tank and see if quits bogging (don't forget to add some oil to the gas, not sure how the optimax mixes gas/oil). Squirt some of your fuel into a mason jar and see if you have trash or water in it. That will eliminate fuel contamination and/or delivery issues, from the tank anyway.
drumbeater is offline  
Old 08-18-2019, 08:02 AM
  #6  
Admirals Club Admiral's Club Member
 
Join Date: Apr 2012
Location: West Coast of Florida
Posts: 296
Default

Originally Posted by brownman View Post
Well if pouring in starton didn’t fix it it’s time for a new motor!!!!!
NO doubt!! He should have used StaBil 360 and I'm positive he would have had success!! Or the ever famous Seafoam would have fixed that coil!!
brownman likes this.
DonV is offline  
Old 08-18-2019, 09:46 AM
  #7  
Admirals Club Admiral's Club Member
 
Join Date: May 2018
Posts: 99
Default

Check the filter in vst and see if any junk in there. Also check fuel/air psi on rails and see what those are.
Eightpter is offline  
Old 08-18-2019, 11:12 AM
  #8  
Senior Member
 
Join Date: Aug 2016
Posts: 980
Default

First thing invest 150$ and get a good racor filter setup and new fuel lines.Its a Boat and will get some water accumulation in the tank. and since the water is heavier than fuel the first thing headed down stream is the water. and fix the coil
nevets is offline  
Old 08-18-2019, 11:19 AM
  #9  
Senior Member
 
Join Date: Feb 2016
Location: Southeast Tx. Goodrich
Posts: 484
Default

Check your battery and wiring. All connections. Check battery voltage. These are power hungry engines. Make sure battery is at least 1000 cca.
Fishman39 is offline  
Old 08-18-2019, 01:56 PM
  #10  
Senior Member
 
Join Date: Apr 2009
Posts: 566
Default

Pics of the wife!!!!!
El Comandante likes this.
brownman is offline  
Old 09-18-2019, 02:27 PM
  #11  
Member
 
Join Date: Jun 2016
Posts: 74
Default

Try to hook up to a separate small outboard fuel tank and run it. My Optimax 225 has a mixture of 100:1, so I'd think yours maybe the same. Also, replace all fuel and oil filters to see if that improve. Seafoam is good to clean the engine, but only use it in a separate small fuel tank.
stevechumo is offline  
Old 09-19-2019, 04:50 AM
  #12  
Senior Member
 
Join Date: Feb 2016
Location: Southeast Tx. Goodrich
Posts: 484
Default

Originally Posted by stevechumo View Post
Try to hook up to a separate small outboard fuel tank and run it. My Optimax 225 has a mixture of 100:1, so I'd think yours maybe the same. Also, replace all fuel and oil filters to see if that improve. Seafoam is good to clean the engine, but only use it in a separate small fuel tank.
Dont premix an opti. Bad things happen.
Fishman39 is offline  
Old 09-19-2019, 03:20 PM
  #13  
Member
 
Join Date: Jun 2016
Posts: 74
Default

Originally Posted by Fishman39 View Post
Dont premix an opti. Bad things happen.
That's good to know.
stevechumo is offline  
Old 09-19-2019, 03:34 PM
  #14  
Senior Member
 
Join Date: Apr 2011
Posts: 3,183
Default

Originally Posted by Eightpter View Post
Check the filter in vst and see if any junk in there. Also check fuel/air psi on rails and see what those are.
Tons of good info in this thread. But, first things first. See bold print above.
Ifishalot is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.