Overheated Outboard due to Plastic Bag

JRock80

Cadet
Joined
Aug 2, 2018
Messages
6
Looking for some help. I have a 2005 Johnson 90 hp 2 stroke. Last weekend leaving the canal or entering the bay I picked up a plastic bag. Once I got into bay I started to increase speed. Once I reached 2500 rpm’s the motor started to shake and wouldn’t allow me to go any faster, so I backed off throttle and seemed to run fine, then I noticed the engine was overheating so I stopped and shut off outboard. I raised the outboard up to make sure I didn’t snag something. That was when I noticed a plastic trash bag next to boat. Now the outboard is still stuck in limp mode. Has this happened to anyone? What did you do to fix issue or recommend me replacing? I plan on replacing water pump, thermostat and sensors first, to see that corrects issue. Open for suggestions and guidance, thanks for your help in advance.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
52,029
The bag stopped water flow and 10 seconds later the impeller melted.

Pull the lower and replace the water pump
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
14,129
Do a compression test too, engines that overheat often scuff/score the cylinders. Common problem, I hope whoever throws garbage into a body of water has that happen to their engine
 

Jamull2852

Cadet
Joined
Jul 27, 2018
Messages
17
Do a compression test too, engines that overheat often scuff/score the cylinders. Common problem, I hope whoever throws garbage into a body of water has that happen to their engine

how bad do scuffs/scores on cylinders affect the performance? One of mine has scuffs compression is still within range.
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
14,129
how bad do scuffs/scores on cylinders affect the performance? One of mine has scuffs compression is still within range.

The secret word is "still". and while that compression reading is "within range" at cranking speed, what exactly is the 'range'? Very few engine makers publish a spec.
 

Jamull2852

Cadet
Joined
Jul 27, 2018
Messages
17
110 on the scored cylinder, still troubleshooting the over heating issue. the rest of the cylinders are around 115
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
14,129
This will save you a lot of time, money and frustration... You powerhead is damaged, it needs at least one cylinder rebored, the remaining may get by with a honing. To do it right, new pistons and rings all around. Heads checked for warpage, and lapped or replaced as required
 

R DAVIS

Seaman Apprentice
Joined
Aug 12, 2012
Messages
34
If you have insurance coverage on the boat / motor (Physical damage coverage, not just liability) Stop now and call your insurance claim department. Don't accept an answer from your insurance AGENT that plastic bag overheat is not a covered peril. Agents seldom know about perils regarding boat coverage. If you don't have insurance on it, you're on your own, if you DO, let them handle it from the get go.

Good Luck.
 

Bosunsmate

Admiral
Joined
Apr 7, 2012
Messages
6,135
Many outboads ive run have scored walls, dont fret if you dont have insurance, just replace impellor and see how she runs, she could do another 40 years fine
 
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