Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: 1989 Yamaha 200hp overheating

Posted by Gil on 10/06/15 - 4:47 PM
#1

Looking for some advice as to why my 200hp 1989 yamaha outboard is overheating while running it with the rabbit ears
Needle rises after about two min. Then alarm sounds any clues to why it's doing this I just bought the boat couple days ago it runs fine in the water without over heating



(changed abbreviated year to full 4 digit year for clarification and following our guidelines)

Edited by Joe Kriz on 10/06/15 - 4:49 PM

Posted by tedious on 10/06/15 - 5:15 PM
#2

By "rabbit ears" do you mean earmuffs? If so, then the answer is simple - you are not getting enough water flow to cool the motor. Turn up the hose or figure out how to have the muffs seal better to the water inlet. Do not continue to run the motor on the muffs until you fix this problem, or it may become new motor time.

Tim

Posted by Gil on 10/06/15 - 5:23 PM
#3

Hi Tim yes I'm referring to earmuffs the motor is spewing out a nice strim so I don't understand how it could be overheating

Posted by flippa on 10/06/15 - 6:22 PM
#4

Do you know if the water pump has been changed recently?

It might be time to change it out; it's not a very difficult job and doesn't require any special tools. There are several step by step videos on YouTube if you choose to do it yourself.

I change my water pump out every other year, so I would definitely recommend it.

Posted by Gil on 10/06/15 - 7:30 PM
#5

Flippa yes it was just services and there's a strong stream of water

Posted by JRP on 10/07/15 - 4:04 AM
#6

My 1992 Yamaha 150 is the same engine as yours (2.6L V6) and the overheat alarm will go off when flushing with the muffs also. With my engine, on the muffs it takes about 10 minutes or so for it to heat up enough before the alarm sounds.

The alarm never sounds during normal operation when running the boat.

It could be that these engines simply don't cool as well with the muffs as when they are in water. They are also getting pretty long in the tooth at this point, so the cooling system may not be everything it was originally. There may be a small amount of build-up that is impediing circulation of cooling water to certain parts of the engine when the water supply is not optimal (muffs).

You could try a product called "Salt-Away", which supposedly will help to dissolve salt and other deposits impeding the circulation of cooling water. A mechanic can also open it up and physically clear/clean the cooling passages, but I don't suppose that would be a cheap option.

Posted by gchuba on 10/07/15 - 5:08 AM
#7

Just last week as a guest and helping with the clean up, the owner had earmuffs that supplied water to both sides of the motors intake. I originally picked up earmuffs with water to one side only and he had me swap them out. He runs 225 hp Yamaha OX66. No alarm.
Garris

Posted by mtown on 10/07/15 - 5:16 AM
#8

I have a 200 Yamaha of the same age and when I am running it on a lift I have to lower the motor well past the intake ports to get it to pee properly. My other Yamaha motors only need to get in as far as the intake ports.