89 merc 115

[farlee308024]

Hi everybody I am new to the site. I have some problems with my 1989 Mercury 115. I took it out for my first time (just bought the boat). It started right up left it running while wife took the truck/trailer to a parking spot it was about 5/10 min?s when she got back. We took off from the boat launch and for about 45 min?s the boat ran fine. Then I got what I believe is the overheat alarm on my remote because the oil injection system is still active and the oil tank was still full. There was little to moderate stream coming from the engine. When I got home from the lake I hooked up the muffs to the engine and now no water I had the hose on full blast and to make sure there was no issue with the hose/muffs I lower the motor in my dunk tank and tried it again for about 30 seconds and no go.

So here are my questions
-I guessing, I?m going to have to rebuild my water pump Correct?
- What else should I replace when I do this?
- How would I check psi on the motor?
- When I checked the oil tank there was a large sucking sound when I released the cap. Should I invest into a new oil cap?
- What are your opinions on the oil injection systems on mercury?s?
-I know this might sound stupid I just want to make sure it?s the overheat alarm and not the low oil alarm. It?s just a constant beeping, I have only own Evinrude motors before and they had horns.
-I also forgot the alarm will not shut off and it has been two days

 

[farlee308024]

Re: 89 merc 115

Bump!!!!!!!!!!!! I know I'm shotguning the question but I do need some help here

 

[BatDaddy1887]

Re: 89 merc 115

Sorry to hear you're having trouble. As far as the oil injector, most people think that they are a dangerous item to have connected to an outboard engine 'cause they can fail and destroy the engine. I took mine off and just mix up 50/1 oil directly into the fuel tank like old times. This method is safe and you know you're always getting the right mixture in your fuel.

Your other problem sounds like you may have gotten mud or sand in your water intake ports in your lower unit (where you hook up the muffs)...just a guess since it took awhile after launching. You may have completely fried your impeller if the engine ran for more than 15 seconds without water. You need to drop the lower unit (7 or so bolts) and change that out (only about $15).

PSI on your cylinders should be over 100 psi per cylinder using a compression checker (screws into the spark plug hole and has a gauge on the other end of the hose, do a check on each cylinder and make sure they are within 15 or so psi of each other). Good luck.

Jim

 

[Ware5150]

Re: 89 merc 115

I agree, I would drop the lower unit and inspect the water pump. A rebuild kit is cheap and easy to do. One thing on mine was a small connection tube. This tube connected the water pump to the hard line into the block. This had come off therefore not pumping water anywhere but back out the lower unit.