Oil injection VS pre-mix ( pros & cons)

[ADKMATE]

I'm considering doing away with the oil inj on my 115 yamaha 86'. As far as I know It works fine. At the end of last season I put a new powerhead on and as an extra precaution I was thinking of going the pre-mix route. It would also free up some storage space for me. Is there anything I should know about disabling the oil injection system? Its the type with the main tank mounted on the motor and a large reserve tank mounted in the boat.
Thanks

 

[Chris E]

how are you going to plug all the holes from the pump to the carbs and top bearing?

 

[ADKMATE]

Thats what I'm trying to find out. I'm not sure what needs to be done to unhook the oil inj. A good number of folks on this sight have done it from what I've read. Hoping someone could point me in the right direction.

 

[JK86 Starflite]

I am getting ready to do the same to my '86 Black Max 200. I found this website on another thread. Give them a call, I'm sure they have a kit for your motor. cheers
JK

http://www.rickracers.com/product_info.php?products_id=3536

 

[Chris E]

if i'm not mistaking, the merc set up mixes fuel and oil at the fuel pump whereas the yamaha set up mixes at the carb i remember there being a ton of individual oil lines coming off the yamaha pump. if it's working leave it alone, its a brass gear on the crankshaft and metal on the pump so it's pretty durable set up.

 

[F150GT]

Chris your correct about the way the oil is introduced into the fuel, Yamaha has multiple lines going to each intake runner. If your really hell bent on removeing it you could plug all the individual lines and remove the pump, not sure if you need a block off plate. Yamaha oil system is reliable, I wouldnt remove it. I'v had 6 older Yamaha's and no oilling problems --knock on wood--.
For the record you Merc guys with older motors should check the condition of the oil lines on your motors regularly, I'v found several that the lines were hard and brittle and would breake withought notice. No more oil. Give them a tug & a twist, see if they are soft and plyable.

F150GT

 

[Chris E]

--.
For the record you Merc guys with older motors should check the condition of the oil lines on your motors regularly, I'v found several that the lines were hard and brittle and would breake withought notice. No more oil. Give them a tug & a twist, see if they are soft and plyable.

F150GT

my next door neighbour found out about that the hard way - $5000 later.

 

[F150GT]

My buddy got lucky, he noticed oil dripping out when he was getting ready to back it in the water.

 

[ADKMATE]

Thanks for all the feedback, I've decided to leave the oil inj on. I have the shop manual so I'll go thru the test procedure, make sure its working right and leave it at that.

 

[Eluder]

oil injection

The main thing you need to check is the Pump GEAR it's a nylon drive gear on the crank shaft of the engine if it is an older one the gear becomes brittle and the gear teeth start to chip off and the pump starts to slip. (the pump drive gear is metal- bad design) But the alarm should sound-maybe you might hear it over all the noise as your engine starts to slow down... I removed the pump when I installed a N.O.S. Powerhead. No worries now....