Oil injection or mixed fuel???

[fordfan1]

I have a 2004 ox66 i just bought and was wanting some opnions on leaving the oil injection on the motor or mixing the fuel. I heard it would cause problems with the O2 sensor if it was removed, and start having other engine issues with out the oil injection. Any one experience problems?

[Reel Insane]

Leave it as is.

I have a 2006 150 TXR which is oil injected and have had no problems with the oil injection system. I would advise you to leave the oil injection system alone and run the boat as Yamaha had intended. Why take the chance of your oxygen sensors or anything else not working correctly. I am a firm believer in if it is not broke do not fix it. Especially if everything works fine now.The only thing I would advise you to do is to keep a quart of oil on your boat at all times. I have run into a small problem once when I did not check the oil before I left out. I made it back safely but, have started keeping a quart on board just for peace of mind. I always check my on board oil tank before I leave out since then.

[Tucker]

Get rid of it, premix and have piece of mind. Or, search the forums for oil pump problems and make your own decision. You won't go through many pages without finding someone that has an issue with their oiling system. "If it aint broke don't fix it" Problem is when that system breaks, you may be shopping for a new motor.

[Aleutianwest]

pre mix

You dont want to premix a fuel injected motor you will kill your injectors

[Tucker]

Sorry, that's incorrect. Done it with OX66. Use good oil & Ring Free no problems. Keep an eye on the 02 sensor; mine was always in good shape, even the barbell. I think Ring Free is the secret. Run a 2-micron fuel filter and you'll never have to open the VST. Lay it up with treated fuel or you'll be hatin' life. Has Ethanol gas made it to Alaska yet? If not, get ready for a nightmare. That on top of those 6' tide swings you folks have.

[rodbolt17]

its kinda idiotic to disable a very very good system.
why not simply maintain it and run it as designed.
I am a master tech for yamaha.
been doing this almost 25 years with it.
since the introduction of the mikuni pumps about 1990, never seen a pump failure related engine failure.
most techs that blame oil are simply wrong, the rest dont care.
2 micron is way to restrictive and NOT reccomended for outboard use.
disiel yes, not gas outboard.

[Tucker]

Ah, Rodbolt you have bailed-out many of us weekend hacks with that 25-years of experience; and I can't tell you how much we appreciate it. Problem is, things that would catch your eye often get missed by us laim-brains. I read about 1-guy that lost a cyl because the oil feed hose going into the intake manifold cracked at the nipple and leaked. Another guy got water in through the remote fill and blew his engine. The builders stuff the tank in some remote area accessable through a 12X12 hatch. How often is that pump filter going to get changed by the big old guy? Great system, just a bit high maintenance for the average joe. Like many things, if the maintenance is difficult, it won't get done. Do you have many customers that ask to have their oil feed system serviced? Most guys in my marina think they only have to do something when the buzzers go off.

[99yam40]

If you do not do the service Yamaha or any other motor manufacturer recommends then it is not their fault. It is like not ever changing the oil in your truck or auto until it craters or the oil light comes on, just not the way to do things.
Heck my father years ago called and said his farm truck had a bad oil leak, I checked it out and the oil filter had a hole rusted through it. It burned oil bad so he just kept adding oil instead of changing it and the filter, I wonder why the motor burned all that oil.

Do the maintenance and run it like it is meant to be run

[catmandon't]

Oil requirements vary with RPM, what mix would you run. I would maintain the system and use it.

[200090tlry]

You could run 50 to 1 without a hassle

At idle your plugs will foul but being a yammi I bet it keeps running fine. My force/mercury called out 50-1 premix was not greatest idler but then again only had one carb for 3 cyls could never dial it in perfect.

[rodbolt17]

on a steady diet of cleanly PROPERLY mixed 50/1 that OX66 will be happy.
the issue is we aint mixing 6 gallons at a time in a remote tank for a 14ft tinny.
mixing 100-150 + gallons at a whack gets very difficult.
thats why all outboards above about 100 HP and 2stroke are pretty much oil injected.
the manufacturers are trying to prevent the consumer from screwing up.

granted there is and always will be the guy that can take a rubber hammer and an anvil and bust the anvil.
just the way it is.
maint is simply maint.
do it or the machine dies faster.

[BQUICK]

Rodbolt:
What was the problem with the pre-Mikuni pumps? I've got em on my 1989 200s.

[rodbolt17]

no real issues, occasionally the check valves would fail.
other than the pre mikuni (Kien) pump isnt avalible anymore and hasnt been since about 1990.
the pumps dont have much offered for parts but the Kien can be dissasembled and cleaned.
if a check valve is damaged I remove all six valves and add six inline valves from the mikuni type system

[BQUICK]

Would it make sense for me to add the inline check valves to mine even without touching the ones in the pump?

I usually go by: if it ain't broke..don't fix it.....but sometimes it pays to play with something.

[Reel Insane]

As I read through the posts I started to laugh at all the responses. I did get a bit excited over the “if it is not broke don’t fix it” response. I am a firm believer in leaving things alone if they are not broke. On the other hand I am a big advocate on upgrading individual systems if it will improve overall efficiency of the whole engine. I applaud Fordfan1 for asking the question in the first place. Asking questions and getting multiple responses allows an individual to research better about the decision being made.

Since we are throwing out professional credentials I will throw mine out. I am an ASE certified Master Diesel Technician and have been for 10 years now. I am a newcomer to the outboard engine world (for the past 4 years now) and so far have been enjoying it. I am not a newcomer to boating as I have been in and around the water my whole life. I practically lived on my father’s 57’ custom sport fish.

Another item that concerns me is the fact that someone stated that a particular item is more high maintenance than the rest of the engine and gets overlooked or not maintained. I agree that the engines being manufactured now days do require more maintenance than they did in past years (even though manufacturers are trying to make engines that require less maintenance). In my opinion it is the owner’s responsibility to research and keep up with all maintenance aspects of their vessel. On the other hand it is also the dealer’s responsibility to properly inform the new owner of the type of maintenance that needs to be performed and when that service needs to be done.

I believe the number one cause of premature engine failures is not the design of the engine but the maintenance that engine receives. Every engine needs a visual inspection on a routine basis. If that is performed the dry rotted/cracked hoses and other defects will be identified and once again left up to the owner to correct.

Fordfan1 keep the questions coming, as asking questions and research combined will keep you on the water longer and hopefully out of the shop.

In the words of Tred Barta
“Till next Tide”

Reel Insane