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  1. #1

    Why remove the oil pump vs...

    Let me first say that I have rebuilt at least 8 of these 1200 npv motors now and understand the part about oil lines popping off so no need to just give personal opinions unless you feel like it

    The reason I'm asking this question is more of a theory issue for my particular riding habits.

    I use one of the big ole Yamaha SUVs for fishing. It has the 1200 NPV motor and triple mikuni sbn44 carbs. I am constantly fouling plugs on 45:1 premix due to extensive idle and slow moving time on the water.

    I thought I remember reading a post from one of the amsoil guys saying that Saber Outboard Amsoil is tested safe at something ridiculous like 300:1 but that they drop their claim back to 100:1 to cover their ass. (EDIT: Just called AMSOIL up in Wisconsin and the tech support there vaguely verified this is the case...but that in print it will show 100:1. She said the additive package is so "robust" that it allows for this). If this stuff is truly safe at even 200:1 then why not just leave the ski on the oil pump and then add 200:1 ratio straight into the fuel? A buck or so per 5 gallons to protect a motor in the event of a line, check valve or pump failure won't break my bank. Does anyone do stuff like this and have you ever had a failure of your oil pump or lines that proves the protection? If so, what ratio and oil type do you use?

    Lastly, is it okay to use one type of oil like Mystic or quicksilver full synthetic in the oil reservoir and then another full synthetic like amsoil in the premix? I cant imagine this is an issue but? AMSOIL said they do not recommend mixing oil types like this. They even said not to mix their Saber Outboard and their HP marine due to the lack of knowing what the chemical additives will do when they interact.
    Last edited by macGruber; 10-06-2014 at 09:06 AM.

  2. #2
    ok, it sounds like you already went the premix route with the SUV. why not cut the ratio back to 50:1? make sure your carbs are adjusted correctly and in good shape and you should not be fouling plugs.

    I`ve also run premix for years and never fouled a plug mixing 40:1 with Mystik, Yami2W, Amsoil, XPS etc etc...

    Mystic is good oil. I`ve run their oil for a decent amount of time as well. It is a little smokier than Amsoil but not terribly bad.
    I would use that in a heart beat and save a few bucks to since you don`t have RAVE`s to clean or worry about...

    my opinion on oil injection.
    Mikunin pumps very rarely fail and as we all know it`s the lines or zips/clamps that come loose or shrink...

    If all is "good" new lines, secure clamps weather it be metal tang zips or the newer style Yamaha oil hose clips the systems works. I would just recommend looking at it frequently as you do your pre ride inspection...

    hope this helps...
    Last edited by Pale Rider; 10-06-2014 at 11:07 AM.

  3. #3

    Join Date
    Jan 2006
    Texas City, Texas
    Lubrication requirements vary at different rpms. There are variable injection oil systems on yamaha engines as far back as 1997 that I can remember. At idle, the oil ratio is something like 100:1 (I thought that it was 70:1 but was corrected long ago by someone with far greater knowlege than me). At WOT the ratio is reduced to about 30:1 for greater lubrication.

    There is nothing really wrong with the oil injection systems other than the hoses split or pop off with time. Most folks just do not take the time to inspect these hoses and replace/repair as needed. The results are catastrophic.......combine this with a forum full of guys who typically ride much harder and under rougher conditions than your typical PWC rider. Of course we are going to suggest to simplify and go premix. Premix is worth the hassle for us.

    You should not be oil fouling at 45:1. The synthetics like Amsoil should burn clean for you. Are you running super rich at idle?

    Lastly, it is expected that you would foul your plugs during the engine break in period, but I see no need to add premix (except if you are in full race mode and think that you need extra protection) if your oil injection system is in service.

    The oil manufacturers said that they would not guarante mixing of oils because they had no data to support it..... they did not say that it would not work....only suggested.
    Last edited by salty; 10-06-2014 at 05:37 PM.

  4. #4
    cheatin' piston popper addicted's Avatar
    Join Date
    Jul 2006
    north jersey
    on some of my older skis i actually converted back to injection to clean up the bottom end response and eliminate the smoke. if you are already pre mix running a stock 1200npv i would go with the saber outboard at 100:1. i had around 300 hrs on my raider 1100 when i sold it, probably 200hrs of it with that oil. i still run 2 outboards with it. its good stuff in my experience.

  5. #5
    Mighty Mouse's Avatar
    Join Date
    Feb 2011
    Personally, I dont like pre-mix as it doesn't allow for the difference in oil demand base on engine RPM. If you are idling, you wont need the same amount of oil/gas mix as if you run WOT. Therefore, most premix recommendations are for WOT. Thus making it rich on the low end. PWC riders rarely ride a idle very long and therefore plug fouling is not likely in most pre-mix running. However, if you are trolling and idling for long periods of time your pre-mix is going to be a problem.

    If you put oiler back on and then also add oil to fuel, you may have the same fouling issue. IMHO your best solution is oil pump on, good quality oil, and keep inspecting oil lines. (A 4 stroke is the ultimate solution)

  6. #6
    Banned User
    Join Date
    May 2006
    Last edited by Rocketman; 10-09-2014 at 09:51 PM.

  7. #7
    I dont understand the "too much gas" comment but I am going to take the advice on switching back to oil pump and im gonna go with no extra oil in the tank. The oil lines are 100% replaced, primed and I tested the old oil pump. She is pushing even amounts of oil into each carb throat when tested with a cordless drill. What a PITA putting this all back on LOL. 10 min to remove...1.5hrs to reinstall. Building a shelf long block motor to have on hand using spare parts in caee I blow it again. Im tired of being out of water during good months.

    I agree on the 4stroke comment too! I have a couple fxho donors ready to throw in as the ultimate plan for this Winter. RICHARD!

  8. #8
    Mighty Mouse's Avatar
    Join Date
    Feb 2011
    Oil can foul a plug as most of the oil is not burned off anyway. Rich fuel condition can also cause carbon buildup which techincally is fouling as well. Basicaly combustion temps are lowere that ideal and the tips of the spark plugs gets coated with unburnt fuel or oil. Best to try to tune your low lean, but not so lean as to lean out your mid throttle. I haven't seen many 2 stroke skis that like to idle long periods of time. Although I've had some 2 stroke boat moters idle well for hours. Other solutions would be to try a hotter plug or a different oil.

  9. #9
    Aaah, makes good sense now. Thanks!

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