Anyone who owns, or has owned, a two stroke outboard would have asked themselves the question; how much oil do I mix through my fuel? 100:1, 50:1 or 25:1?It is among the most asked concerns for those required to pre-mix your oil and fuel together. Listed below I have provided the oil ratios encourage by manufacturers and a couple of tips based upon my experience.

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100:1 - Mix 50ml that oil per 5ltrs the fuel. Realtoalsimce.orgmended by Yamaha and also Suzuki for many of their small two stroke engines up to around 30hp, this ratio requires the least amount of TCW3 two stroke oil. The result of using this proportion (less oil) is diminished spark plug fouling and less smoke.For enlarge Suzuki outboards, pre-1997, I"d realtoalsimce.orgmend running 50:1 together the info I"ve listed about is for current model two strokes.Note: because that altoalsimce.orgmercial applications Suzuki proposal 50:1.50:1 - Mix 100ml that oil per 5ltrs the fuel.Realtoalsimce.orgmended by Mercury, Mariner, Tohatsu, Johnson and also Evinrude this is my desired ratio for all outboards including Yamaha and Suzuki. You have the right to confidently use this ratio for any kind of horse power and also just around all year models. Whilst this ratio could see spark plugs fouling with prolonged use at reduced RPM (such as trolling), in my opinion, it offers the finest amount that lubrication for your outboard.25:1 - Mix 200ml of oil per 5ltrs of fuel.This mixture is very rich and also is altoalsimce.orgmonly realtoalsimce.orgmended for running in brand new two punch outboards and also when to run in rebuilt or reconditioned engines.If you have a rebuilt or reconditioned oil injected two stroke outboard (excluding Evinrude ETEC or Mercury Optimax) then you"ll simply need to add 50:1 to your fuel and also let the oil injection system include the remainder of the oil to make up the balance to acquire to 25:1.Most technicians will have actually their own opinion or watch on how long you should run the 25:1 proportion for but, I always realtoalsimce.orgmend in between 8 and 10 hours. Unfortunately, you will certainly foul plugs at this ratio and leave a very impressive acting plume on engine begin up but, outboards that have actually been rebuilt or reconditioned need this extra oil if the piston ring bed into the bores.Oil ratios deserve to be confusing and also daunting. The last thing anyone desires to carry out is no use sufficient oil and also damage their pride and joy.Hopefully, the above answers any questions you may have and gives you a much better understanding of what ratio your outboard requires.Shop because that Penriteoutboard oil & lubricants here.

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We blended 25:1 because that old 70hp evenrude motor ran ok. ~ above trailer reved alright and ideld ok however on water motor maintained dieing and cutting the end when beginning to fill power up might this difficulty just it is in too lot oil mixOutboard Spares Response Hi,This might be a number of issues such together faulty fuel pump, carburetors needing cleaning, ignition issue, etc. Ns think to run 25:1 will certainly not be the concern with this engine.
Hi males please assist. I have these two motors but do not understand the fuel mixture as some old small motors usage to run a 100:1 ratios wherein as many are 50:1. Exactly how will i know. I additionally do recognize that totally synthetic has its very own mixture like 75:1.

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Outboard Spares Response Hi,If i owned among these engines I'd be running 50:1 with a decent TCW3 2 punch engine oil designed for pre-mix. If you're doing a lot of idling and slow trolling you can reduce the proportion a little bit if you found you room fouling plugs however honestly i think 50:1 need to be fine.Cheers
A good Rule Of ignorance on 2 punch oilsmall engines = less oil 100-1 / 50-1Engines prior to 2000 and also beyond large or little 50-1new engines 25-1 / 20 to 40 liters
Are girlfriend able to usage the exact same oil as for aircooled engines such as chainsaws etcOutboard Spares Response Hmmm. An excellent question. Outboard oils room designed because that water-cooled engines. I would certainly not suggest it. Cheers
Is the claimed ratios needed for huge hp 2 strokes . Year 2000 forward . As most are oil injected still .What's the factor for including oil to the fuel mix if the motor is to run fine . No rebuild ect . Dose it save oil being injected .Outboard Spares Response If your outboard is oil injected, and also hasn't to be rebuilt, climate you won't need to include any oil to her fuel. But adding oil to her fuel will not change the lot injected through the engines oil injection system.
Simple divide 1000ml or 1 litre of petrol by proportion = the forced amount that oil per litre of fueli.e 1000 / 50:1 = 20ml of oil every litre the fuelOr I.e 1000 ml the petrol divide by 100:1= 10mls the oil every litre