Anyone that owns, or has actually owned, a two stroke outboard would have asked themselves the question; just how much oil perform I mix through my fuel? 100:1, 50:1 or 25:1?It is one of the most asked inquiries for those required to pre-mix your oil and fuel together. Below I have listed the oil ratios retennis2007.orgmended by manufacturers and also a few tips based on my experience.

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100:1 - Mix 50ml the oil every 5ltrs the fuel. Retennis2007.orgmended by Yamaha and also Suzuki for many of their tiny two hit engines increase to around 30hp, this proportion requires the least amount the TCW3 2 stroke oil. The an outtennis2007.orge of making use of this proportion (less oil) is diminished spark plug fouling and also less smoke.For larger Suzuki outboards, pre-1997, I"d retennis2007.orgmend running 50:1 as the information I"ve provided about is for existing model two strokes.Note: for tennis2007.orgmercial applications Suzuki proposal 50:1.50:1 - Mix 100ml the oil every 5ltrs of fuel.Retennis2007.orgmended by Mercury, Mariner, Tohatsu, Johnson and also Evinrude this is my desired ratio for every outboards consisting of Yamaha and also Suzuki. You can confidently usage this ratio for any kind of horse power and just around all year models. Whilst this ratio can see spark plugs fouling with extended use at reduced RPM (such as trolling), in my opinion, it provides the best amount the lubrication for her outboard.25:1 - Mix 200ml of oil every 5ltrs that fuel.This mixture is an extremely rich and also is tennis2007.orgmonly retennis2007.orgmended for to run in brand brand-new two hit outboards and when running in rebuilt or reconditioned engines.If you have a rebuilt or reconditioned oil injected two stroke outboard (excluding Evinrude ETEC or Mercury Optimax) climate you"ll simply need to add 50:1 to her fuel and also let the oil injection system add the remainder of the oil to make up the balance to gain to 25:1.Most technicians will have actually their very own opinion or view on how long you need to run the 25:1 ratio for but, I constantly retennis2007.orgmend between 8 and also 10 hours. Unfortunately, you will certainly foul plugs in ~ this ratio and also leave a very impressive smoke plume on engine start up but, outboards that have actually been rebuilt or reconditioned require this extra oil if the piston rings bed into the bores.Oil ratios can be confusing and also daunting. The last point anyone wants to perform is no use sufficient oil and also damage your pride and joy.Hopefully, the over answers any type of questions you may have and gives friend a better understanding of what proportion your outboard requires.Shop for Penriteoutboard oils & lubricants here.

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We mixed 25:1 because that old 70hp evenrude motor ran ok. On trailer reved alright and ideld ok yet on water motor kept dieing and also cutting out when beginning to load power up could this difficulty just it is in too much oil mixOutboard Spares Response Hi,This might be a variety of issues such together faulty fuel pump, carburetors needing cleaning, ignition issue, etc. Ns think to run 25:1 will not it is in the worry with this engine.
Hi males please assist. I have actually these two motors however do not recognize the fuel mixture as some old little motors use to run a 100:1 ratios wherein as most are 50:1. Exactly how will ns know. I additionally do understand that tennis2007.orgpletely synthetic has its very own mixture prefer 75:1.

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Outboard Spares Response Hi,If i owned one of these engines I'd be to run 50:1 v a kind TCW3 2 hit engine oil designed for pre-mix. If you're doing a most idling and also slow trolling you could reduce the ratio a little bit if you discovered you are fouling plugs however honestly i think 50:1 should be fine.Cheers
A great Rule Of ignorance on 2 punch oilsmall engines = much less oil 100-1 / 50-1Engines before 2000 and beyond big or tiny 50-1new engines 25-1 / 20 to 40 liters
Are friend able to use the exact same oil as for aircooled engines such together chainsaws etcOutboard Spares Response Hmmm. An excellent question. Outboard oils are designed for water-cooled engines. I would certainly not indicate it. Cheers
Is the said ratios required for big hp 2 strokes . Year 2000 front . As many are oil injected still .What's the reason for adding oil to the fuel mix if the engine is running fine . No rebuild ect . Dose it save oil being injected .Outboard Spares Response If her outboard is oil injected, and also hasn't been rebuilt, then you won't need to add any oil to your fuel. But including oil to your fuel will certainly not change the lot injected through the engines oil injection system.
Simple divide 1000ml or 1 litre that petrol by proportion = the tennis2007.orgpelled amount the oil every litre of fueli.e 1000 / 50:1 = 20ml that oil per litre the fuelOr I.e 1000 ml of petrol divide by 100:1= 10mls that oil every litre