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Anyone who owns, or has owned, a 2 stroke outboard would have actually asked themselves the question; just how much oil do I mix with my fuel? 100:1, 50:1 or 25:1?It is just one of the most asked concerns for those centregalilee.compelled to pre-mix your oil and also fuel together. Below I have provided the oil ratios encourage by manufacturers and also a couple of tips based on my experience.

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100:1 - Mix 50ml of oil every 5ltrs that fuel. Recentregalilee.commended by Yamaha and also Suzuki for most of their little two stroke engines up to around 30hp, this proportion requires the the very least amount of TCW3 2 stroke oil. The result of using this ratio (less oil) is decreased spark plug fouling and also less smoke.For older Suzuki outboards, pre-1997, I"d recentregalilee.commend running 50:1 together the info I"ve detailed about is for existing model two strokes.Note: for centregalilee.commercial applications Suzuki recentregalilee.commends 50:1.50:1 - Mix 100ml of oil every 5ltrs of fuel.Recentregalilee.commended through Mercury, Mariner, Tohatsu, Johnson and Evinrude this is my preferred ratio for all outboards consisting of Yamaha and also Suzuki. You deserve to confidently use this ratio for any type of horse power and just about all year models. Whilst this ratio might see spark plugs fouling with extended use at lower RPM (such together trolling), in my opinion, it offers the finest amount of lubrication for her outboard.25:1 - Mix 200ml of oil every 5ltrs of fuel.This mixture is an extremely rich and is typically recentregalilee.commended for running in brand brand-new two hit outboards and 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) climate you"ll just need to add 50:1 to your fuel and let the oil injection system include the rest of the oil to make up the balance to gain to 25:1.Most technicians will have their very own opinion or see on exactly how long you need to run the 25:1 ratio for but, I constantly recentregalilee.commend between 8 and 10 hours. Unfortunately, you will foul plugs in ~ this ratio and leave a very impressive smoke plume top top engine start up but, outboards that have been rebuilt or reconditioned need this extra oil if the piston ring bed right into the bores.Oil ratios can be confusing and daunting. The last thing anyone desires to do is no use sufficient oil and damage their pride and also joy.Hopefully, the over answers any questions you might have and also gives girlfriend a much better understanding the what ratio your outboard requires.Shop for Penriteoutboard oils & lubricants here.

centregalilee.comments (7)


We mixed 25:1 for old 70hp evenrude motor ran ok. Top top trailer reved alright and ideld ok but on water motor retained dieing and also cutting out when starting to load power up could this problem just it is in too lot oil mixOutboard Spares Response Hi,This could be a number of issues such as faulty fuel pump, carburetors needing cleaning, ignition issue, etc. Ns think to run 25:1 will certainly not it is in the concern with this engine.
Hi guys please assist. I have these 2 motors however do not recognize the fuel mixture as part old little motors usage to operation a 100:1 ratios whereby as most are 50:1. Exactly how will ns know. I also do know that centregalilee.completely synthetic has actually its own mixture favor 75:1.

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Outboard Spares Response Hi,If i owned among these engines I'd be running 50:1 through a decent TCW3 2 punch engine oil designed because that pre-mix. If you're doing a many idling and slow trolling you might reduce the proportion a little bit if you uncovered you room fouling plugs however honestly i think 50:1 need to be fine.Cheers
A an excellent Rule Of ignorance on 2 stroke oilsmall engines = much less oil 100-1 / 50-1Engines prior to 2000 and beyond big or small 50-1new engines 25-1 / 20 to 40 liters
Are girlfriend able to use the very same oil together for aircooled engines such together chainsaws etcOutboard Spares Response Hmmm. Good question. Outboard oils are designed because that water-cooled engines. I would not indicate it. Cheers
Is the said ratios essential for big hp 2 strokes . Year 2000 front . As most are oil injected still .What's the reason for adding 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 hasn't to be rebuilt, then you won't need to include any oil to your fuel. But adding oil to your fuel will certainly not change the quantity injected through the engines oil injection system.
Simple division 1000ml or 1 litre that petrol by ratio = the forced amount of oil per litre that fueli.e 1000 / 50:1 = 20ml of oil per litre of fuelOr I.e 1000 ml the petrol division by 100:1= 10mls the oil every litre