97 Gts mixed 2 different oils.

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Joe Go

I have a 97 GTS I just bought recently. I mixed the wrong oils TC-w3 multipurpose 2 stroke Valvoline oil blue bottle, mixed it with Pennzoil synthetic blend (big yellow bottle) XLF TC-w3 NMMA. Marine engine extended life formula. It had about a 1/4 of tank oil of the Valvoline and I added another 1/4 tank of Pennzoil. So 1/2 tank total. Ran it on a full tank of gas. It ran great until last run. Started bogging a lil bit. I know I have to drain all the oil out of the tank and need to use synthetic oil only for the 717 engine. What else should I do after I drain all the bad/mixed oil out? Before filling the tank back up? Let me know if you can help? Or anyone else reading this forum. Much appreciated. Joe Go
Pics of the oils I mixed below


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The wrong oil will not cause the engine to run funny by itself. The wrong oil can gel in the filter and starve the engine from lubrication which can cause it ti seize and bog out.

To replace the wrong oil you need to get the old oil out by siphoning or draining the oil tank. Clean out the tank. Suck the oil out of the rotary gear cavity and install a new oil filter. Then you can add the correct oil and bleed the oil pump with the bleed screw until clean new oil comes out then start the ski and at an idle hold the oil pump arm wide open until the new oil gets to the intake manifold and you are done.
It only only bogged a lil bit coming in on last run when bringing it in to trailer. It might of been low on oil already so that's what I think caused this. I will try what you said thanks for your help. Also quick question. Do i need to add any gas into oil tank at all? Before refilling to make sure all the old mixed oil, will clean out properly when starting again?
I like to pull the tank and clean it out with gas to make sure everything is clean.
You are the man thanks been looking all over these forums for a simple mistake I made. Wanted to fix the mistake properly with out any further damage. A couple of guys on the other forums and sites were like never mix them. But never gave any solutions of what to do if you did, what i did.
Is the Pennzoil synthetic ok to use for my ski?
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