Hunter 34 Transmission fluid?

May 16, 2021
39
Hunter 34 Melbourne, FL
I recently purchased a 1985 Hunter 34 with a 3GMF engine and the transmission is Kanzaki KM3-A and the plate (attached pic) says SAE OIL, but when I checked the dipstick the viscosity was very thin and looked like Transmission fluid. There has been no transmission issues, goes into forward and reverse without any delay or issues. What should I do? My concern is am I borrowing trouble to suck out the fluid and replace it with oil? I have no clue how long it has been in there. Any suggestions would be appreciated.
Rob
 

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Oct 22, 2014
20,995
CAL 35 Cruiser #21 moored EVERETT WA
I recently purchased a 1985 Hunter 34 with a 3GMF engine and the transmission is Kanzaki KM3-A.......suck out the fluid and replace it with oil? I have no clue how long it has been in there.
I suggest it would be best to know your starting point. Yes suck out all of the fluids on the boat and put in your own products. You will then know what tis in the engine, where you can buy more if your need to, and create a log of when the fluids were serviced on "your boat".

SAE OIL - This is a catch all phrase. Your transmission fluid is an SAE - Oil. Check your manual for the specifics on viscosity. Do the same for the oil in the engine.

While you are at it do the zincs in the heat exchanger.

It is fun owning a boat. Welcome to the SBO Forum. Congrats on your new boat.

Oh... One of the neat features here on the forum is the search function... Just found this discussion from 2016. It appears to be on point.
 
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Likes: Andiamo 34
May 16, 2021
39
Hunter 34 Melbourne, FL
Thanks for the help, just didn't want to create a problem where there currently was not, but I know the best solution is to use the reccomended. Happy sailing.
 
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Likes: jssailem
Nov 6, 2006
9,885
Hunter 34 Mandeville Louisiana
The Kanzaki needs straight 30 wt engine oil, not multi grade (as in 10-40 etc) It only takes around 300 cc (10 fluid ounces) of oil, so a quart is plenty.. A quart is 32 ounces. The premium oil stuff is fine, Shell, Mobil, Pennzoil, etc. Don't worry about the API service ratings, you'll probably find "SN" . Running with the ATF in it in the short term won't hurt it but ya want to change it soon.
Downloads (sailboatowners.com)
And under " Owner Resources" , click on BY BRAND and Hunter 34 ..
 
Jan 4, 2006
6,444
Hunter 310 West Vancouver, B.C.
Being too lazy on my part to look up the specs for a Kanzaki KM3-A, I would go by the plate info and use 20W-30 diesel crankcase oil.

Transmission.jpg


However as you so rightly pointed out, who knows what will happen when you mix the new with the old, so drain and refill several times over with 10W-30 and run the engine IN GEAR for a few minutes between "rinses". Remember to tie the boat to the dock :banghead:.

If you're OCD like myself, then take it out and run with WOT for a few minutes and change one last time.

As @jssailem has suggested, replace ALL of your on board fluids so you know where you are starting from. No telling what's in there.

Please be advised that some of the dumbest life forms on earth are previous boat owners so there's no telling what you've got in there. Be particularly careful when you change the antifreeze if you are going to a different type. Check the archives here to see what to look for. Again, use the "rinse" method if the old and new are dissimilar however in this case "rinse" with plain water several times.
 
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Likes: Andiamo 34
May 16, 2021
39
Hunter 34 Melbourne, FL
Thank you for the support and I will be cahning all the liquids as I don't think there was much TLC over the last couple years.
 
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Likes: jssailem