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Tohatsu 9.8a impeller: and the dilemma of discontinued parts on usable, high quality outboards

Hello everyone.. I just recently got what looks like a mint, most likely unused Tohatsu m9.8A. I've exhausted all of my channels including this forum and all other forums and all other websites across the globe, for any information on where to get an impeller.. I've contacted Tohatsu, the current importer, and I'm trying now to find the Importer during the 80s, which wasn't tohatsu.
Clearly I'm going to have to fabricate an impeller. Not a problem. My question is, has anyone here already done it? I see that a guy was making them seems like three or four years ago but I lost the page. Any help will be greatly appreciated thank you in advance.
 

racerone

Gold Medal Contributor
Yes it is easier to get an impeller for a 1955 Johnson 5.5 HP than some of this new offshore product.------Faced with this situation I would look at the many impellers used today and adapt with either drilling out the impeller bore or sleeving the bore if driveshaft is smaller.-----Post some dimensions off the old impeller.
 
Yes it is easier to get an impeller for a 1955 Johnson 5.5 HP than some of this new offshore product.------Faced with this situation I would look at the many impellers used today and adapt with either drilling out the impeller bore or sleeving the bore if driveshaft is smaller.-----Post some dimensions off the old impeller.

Yes thanks for the reply. Totally agreed. It'll be much cheaper for me to buy a few of the "sierra" impellers and adapt them, stockpile them and then maybe sell a few. rather than tooling and manufacturing. I'll post some pictures when I get it apart and then maybe have my local computer types AutoCAD the dimensions.
 

pvanv

Outstanding Contributor
Scott Lintern (was a member of this forum, I think) from down under, made the then-unavailable M70A impellers. Tohatsu America has since had them made again. Scott was making them on a 3D printer, as I recall. He might be able to make an impeller for you.

As for the M8/9.8A, recall that they were made in the 1980's -- nearly 40 years ago, and the vast majority of those motors have succumbed to salt water corrosion. Fewer and fewer parts are available for those every year. Those were Marubeni imports. Never a large line for them. The M in those models is for Marubeni, BTW.

Once upon a time, when outboard manufacturers made all bits of the motors, parts were available for eons. Nowadays, all motor manufacturers sub out some parts. Carbs from a carb company, electronics from another, impellers from yet another. Then the government gets involved, and forces a new model on us all. The new motors maybe have a different EPA rating or something, and they are a different design. When that happens, the motor manufacturers don't use the same amount of say old-style impellers any more. Instead of selling thousands a year, the subs now sell maybe a hundred impellers as repair parts. Eventually, they sell off all their stock, and once those disappear from the shelves, they are gone forever.

Kind of stinks for those of us in cold, clear, fresh waters, but we are in the minority.

If you can match the side clearances precisely, and come close on the OD, then adapt the hub size, you may be OK. But as for stockpiling, remember that they dry rot on the shelves, and won't be very good for very long.
 
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Good morning Paul. excellent info .thank you for the reply. I really wish I could post pictures of of the motor it literally has zero hours never been in the water. I have spoken with the friendly people at Tohatsu they're going to give me some dimensions, on microfiche! Then it's off to my guys at the cad machine/3D printer. Never giving up. This motor will never see saltwater it will last another 40 years for sure.
Id like to try and adapt something off the shelf first.. I know for sure there is an impeller out there that will fit. Gonna take some research. Its worth it. Got the motor on a trade. Essentially free.
 
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check out karbonwerx on facebook. Might be able to make one for you in urethane.


Thanks for the tip you've been very helpful. I checked out his page for the impeller it seems he doesn't make that part number anymore. 337-65021-0. The trail is getting warmer. I found a few cheap impellers on eBay that I could experiment with that are very close to the dimensions I need. The height of the impeller is the critical dimension. the overall diameter and the inner diameter I can work with by trimming the blades, or boring or sleeving the shaft bore.
 
You sir, are a northeastern treasure. Karbonwerks, an eastern treasure like sia or elle McPherson.. Ordered 3 impellers, paid in advance. "Shrimps are on the barbe mate!"
 
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racerone

Gold Medal Contributor
I believe that there are many impellers that can be adapted.-----Takes time to research dimensions on the many different one.
 

JakeZ

New member
You sir, are a northeastern treasure. Karbonwerks, an eastern treasure like sia or elle McPherson.. Ordered 3 impellers, paid in advance. "Shrimps are on the barbe mate!"
Hello... I also have a pretty much mint condition 9.8A. It's like a showroom piece. Runs great, but I also have had trouble finding an impeller. Did you end up finding a source or fabricating any?
 
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