30 hp auto lube converson

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30 hp auto lube converson

Post by Bonglebust40 » 30 May 2018, 10:16

Hi guys I've got brought a 30 hp 3 cylinda 3 carbs yamaha 2 stroke...but the only problem is it's a long shaft not a short shaft
I have a honwave t40 and was wanting to get it converted to a short shaft dose any one know how I can go about getting it done many thanks

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Andy B Great Britain
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Re: 30 hp auto lube converson

Post by Andy B » 30 May 2018, 16:50

Do you know which year and model?
If it has the insert in the leg then yes it is possible, but there are a couple of thing you need to be aware of first.
Firstly, are you actually able to remove the extension from the leg? There's usually plenty of corrosion around the bolts due to the fact that they will never have been undone before.
Secondly you'll probably have to find a short shaft gearbox or strip the long shaft box and replace the drive shaft with a short one.
The water pipe will have to be shortened or changed as well.

Yes it is possible, but it's probably easier to change the engine for a short shaft one.

If you've got 20 minutes to spare, here's a video i made about converting a long shaft Tohatsu 3.5hp to short shaft.
It's not completely relevant to your OB, but it will give you an idea about what's require.
Hope it helps...

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Re: 30 hp auto lube converson

Post by Paul » 30 May 2018, 23:00

Agree with all of Andy's comments :thumbsup
Providing you can source the shorter parts required as per his video .........
The lower section of the spacer/extension casting should come apart relatively easy if the OB has been serviced having had the impeller previously changed ...... it's the upper housing bolts/faces that'll be corroded :idea:
If you soak the retaining bolts with a releasing agent like WD40 or diesel over a good few days prior to working on the bolts and mating faces you might give yourself a better chance of separation :idea:
If the bolts/mating faces are proving difficult to un-do/seperate then I'd apply heat to the the area, not excessive heat but good and hot then apply the releasing agent as a 'cooler' to entice penetration into the threads/faces a few times :idea:
It may well take lots of time and patience to remove corrosion of the bolts and again seperating the housing ;-)
Do not apply the releasing agent whilst using a blow torch or heat gun obviously :!: :stop :no

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