Propeller 3ym30 Sillette outdrive

[Bradley]

I just repowered with a Yanmar 3YM30, 2.62 gear ratio. I have a Silletee Sonic outdrive with a 1:1 ratio.

I did a sea trial with a 15 x 12 3 blade prop. The results:

All speeds are GPS over ground in knots. Water was calm but wind was high.

RPM with wind reciprocal course

2400 5.3 3.4

2800 5.7 4.0 to 4.7

3000 6.1 5.0

3200 6.5 5.1+

3400 6.7 5.6


Maximum rpm was 3700. Maximum rpm in neutral was 3900.

Two questions: What do you think my other prop should be. Where can I buy these props in the US. It is 17 spline on a 28 mm shaft. Apparently, it is also used by Yanmar and Volvo.

[vinsondynes]

I have a prout 37 snowgoose and have just purchased a y
3 ym30 to replace the old 3gm
Im planning on getting to it as soon as the weather gets nice in Annapolis end of march 2014
has anyone done this refit , I'm looking for advice
Vince
looking for advice

[atoll]

some good info here, from sillette,the makers of sonic drives


sillette_downloads_page

[Bradley]

Very easy retrofit. Mounting brackets are different so you need to patch old holes and drill new ones. Other than that you may need a new adapter from transmission to out drive. Call Sillette with any questions.

[vinsondynes]

Well the engine swap was easy
As it turns out the footprint and mounting are identical for the old Yanmar 3gm20 and the new 3ym30f
I did have to remove the exhaust interexchanger log,exhaustelbow,alternator,fan belt shroud,and motor mounts to get it in the hole but a chainfall hoist from the boom (this was supported by the main halyard directly above the load and moved twice as the engine was picked up from the ground quite far down the boom )
It fit exactly where the old motor was
Now i need to determine props and hope to get a us supplier
Sillette has recommendations for old style 14" props or suggest the option of upgrading to a new 17 spline shaft with a 15" prop
Any suggestions from owners on which props they have?

[vinsondynes]

What was your final result
Did you find props available here at a reasonable price or did you buy from Silette
I would like to find props available here in north america if possible


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[Boatguy30]

You have that on a lagoon? 3700 rpm is just about right. You need to be able to get full RPM with the boat fully loaded you're pretty close I'd guess. Prop seems fine

[vinsondynes]

It is a Prout 37 Snowgoose with a Sillette not a lagoon
I'd be really interested in any spares that someone out there might have for sale


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