Classic Australian Wooden Power Boat Association

Hi Phil, (no pun intended}
I called him a few months ago. No answer so left a message but haven't had a rely. Don't know what's going on.
Bob

Thanks Bob for the reply.

Hi Phil /Bob
Yes sorry about the lack of response - been very slack plus a couple months R&R in WA
Not much progress with Buster I have accumulated most of the parts I need plus machined offset adapters for the SUs
A couple of questions you guys may be able to help with?,
- as per previous post I intend to use the Holden engine - when I check the location of the engine in the boat using the exhaust manifold and pipe which come with the boat ( relatively accurate positioning fore - aft) it doesnt any where near marry up to the prop shaft.
Maybe the exhaust system is not from Buster? alt the prop shaft is not ? Any ideas? ( Phil)
- also Bob warned me a suitable Prop may be difficult to find - any suggestions ? What size - where from ?

Great to here from you I would line the motor up with the prop shaft and then do the exhaust you may have to change the exhaust a bit it is the system I got with the boat using rubber allows for alignement issues a bit and you can redrill the transom to suit as there is not a hole in it or put them over the deck looking forward to seeing some photos down the track good luck Phil

As for a prop someone on here may have one I would think as a start around a 9.5x 14 the diameter will depend on the clearance on the bottom its a shallow skeg Lunberg in Sydney still make 2 Blade props to my knowledge hope this helps Phil

Thanks for info Phil I will check out Lundberg
Maybe I should attack the engine location from 1st principles -
1) is there a such a thing as the 'optimal location' for the engine in a Skiff? I have some room to move - the prop shaft is located but length could be easily altered - engine is dry sumped and timing case drive so very low / close to the gland is possible
2) I think Bob mentioned that the distance from the skeg to prop boss should be 1 1/2 times shaft diameter is this standard practice? ( hope Im not misquoting you Bob)
3) I will probably run the exhaust over the deck - assume zoomies are out due to legality issues, so so 6 into 1 - or 3 into 2 into 1?
How do you prevent cooling water migrating to the head if the exhaust ports are lower then the deck?
Its obvious 'I dont know what I dont know' so better to ask the naive questions before blundering on

The distance from the skeg is right no more than 1 1/2 times the shaft diameter and put the water into the extractors near the end you can run zoomies if you want but pipes are better I think Phil

Hi Kevin,
Good to hear from you again. Couple of things ............
* Regarding engine positioning, rule of thumb is as far to the rear as possible, leaving room under the sump at lowest point for flex of the hull when you hit a wave. Maybe 12mm at lowest point.
* Lundbergs are no longer in Sydney. The sons have a place near Berry on the South Coast. Last time I called them, they said they were now only doing 3 & 4 blade ski props. Cassells may have a second hand prop, could try them. Also call Steve Moritz in South Oz.
* One failsafe method I've seen of water to quite the exhaust (who wants to do that anyway) is to have an external steel/copper pipe strapped to the exhaust and curling up at the end of the exhaust pipe, finishing in the middle of the pipe. You still have a quieting effect but water can't run up the exhaust. Steve Moritz (again) had this on one of his boats. Will see if I can find a pic.
Bob

Hi Bob
Thanks for the info will work with that re engine location and the exhaust -wasnt really thinking about quieting it was more about cooling it but on this type of boat probably irrelevant.
Will try your suggestions re prop
thanks again
Will

Kevin
Email sent regarding props.
Greg