Series 102 engine with a forty five blade prop
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Series 102 engine with a forty five blade prop
Having re built what is now a very decent 102 series engine from a crate of parts donated to me I find that the only prop that I have is a 9" five blade one marked 'Forty Only " can I use that type?
Correction, the prop is marked 100 only.
Correction, the prop is marked 100 only.
Last edited by african imp on Sun Jan 06, 2019 7:41 am, edited 1 time in total.
Re: Series 102 engine with a forty five blade prop
If it will fit on the gearbox, then yes... but you will need to re pitch it or your engine will over rev and you won't go anywhere.
To re pitch the prop you need to anneal it first (this will help it bend) The aluminium needs to be heated up to the point where you can draw on it with a matchstick. You are not trying to light the match, but leave a black mark from it like drawing on paper with a pencil. The other thing you need is some way to measure the blades so they all end up the same. How much to bend them is a guess, try it and see. Take a block of wood and a hammer with you it your boat and you can fix it on the fly.
To re pitch the prop you need to anneal it first (this will help it bend) The aluminium needs to be heated up to the point where you can draw on it with a matchstick. You are not trying to light the match, but leave a black mark from it like drawing on paper with a pencil. The other thing you need is some way to measure the blades so they all end up the same. How much to bend them is a guess, try it and see. Take a block of wood and a hammer with you it your boat and you can fix it on the fly.
"THE KING OF BLING"!
Is it better to over think, than not think at all?
Is it better to over think, than not think at all?
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Re: Series 102 engine with a forty five blade prop
Thanks,
What prop was this motor fitted with, I have read that a two blade one was used post WW2 but that was changed later, can anyone post a picture f a prop that I could use with out bending the blades of the one that I have?
What prop was this motor fitted with, I have read that a two blade one was used post WW2 but that was changed later, can anyone post a picture f a prop that I could use with out bending the blades of the one that I have?
Re: Series 102 engine with a forty five blade prop
Others may correct me, but for me, a blade marked 'Forty' implies 'Forty Plus' motors, and I don't recall any Forty Plus motor being fitted with a five blade prop.
The five blade props I am aware of - and I recall there were certainly three different sizes - were fitted to the 'Century' groups of motor, and were usually marked 'Century', '100' etc.
The 102 was variously fitted with a four blade 'Hydrofan ' type prop at some point, duly marked '102', the other 102 props being the swept-back two blade, the so-called 'bowtie' prop, and a broad-bladed three blade semi-weedless type.
The five blade props I am aware of - and I recall there were certainly three different sizes - were fitted to the 'Century' groups of motor, and were usually marked 'Century', '100' etc.
The 102 was variously fitted with a four blade 'Hydrofan ' type prop at some point, duly marked '102', the other 102 props being the swept-back two blade, the so-called 'bowtie' prop, and a broad-bladed three blade semi-weedless type.
Re: Series 102 engine with a forty five blade prop
Yep. If straight out exhaust.
If the pointing down exhaust (subejector)
Wow. I just accessed this forum by phone and took photo and it came staight on. So much easier. Except they are sideways. Note take photo sideways.-
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Re: Series 102 engine with a forty five blade prop
Guys, thanks on your replies and advice, I have just checked the five bladed prop and it is marked '100 only' not forty, my mistake.
The question remains will this five bladed prop be too small for the 102 motor?
Serial number TC 82813 circa 1962/63?
I have built this motor up from a steel trunk load of odds and sods that were gifted to me when an outboard motor shop changed hands, the 102 motor as seen in the picture did not exist, the parts did but it is a very much mix and match type assembly.
It runs well now and has a new owner, I have a second 102 option, a part seized power head and a selection of power legs, I will require another prop should it get re assembled?
The question remains will this five bladed prop be too small for the 102 motor?
Serial number TC 82813 circa 1962/63?
I have built this motor up from a steel trunk load of odds and sods that were gifted to me when an outboard motor shop changed hands, the 102 motor as seen in the picture did not exist, the parts did but it is a very much mix and match type assembly.
It runs well now and has a new owner, I have a second 102 option, a part seized power head and a selection of power legs, I will require another prop should it get re assembled?
Re: Series 102 engine with a forty five blade prop
Just pop it on a boat and try it. What ratio box are you using? They differ. You are asking us how long a piece of string is. What size boat are you pushing? What is the porting configeration of the barrel? What is the shape of the piston and the affect of scavenging? Which carburetor are you using and what size jets. Which magneto and the list goes on.
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Re: Series 102 engine with a forty five blade prop
Thanks for the advice!
Given that this entire motor was assembled from a spare parts offer I cannot say much about what your asking, excepting it has the Villiers coil and the carb came from John at SOS and was a body repair option on the lower thread, it is the Amal 2 jet version.
I will ask the new owner to test it out on whatever boat he has in mind.
I have just checked the gear ratio to motor turning, the motor needs to turn four times to one revolution of the propeller .
Regards
Roy
Given that this entire motor was assembled from a spare parts offer I cannot say much about what your asking, excepting it has the Villiers coil and the carb came from John at SOS and was a body repair option on the lower thread, it is the Amal 2 jet version.
I will ask the new owner to test it out on whatever boat he has in mind.
I have just checked the gear ratio to motor turning, the motor needs to turn four times to one revolution of the propeller .
Regards
Roy
Re: Series 102 engine with a forty five blade prop
So you have a 4:1 gearbox - I think this qualifies as a 'Barge pusher' (Hugz?? [good info on the props by the way]) which would be yet another prop! With that ratio, just slap the prop you have on and see how it goes.
A bit difficult to see from the photo, but it looks as though there is a large distance between the water pump housing and the prop spindle , which would also suggest the barge pusher prop, which was a big (13"dia.) four bladed cloverleaf affair.
A bit difficult to see from the photo, but it looks as though there is a large distance between the water pump housing and the prop spindle , which would also suggest the barge pusher prop, which was a big (13"dia.) four bladed cloverleaf affair.
Re: Series 102 engine with a forty five blade prop
With the 102s I'm not the best to talk to on ratio's but l was under the impression the 1946 bargepusher was 4/1. The plus was 4/1 and standard was 2.5/1.
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- Posts: 395
- Joined: Thu Jan 03, 2019 5:44 am
- Location: Hout Bay
Re: Series 102 engine with a forty five blade prop
I do have a larger prop but it fouls the gear box casing.
It measures 11.25 inches.
It measures 11.25 inches.