Right or left handed propellor identification...

[boatymum]

Hello and nice to meet you.

 

I have a silly question, but despite looking up loads of propellor pictures on the web, I am still totally confused about left and right propellors.

 

We have just had a boat built and fitted with a Petter AV2 engine. The man who sold the engine to us told us to get a right hand propellor. This information was passed to the boatbuilders and a lovely brass propellor was put on. The boat was finished, delivered and put in the water and then inspected by another engine man who knows Petters. He said the propellor was the wrong way round for the engine and that it goes backwards when it should be going forwards. I then contacted the boat builders who said they were sorry and would order another. They contacted the propellor suppliers and were told that a right hand one had been supplied. So I was to contact the propellor suppliers tomorrow and talk to them.

 

I shall attempt to post some pics and maybe one of you will be able to see, because it has to be one or the other..... if it wasn't going to be so expensive, it would be Monty Python sort of funny.

 

[bizzard]

Hello and nice to meet you.

 

I have a silly question, but despite looking up loads of propellor pictures on the web, I am still totally confused about left and right propellors.

 

We have just had a boat built and fitted with a Petter AV2 engine. The man who sold the engine to us told us to get a right hand propellor. This information was passed to the boatbuilders and a lovely brass propellor was put on. The boat was finished, delivered and put in the water and then inspected by another engine man who knows Petters. He said the propellor was the wrong way round for the engine and that it goes backwards when it should be going forwards. I then contacted the boat builders who said they were sorry and would order another. They contacted the propellor suppliers and were told that a right hand one had been supplied. So I was to contact the propellor suppliers tomorrow and talk to them.

 

I shall attempt to post some pics and maybe one of you will be able to see, because it has to be one or the other..... if it wasn't going to be so expensive, it would be Monty Python sort of funny.

 

The propeller in this photo is a R/Handed one.

[boatymum]

Thank you very much indeed. Good job I don't yell at people.

[bizzard]

Thank you very much indeed. Good job I don't yell at people.

If you start the engine and put it into forward gear and stand behind the engine right at the stern looking forward at it the propshaft should be revolving in a clock-wise direction for a R/H prop. Then obviously if it revolves in the anti-clockwise direction when in forward gear it would need a L/H prop.

Edited January 9, 2013 by bizzard

[boatymum]

I tried to say thank you last night, but the internet bombed out on me. We shall try that later.

[RLWP]

Could you post some pictures of the engine and gearbox as well please? There will be enough knowledge on here somewhere to sort this puzzle out

 

Richard

[boatymum]

 

Thank you. Your help is really appreciated. I'm meant to be chatting to the prop guy today and i still don't know what I'm talking about.

 

P.S. The boatbuilders have spoken to the prop people and they confirmed they only provided R/H props unless told otherwise, so no mistakes by boatbuilders. Maybe it is a leftie engine.

Edited January 9, 2013 by boatymum

[Keeping Up]

When a friend of ours had a boat created by adding a new back-end to an old Bantock front half, the yard fitted it with a Lister FR3 and matching Lister gearbox, and a very nice job they did too. We all jumped aboard for a trial run - and set off backwards down the canal. They had not realised which direction the prop would rotate.

[Timleech]

That looks very much like a 3-wheel reduction gear on there. I've never seen one before on that type (Newage) of box. They reverse the 'normal' prop rotation by introducing an extra gear into the train. Usually done for twin-engine installations, so that the props on the two engines rotate in opposite directions. I don't know for sure whether the Petter AV has 'normal' rotation, but the 3-wheel box would explain your little difficulty.

 

Tim

[Iain_S]

I don't think I've even seen an AV2, but from

and

it looks like the AV2 rotates clockwise from the flywheel end and anti-clockwise from the other (gearbox) end. However, there is a reduction unit fitted on the back of the gearbox, which, if it's similar/identical to the Lister unit, will reverse the direction of rotation, so right handed prop. (I think!)

 

Bottom line, does it go forwards with the gearbox in forward gear?

(or, if it's out of the water, does the prop rotate clockwise looking from behind when engine turned over in forward gear?)

 

Iain

[boatymum]

The chap who sold the petter engine and apparently reconditioned it, told us to get the righty prop, so it is him I need to ask.

 

My brother is going down to have another look at the rotation for himself. He knows engines so he cannot be wrong. What a crazy problem to have.....

 

How much of an issue is it to drive a boat in reverse gear. Would it blow something?

 

It is very in the water and the two seasoned marina chaps are going to have a look but I am meant to be getting a new correct propellor for them.

 

My best bet would be to order the opposite one anyway and return the one we don't use. Then in my ignorance, I am covered.

Edited January 9, 2013 by boatymum

[Chris Pink]

 

 

My best bet would be to order the opposite one anyway and return the one we don't use. Then in my ignorance, I am covered.

 

You do need to establish which you need first.

 

The advice here is to spin the engine, either with a hand start if fitted or briefly on the starter motor and observe which way the fitted propellor spins.

 

To just swap the propellor is not a good solution at this point, as Tim says, whether or not the Petter is a left handed engine you might have a reduction gear that makes it spin the opposite way which would accord with the engine rebuilder who should, in all reality, be the person who knows.

 

Does it have a hand start? if so it will be easy to find out.

[Keeping Up]

How much of an issue is it to drive a boat in reverse gear. Would it blow something?

 

 

I don't know this particualr unit but most boxes of this era (and some today) will only tolerate about 10-15 minutes in reverse before they start to protest.

[boatymum]

Okey dokey. Brother has been dispatched to find out exactly which way it rotates. He already knows it is wrong but is checking again with all your info texted to him. I shall just find out how fast a leftie prop can be obtained.

 

You guys are so fabulous. I was tearing my hair out before finding this forum. Nothing was making any sense.

 

Also I will phone the engine chappie and double check.

 

UPDATE

 

Brother says when behind boat, prop goes anticlockwise, engine clockwise....

Edited January 9, 2013 by boatymum

[RLWP]

That looks very much like a 3-wheel reduction gear on there. I've never seen one before on that type (Newage) of box. They reverse the 'normal' prop rotation by introducing an extra gear into the train. Usually done for twin-engine installations, so that the props on the two engines rotate in opposite directions. I don't know for sure whether the Petter AV has 'normal' rotation, but the 3-wheel box would explain your little difficulty.

 

Tim

 

I'm linking directly to the image as I find the thumbnails frustrating

 

 

That's the extra lump on the reduction box Tim?

 

Richard

[Timleech]

I'm linking directly to the image as I find the thumbnails frustrating

 

 

That's the extra lump on the reduction box Tim?

 

Richard

 

The power bulge

 

Tim

[boatymum]

UPDATE

 

Brother says there are no markings of forward or reverse on engine and he is assuming that reverse is pulling the switch to the rear of the boat and forwards is forwards and is now beginning to doubt his own integrity.....

[RLWP]

The extra wheel in the reduction housing is in the bit circled. As Tim says, pretty unusual

 

 

Richard

 

MORE: Yes, lever forward for forwards, lever backwards for reverse

Edited January 9, 2013 by RLWP

[boatymum]

photo uploader

 

pic upload

 

free photo hosting

Edited January 9, 2013 by boatymum

[boatymum]

The nice thing is that apparently the engine sounds wonderful. Unfortunately this is going to be hugely expensive to put right. Apparently the boat has to be lifted out of the water again which involves full crane costs plus labour. That blows the entire budget for any windows. We shall have to paint them on!!!

[Chris Pink]

The nice thing is that apparently the engine sounds wonderful. Unfortunately this is going to be hugely expensive to put right. Apparently the boat has to be lifted out of the water again which involves full crane costs plus labour. That blows the entire budget for any windows. We shall have to paint them on!!!

 

I'm a bit confused; does this mean you have definitely established that if you move the gear lever forwards the boat goes backward?

 

It isn't clear from your previous posts./

[Timleech]

The nice thing is that apparently the engine sounds wonderful. Unfortunately this is going to be hugely expensive to put right. Apparently the boat has to be lifted out of the water again which involves full crane costs plus labour. That blows the entire budget for any windows. We shall have to paint them on!!!

 

Send the bill to whoever told you fit a right-handed prop!

 

Tim

[Tam & Di]

Send the bill to whoever told you fit a right-handed prop!

 

Tim

 

Absolutely! Presumably you don't actually have anything from the seller in writing to that effect though, which might make things difficult as I can't see him agreeing without an argument.

[ChimneyChain]

Give jim Perkins a ring at petter engines he'll know straight away 0794 6470023.

 

Darren

[boatymum]

I'm a bit confused; does this mean you have definitely established that if you move the gear lever forwards the boat goes backward?

 

It isn't clear from your previous posts./

 

A fine question... I will ask brother. I wasn't on the boat when he and the engine chap started it. It will be even more Monty Python if it works perfectly forwards after all this panic. I cannot imagine two engine minded boys would be wrong when puzzling it over together, but stranger things have happened at sea....