ford xld / endura-d borg warner engine rotation

[dew]

This subject is becoming a pain for me. The engine rotates ccw as I understand looking from the flywheel end and therefore must rotate cw from the cam belt end. Borg warner boxes have an output the same as input.

I have done alot of reading on which gearbox to get for this engine rotation and if most engines rotate the same as the ford xld then the standard 71c/72c box should be the right one.

So, the engine turns right, the gearbox input will turn right and the prop will rotate right and therefore the prop will need to be a rh prop. This all seems wrong to me, somehow but this is what I was told by the guy I attempted to buy a gearbox from and it all makes sense from a logic point of view but as rh would be non standard rotation and the ford engine rotates in the standard rotation.

Can anyone solve this once and for all?

 

[Jcorstorphine]

Easy to get this wrong.

The Ford XLD rotates clockwise when viewed from the front of the engine and therfore anticlockwise when viewed from the flywheel. If there was no gearbox and you had direct drive from the engine to the prop, the prop would turn clockwise when viwed from the engine and anticlockwise when viewed from the stern of the boat. This would require a LEFT HAND PROP.

Now most gearboxes have a reduction gear built in which reverses the direction of the prop roatation. These engines will require a RIGHT HAND PROP.

The exceptions being early Watermoata as they have a chain drive reduction box so the prop runs the same direction as the engine. The other one that I know of is Volvo which also has the same output direct as the engine. For these engines you need a LEFT HAND PROP.

In your case you have a direct drive so I assume that the BW does not reverse the direction of the output and you would need a LEFT HAND PROP.

"Simples" (I Think!!!!!)

 

[dew]

because a left hand prop pushes when turning right as viewed from the engine?

 

[Latestarter1]

Yes.

You are quite correct in your understanding, your engine is as you correctly refer CCW (counter closkwise rotation).

SAE J824 is convention which actually defines engine rotation, CCW and CW WHEN VIEWED FROM THE REAR OF THE ENGINE. Once people start referring to rotation viewed from the front life becomes real confusing. Engine rotation is always defined from the rear

BW71C is not a good choice for your boat as already pointed out, XLD 4,000 rpm motor. You will require a wee 91/2 X 91/2 in LH prop, running at 2,000 rpm will give 7 around knots.

Your B W is only capable of transmitting the engine's full power through one of the two sets of internal clutches, in ahead, power is transmitted through the forward or main clutch and output though main clutch is same direction as engine rotation CCW.

Remember in the case of a typical co-axial transmission, the LH prop is slightly more efficient as you are transmitting the power from the engine to the propeller through one less "pair" of meshing gears

 

[dew]

Thanks for your reply.

I know you say the engine and gearbox aren't perfectly matched especially as the bw has a max rpm of 3500 and I understand I wont get full revs, but I can only have a max prop of around 13 anyway and at the minute I have a 12 / 8. It is a compromise I can live with and the only sensible box would be a 1.5:1 prm but they seem too rare and I would need to change props. I already cancelled the purchase of the bw for now why I get the engine sorted out.

My main worry if any at all is the bottom end speed being too high.

I have had alot of really good advice and I am very grateful but I live a shoestring lifestyle on a shoestring budget and just have to make the best of what I have.

 

[Jcorstorphine]

One point I would make is that the 1.8 xld has two drive belts, one for the fuel pump and the other for the camshaft. If the camshaft belt goes, you will get damage to the cylinder head so you should look at changing the belts, it not a big job and you can get the timing tools off ebay or make them with details given in the haynes book

http://www.ebay.co.uk/itm/FORD-DIES...es_Manuals_Litterature_ET&hash=item5d3ee1f28d

 

[dew]

Yeah, thankyou. I have that covered. The engine has been run only once when I first got it about three years by me just to see if it smokes etc and it ran perfectly. The only thing about the running of the engine that is a minor concern is the advance solenoid setting and if the engine will need governing. It's a bosh pump which is good but has a stop solenoid and two other solenoids on the side at the bottom. The cam belt is the only part i dont really like about the engine, actually.