Alternator Belt

[mark99]

The belt driving the alternator has a code written on it as follows:

 

H47NV273 274 275 followed by:

 

A44.75 13X1145Li 1175 LP

 

I'm looking for a replacment - any idea which one as the codes above yield no joy on google.

 

 

[Scholar Gypsy]

The key numbers here are 1145 (Length) x 13 (width) in millimetres.

 

A bit of googling on 13x1145 suggests this or this.

 

There appear to be several ways of measuring length - internal (Li) external (La) or something in-between (Lp). I think this article (or this one) explains, but it is not quite clear if this relates to automotive/marine engine parts.

 

So in addition to working out which length measurement you need (1145 Li = internal), you also need the profile/shape. Mine is a SPZ 10 x 1000 La for example, which is easy to source.

 

I am guessing now, but yours might be a SPZ, although the websites say the difference between Li and Lp is 37mm while yours appears to be 30 (1175-1145)!

 

Hope this helps!

[Scholar Gypsy]

PS I assume yours is a v-belt not a flat one? Does it also drive the water pump?

[mark99]

PS I assume yours is a v-belt not a flat one? Does it also drive the water pump?

 

 

Yes v belt and yes drives water pump too.There are two belts actually in parallel - both with same code number.

 

Thanks.

 

 

 

You can see both belts here below. (Dark strip on rhs).

 

 

Edited September 15, 2014 by mark99

[LEO]

Mark,

 

Is your water pump belt driven?, I thought 2LW's had a water pump drive from the engine.

 

M.

[mark99]

Mark,

 

Is your water pump belt driven?, I thought 2LW's had a water pump drive from the engine.

 

M.

 

Actually Mike you are correct. I was going by increasingly dodgy memory, I cannot take off the belt cover (to see the drive pulley and anything else) unless I strip down the cooling/heating circuit plumbing. By shining a torch in that area I thought I saw another pulley but that was months ago now.

 

Has yours got a double groove drive pulley for the alt?.

Edited September 15, 2014 by mark99

[David Mack]

 

A44.75 13X1145Li 1175 LP

The key numbers here are 1145 (Length) x 13 (width) in millimetres.

 

A bit of googling on 13x1145 suggests this or this.

 

There appear to be several ways of measuring length - internal (Li) external (La) or something in-between (Lp). I think this article (or this one) explains, but it is not quite clear if this relates to automotive/marine engine parts.

 

So in addition to working out which length measurement you need (1145 Li = internal), you also need the profile/shape. Mine is a SPZ 10 x 1000 La for example, which is easy to source.

 

The A indicates an A section v belt which is 0.5 inch / 13mm wide.

 

The belt you want has an internal length (Li) of 1145 mm and a pitch length (Lp) of 1175mm. The Kramp belt in Simon's second link looks a bit short (Li = 1145-63 = 1082mm). I would suggest this which has an internal length of 1145mm.

 

I think the 44.75 in the reference is the nominal length in inches, but since 44.75 inches = 1137mm there seems to be some rounding going on between the imperial and metric dimensions.

[Tonka]

As there is 2 do they have to be a matched pair. On a Petter Pd2 I had to fit a matched pair

[LEO]

 

Actually Mike you are correct. I was going by increasingly dodgy memory, I cannot take off the belt cover (to see the drive pulley and anything else) unless I strip down the cooling/heating circuit plumbing. By shining a torch in that area I thought I saw another pulley but that was months ago now.

 

Has yours got a double groove drive pulley for the alt?.

 

Mark,

 

No, my 2LW has one belt which drives a 90amp alternator. The pulley on the crankshaft is probably about 12" diameter.

 

I have a spare belt which came with the boat, will try to dig it out and get details.

 

Of course the best thing about this arrangement is that if the belt breaks, water still circulates and no overheating occurs.

 

Now about that pole..............

 

ATB

 

Mike.