XLD 'fan' belt

[nortonmotors]

I have a sailboat with a Ford XLD 1.6 engine (ex 1982-ish Fiesta) using the original size vee belt to drive engine coolant pump and alternator.
Having fitted a larger alternator and separate charge regulator, I now find that the belt is wearing very quickly and needs replacing several times in a season.
Before I open my wallet to Lancing Marine, has anyone done a conversion to a larger belt size, or even a poly-vee belt using off-the-shelf bits?
Sea water feed to the exhaust heat exchanger is by a direct-drive Johnson pump mounted on the face of the crank pulley.

 

[Billjratt]

Just how big is the alternator???? It will only run at full pelt for a short time -until the battery voltage rises to normal level, then it becomes about the same load as the original alternator (I'm ignoring the separate regulator - is it a Sterling?) Do you hear belt squeal on startup? Have you fitted an absurdly small alternator pulley?
My immediate thought is alignment of the pulleys, could that have altered when you changed the alternator? Can you see from the black dust pattern which pulley is eating the belt?

 

[nortonmotors]

The alternator is Lucas, max 70 amp, and the regulator is a Balmar Maxcharge MC-612N. There's no squeal when the belt is tensioned correctly, but it becomes slack after a few hours and squeals, particularly when the domestic battery is being charged. Pulleys are standard for the 1.6 XLD. There's too much dust about now to be sure, but I guess it must be the alternator, the smallest of the three.
I'm told that later 1.8 engines used a poly-vee pulley but no-one can tell me if that crank pulley will fit the 1.6 engine.

 

[Hadenough]

I had the same problem with the old boat, got one of these -

http://www.asap-supplies.com/marine/link-belts-v-belts-vee-belts-polyvee-belts

It's been on for four years now with just an annual adjustment.

 

[Jcorstorphine]

I have a Ford 1600 Diesel in my boat and it chewed belts at a great rate. The one I use is an 838 (I think) however my problem was that the pulley wheels were very badly rusted. Polished them up and it has been fine for the last two years.

Having rebuilt my 1600 down to the last nut and bolt I am pretty sure that the main drive pully on the 1800 engine will not fit the 1600. The 1600 engine has a gear driven fuel pump from the crankshaft and a cambelt from the fuel pump to the camshaft. The 1800 has one toothed drive pully at the back of the alternator pully which which drives that injection pump and a second crankshaft toothed puly which drives the oil pump and the camshaft. So basically the layout is very different.

 

[nortonmotors]

My neighbour came round with the Bodger's Guide for the two engines (aka Haynes Manual) and I see the pulley/crankshaft arrangement is completely different on the 1.8.
I'll have a closer look at the pulley grooves and see if that might be the problem. Getting the crank pulley off with the engine in the boat might be a challenge!
Thanks to all for the suggestions.

 

[Jcorstorphine]

My neighbour came round with the Bodger's Guide for the two engines (aka Haynes Manual) and I see the pulley/crankshaft arrangement is completely different on the 1.8.
I'll have a closer look at the pulley grooves and see if that might be the problem. Getting the crank pulley off with the engine in the boat might be a challenge!
Thanks to all for the suggestions.

Removing the crankshaft pulley boat is not a good idea. The pulley has the land area for the front crankshaft seal and removing the pulley will disturb the seal. Other issue is the bolt which holds the pulley to the crankshaft is about 20 mm diameter by 100 mm long and is of the "torque to yield" type and is a "one use" bolt and should be renewed, and they are non stock. I had to resort to estimating the torque and used 300 nM. If this bolt is not tight enough, the loss of clamping force on the main gear will cause the entire engine timing to be lost, result, broken valves, damaged head, possible broken camshaft.