The Fordson Tractor Pages Forum

I was playing with the major today and looking into what sounds like a squeaky water pump, when I noticed the dynamo pulley doesnt line up with the other two pulley's very well, so the fan belt runs at an angle. Is this normal ? or has something been changed that shouldn't have been?

Thanks

To me this is not normal. They should be in one line. Give us a picture.

Not sure if the pic shows it very well, but you can see the belt doesn't sit in the centre of the dynamo pulley.

http://i689.photobucket.com/albums/vv25 ... G_0386.jpg

brinky wrote:Not sure if the pic shows it very well, but you can see the belt doesn't sit in the centre of the dynamo pulley.

http://i689.photobucket.com/albums/vv25 ... G_0386.jpg

it looks like the bracket at the top is bent slightly

Can't really tell from the picture but you look to have a wide fan belt dynamo and water pump pulley and possibly a narrow fan belt crankshaft pulley. The belt is running way down the dynamo pulley and that is not normal, the belt usually runs level with the pulley sides at the top.

My dynamo is not supported from above. Looks like it's also a bit pressed to the front by that support.

Maybe the next pictures will help.

The pulley does indeed appear to be too wide AND the unit needs to be shimmed forward to properly line up with the crankshaft and water pump pulleys.

If I may make an observation: It isn't so much that the genny needs shimming forward as re-aligned parallel to the crankcase - ie the front lower mounting hole is closer to the block [or the rear one is further away from it].
I had this same problem when converting to an alternator.
As to fanbelts; my opinion is that it is better to use the belt best fitting the driving pulley, the crankshaft one - 11mm, rather than the size required by the driven ones [13mm]. Using a wider belt in narrower pulleys can split a pressed steel pulley if overly tensioned.
Pavel

But using a narrow belt on a wide pulley can mean the sides do not grip the belt and it just spins round on the hub Found out the hard way on my potato harvester last year!

Ok, out of interest what size pulleys should be on the major??
I guess it doesn't matter as long as they are the same and and have the correct belt, are are obviously in line.
Thanks for all the responses...

I guess it's six of one and half a dozen of the other as far as odd pulley sizes are concerned. And I take your point, Brian. 'Course, with a cast iron pulley splitting is not a problem. But I do remember scratching my head many years ago as to why a substantial slip clutch kept operating after fitting an overwide belt.
Pavel

It is best to go to an electrical rebuild shop and have the narrow pulley on the alternator changed to a wide one that matches the tractor. I've done this a number of times though the years. Dandy Dave!