would it be alright to weld a v-belt pulley to my alternator pulley? i need to add a pulley so i can run my plow pump, but i dont have the extra cash to buy one from fisher $110... so i thought i could just weld one on as long as its centered and it has plenty of clearance. what you guys thought on this?

thanks Derek

 

You are taking a chance, but if you can center it OK, why not. Make sure the ground wire is on the pulley and not anywhere in the alternator. Be careful about heat transfer thru the shaft.
To be safe and if you can easily remove the alternator diodes, then I would remove them first.

 

if i did weld it i would remove the pulley. and have a professional do the welding/centering.

 

Then as long as they are both the same material, it should be OK. There is a small possibility of premature bearing failure with the additional load.

Years ago I needed to do something similar and went to the junk yard and found a double pulley off a Caddy that I adapted. Couldn't you do something similar?

 

Check with an alternator rebuild shop they probably would have a new or used one that would work for you.. A double alternator pulley is not that uncommon.

 

It can be done; we did a similar thing for running on-board air on a friend’s jeep...

I would defiantly remove the pulley from the truck, not only to avoid doing damage to the alternator but it is much easier to do the centering and welding on the bench…if either pulley is cast it will be a huge pain in the but…I’d suggest finding another pulley or buying one…

Dissimilar metals are not a problem as long as you can determine what filler or rod should be used.

Not to insult you in any way, but I would suggest having a shop center and weld the pulley unless you’re rather proficient with measuring equipment and as a welder…if you end up messing the bearing up or something else happens it would cost you wayyy more in the end…

I am a machinist and welder by trade, here is how I did it….
I held the two sandblasted pulleys on a table with a long bolt welded perpendicular to the table. I turned a step bushing on the lathe that was a tight fit to the ID of the pulleys with a hole to fit the bolt thru it. Tightened that down and double checked the OD of the pulleys with depth mics. I TIG welded the two together, running small beads on opposite sides and making sure to let them cool between passes. In our case we were able to use E9018 filler wire for welding the two together…

I’ve also made the whole thing, just a new double or triple pulley out of a solid piece of stock, aluminum works great!! If your know anyone with a lathe and some machine tools you could have a new one made…the hardest part of that is finding the tooling to broach a keyway if it needs one…

Hope that helps!

 

I cant imagine the pulley being an alloy steel so the weld should be ok.
you will be loading your bearings more.
you need to get the two pulleys centered. I would say within .030 or less.

 

If they are out of balance you can ruin a bearing too.....

 

After welding I would check run out if it was me.