V pulley & emery cloth

Oct 29, 2005
2,355
Hunter Marine 326 303 Singapore
I wish to run emery cloth/sandpaper on the V pulley slot face to remove any fine pitting that is creating belt dust. Any idea what grade I should use? 2000 or more?
Thanks.
 
Sep 23, 2009
1,475
O'Day 34-At Last Rock Hall, Md
Another option, I used a cone shaped grinder on a dremel tool. I don't know the grit but I think it was a medium level.
 
Oct 29, 2005
2,355
Hunter Marine 326 303 Singapore
Thanks guys. I think a sandpaper/emery cloth would be easier. Plan is take the belt off, run the engine on idle and place emery cloth in V groove to sand sides lightly. Won't run engine too long as fresh cooking water pump is not running with belt out (safety precaution).
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
Belt dust is probably not being caused by the pulley being rough. How much alternator do you drive (amps max output)? The other culprit is not having the belt tight enough. As a general rule you can not drive over 60-70 amps with a single V belt. The auto regulated alternator does not count as it only goes to max output for a short time before going to trickle charge. You can run 80+ amps with an auto regulated alternator.
 
Oct 29, 2005
2,355
Hunter Marine 326 303 Singapore
I got an 80A alternator from eBay. My belt is so wore that adjustment reaches end of swing. Gonna get a new shorter belt.
Highest charging I've seen was 30A+.
 
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Sep 23, 2009
1,475
O'Day 34-At Last Rock Hall, Md
The subject of belt dust has come up before and someone reported good results using gates green line belts. I have not tried it yet but might be worth a try. Converting to a serpentine belt is another option. Please be careful around that rotating pulley.
 
Nov 26, 2008
1,966
Endeavour 42 Cruisin
I can reduce my belt dust to almost zero when giving the engine pulley a treatment with emory cloth. I always use the good green stripe belts and tension is very tight.

I do it by just bumping the starter to move the pulley. Sand what I can reach and bump again. I dont think I would try running the engine and sticking my hand in there!!
 

pateco

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Aug 12, 2014
2,207
Hunter 31 (1983) Pompano Beach FL
I took my pulley off, and used a fine wire wheel on my bench grinder. That got it really smooth. then i put a bolt and some washers through it, and ran it on my drill with 3M compound and a terry cloth rag. It shined up like chrome.
 
Oct 29, 2005
2,355
Hunter Marine 326 303 Singapore
Thanks for all the ideas and precautions to take. I've sand it as mentioned with belt off. As for water pump and alternator pulleys I turn it by hand. Easy enough. I can feel the V groove is alot smoother now. Cleaned up the dust after sanding and oiled the V little. All is good for now. Lets see in coming weeks if another belt bites the dust...or not.
 
Oct 29, 2005
2,355
Hunter Marine 326 303 Singapore
Good! No more dust so far. I'll keep watch on it and lightly oil it as one of preventive maintenance. :D
 
Oct 29, 2005
2,355
Hunter Marine 326 303 Singapore
Put some oil on tissue/cloth and rub in to the pulley V sides so its thin coat. Tighten belt to recommended tension. It won't slip.