The Ford Barn

hombres ruin · 03-26-2020, 08:29 PM

Hi guys . Could be a stupid question but here goes . How tight should the fan belt be? I have a 41 flathead and I hear differing options on how tight the belt should be. Too tight and the generator could get damaged . My gen has been re built and new water pumps and a new belt was put on about 6 months ago. At higher RPMs the gen makes a noise like a rusty machine type thing, at idle not a lot of noise but some . I have the correct belt. I took it to the re builder to check it out and he said that there is wear on the narrow part of the pulley ,he put it on his machine and said it was fine. He will pull it apart to make sure it’s all good .. but have I had this belt on too tight , how loose should it be? Thanks guys

JSeery · 03-26-2020, 08:39 PM

The belts only need to be tight enough to prevent slippage.

Tinker · 03-26-2020, 08:41 PM

Think 1/4" movement with a finger is considered about right. But as JSeery said.

aussie merc · 03-26-2020, 11:21 PM

ive always been told 1" on the left side between the gen and water pump [history lesson i though it was to loose tightend it up and then promptly overloaded the water pumps and had to replace them ] if the belts noisy try rubbing the V with some hard bar soap works a treat

Tinker · 03-26-2020, 11:32 PM

https://www.earlyfordv8.org/forum/pr...18&Topic=10581

Post from len47merc about halfway down. 1/2".

Same as Old Henry - just with a screwdriver for me.

Regarding the belt deflection specification/tightness, I too always adjust mine as TomO states and have never had a problem or prematurely worn belt; however, Fig. 11 on Page P-4 of the 1942-1948 SHOP MANUAL shows 1/2" FREE MOVEMENT as the tightness setting. I typically tighten just to the point there is no excess belt movement at rpm which equates to approximately 1" deflection. You be the judge of what works best for you.

Steve

Don't think it would be much different for a 41. But someone will let me know I'm sure.

hombres ruin · 03-27-2020, 08:24 AM

Sponsored Links (Register now to hide all advertisements)

Thanks guys good info for sure , I will make the advises adjustments once the gen is back. Is there anything I could apply to the belt to make it less noisy?

KGS · 03-27-2020, 08:50 AM

Quote:

Originally Posted by hombres ruin

Thanks guys good info for sure , I will make the advises adjustments once the gen is back. Is there anything I could apply to the belt to make it less noisy?

A new belt adjusted properly should run quiet and shouldn't need anything added to it.
Ken

tubman · 03-27-2020, 10:19 AM

My old man must not have been much good at adjusting belts, because he always had a tube of "Belt Dressing" available. He used it on his cars, the power saw, joiner, and drill press in his shop, as well as the riding lawnmower.

I believe that they made it back then because nobody replaced belts until they broke. Got a little slippage? Hit it with the belt dressing.

It must be good for something. a lot of companies (e.g. Grainger) still sell it.

B-O-B · 03-27-2020, 01:22 PM

I have always adjusted mine to 1/2" deflection & used soap if noisy.

RKS.PA · 03-28-2020, 08:43 AM

Quote:

Originally Posted by tubman

My old man must not have been much good at adjusting belts, because he always had a tube of "Belt Dressing" available. He used it on his cars, the power saw, joiner, and drill press in his shop, as well as the riding lawnmower.

I believe that they made it back then because nobody replaced belts until they broke. Got a little slippage? Hit it with the belt dressing.

It must be good for something. a lot of companies (e.g. Grainger) still sell it.

Tub, when I was about 12 years old, my job was mowing our lawn. The belt on the mower looked like it needed some attention. I put motor oil on it....lesson for that day.....motor oil is not rubber belt dressing!!

03-26-2020, 08:29 PM	#1
hombres ruin Senior Member Join Date: May 2010 Location: san diego Posts: 518	How tight is tight and how loose is loose Hi guys . Could be a stupid question but here goes . How tight should the fan belt be? I have a 41 flathead and I hear differing options on how tight the belt should be. Too tight and the generator could get damaged . My gen has been re built and new water pumps and a new belt was put on about 6 months ago. At higher RPMs the gen makes a noise like a rusty machine type thing, at idle not a lot of noise but some . I have the correct belt. I took it to the re builder to check it out and he said that there is wear on the narrow part of the pulley ,he put it on his machine and said it was fine. He will pull it apart to make sure it’s all good .. but have I had this belt on too tight , how loose should it be? Thanks guys __________________ "I have built my organisation on fear"..Al Capone.

03-26-2020, 08:39 PM	#2
JSeery Member Emeritus Join Date: Nov 2012 Location: Wichita KS Posts: 16,132	Re: How tight is tight and how loose is loose The belts only need to be tight enough to prevent slippage.

03-26-2020, 08:41 PM	#3
Tinker Senior Member Join Date: May 2010 Location: MN Posts: 7,053	Re: How tight is tight and how loose is loose Think 1/4" movement with a finger is considered about right. But as JSeery said.

03-26-2020, 11:21 PM	#4
aussie merc Senior Member Join Date: Sep 2016 Location: sydney australia Posts: 1,030	Re: How tight is tight and how loose is loose ive always been told 1" on the left side between the gen and water pump [history lesson i though it was to loose tightend it up and then promptly overloaded the water pumps and had to replace them ] if the belts noisy try rubbing the V with some hard bar soap works a treat

03-26-2020, 11:32 PM	#5
Tinker Senior Member Join Date: May 2010 Location: MN Posts: 7,053	Re: How tight is tight and how loose is loose https://www.earlyfordv8.org/forum/pr...18&Topic=10581 Post from len47merc about halfway down. 1/2". Same as Old Henry - just with a screwdriver for me. Regarding the belt deflection specification/tightness, I too always adjust mine as TomO states and have never had a problem or prematurely worn belt; however, Fig. 11 on Page P-4 of the 1942-1948 SHOP MANUAL shows 1/2" FREE MOVEMENT as the tightness setting. I typically tighten just to the point there is no excess belt movement at rpm which equates to approximately 1" deflection. You be the judge of what works best for you. Steve Don't think it would be much different for a 41. But someone will let me know I'm sure. Last edited by Tinker; 03-26-2020 at 11:51 PM.

03-27-2020, 08:24 AM	#6
hombres ruin Senior Member Join Date: May 2010 Location: san diego Posts: 518	Re: How tight is tight and how loose is loose Sponsored Links (Register now to hide all advertisements) Thanks guys good info for sure , I will make the advises adjustments once the gen is back. Is there anything I could apply to the belt to make it less noisy? __________________ "I have built my organisation on fear"..Al Capone.

03-27-2020, 10:19 AM	#8
tubman Senior Member Join Date: Dec 2013 Location: Minnesota, Florida Keys Posts: 10,303	Re: How tight is tight and how loose is loose My old man must not have been much good at adjusting belts, because he always had a tube of "Belt Dressing" available. He used it on his cars, the power saw, joiner, and drill press in his shop, as well as the riding lawnmower. I believe that they made it back then because nobody replaced belts until they broke. Got a little slippage? Hit it with the belt dressing. It must be good for something. a lot of companies (e.g. Grainger) still sell it.

03-27-2020, 01:22 PM	#9
B-O-B Senior Member Join Date: May 2010 Location: Ft Mohave,Az Posts: 1,987	Re: How tight is tight and how loose is loose I have always adjusted mine to 1/2" deflection & used soap if noisy.