V Belt Suggestions - Fan spacing, pulley sizing, belt routing

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,207
Reaction score
6,187
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
So Im working on my truck and replaced alternator with a good one and the bracket which was belt and was either eating alternators or at least the bearings Im thinking and eating belts. The belt at the auto store matched to the same gates PN was 3 inches LONGER than a new one. Holy cow.

Anyway, i have a lot of SBC parts and I can set this up in many ways without buying much. I have a 2 belt crankshaft pulley, 2 belt WP, 2 belt alternator, and 2 belt ps pump.
You must be registered for see images attach

not the best pic for showing, but its 1 belt off crank, to the wp, to alt. with one belt off crank to ps pump.
the change is im putting a 2 belt alternator on in place of current one, can change other pulleys to do better/more

If I run 2 belts to anything, Id think ps pump would be best since at low speed the demand is highest? Should route straight from crank to PS? Or perhaps alternator around a WP? PS and alt?(Would require buying special pulleys lol) I guess, without considering spacing and alignment(I can do that, I will have to for my ps pump when i change the bracket) what would be the best way to route belts?

and I have a 3 blade fan. I also have a 7 blade fan. Are the fan clutches interchangeable and if so, whats better? The 7 blade fan is from a HD cooling application, so I would assume its louder?
And how far into the shroud should a fan sit? I Can move the fan in further if necessary, But incase it sat different I could fix that
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,207
Reaction score
6,187
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
@HotRodPC 3 or 7 blade fan? someones gotta have an opinion or thought to sharreee
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,207
Reaction score
6,187
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
Some pics because why not

You must be registered for see images attach


You must be registered for see images attach


You must be registered for see images attach
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,207
Reaction score
6,187
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
Found my next fan guys!

You must be registered for see images attach
 

HotRodPC

Administrator
Staff member
Admin
Joined
Aug 29, 2010
Posts
47,014
Reaction score
9,009
Location
OKC, OK
First Name
HotRod
Truck Year
85 K20 LWB
Truck Model
Silverado
Engine Size
454 - Turbo 400 - 3.73
@HotRodPC 3 or 7 blade fan? someones gotta have an opinion or thought to sharreee
I'd toss the 3 blade fan. That 4 blade fan was used in the 60's pre fan clutch. I had one like that on my I6 65 230 cu in engine. In fact that looks like the I6 fan.
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,207
Reaction score
6,187
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
I'd toss the 3 blade fan. That 4 blade fan was used in the 60's pre fan clutch. I had one like that on my I6 65 230 cu in engine. In fact that looks like the I6 fan.
it DID fit the wp, but not sure if thats the same diameter. the pulley near it had a slightly smaller bore but same bolt pattern as wp. maybe for short wp?


I put the 7 blade on my clutch and im gonna eventually get a new clutch

@HotRodPC @bucket
done for today... just getting the ps pump lined up and then to belt routing. What do you guys thiink I should do? Based on pic, its hard to tell, I could run one belt on all 4 and then a second belt around crank, wp, and ps. the WP, crank, and PS are lined up together, the alternator is back by one belt, so the outside groove is usable.
Maybe line up alt with the rest and have 2 belts all around???
Isolate a single accessory? etc

You must be registered for see images attach
 

SquareRoot

Full Access Member
Joined
Mar 18, 2017
Posts
3,695
Reaction score
6,683
Location
Arizona
First Name
Mike
Truck Year
85
Truck Model
K20
Engine Size
350
I'd shitcan it all but hey, thats just me.
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,207
Reaction score
6,187
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
I'd shitcan it all but hey, thats just me.
Real men shitcan the LS serpentine and use all electric accesories with a chain driven generator to power everything
 

SquareRoot

Full Access Member
Joined
Mar 18, 2017
Posts
3,695
Reaction score
6,683
Location
Arizona
First Name
Mike
Truck Year
85
Truck Model
K20
Engine Size
350
Real men shitcan the LS serpentine and use all electric accesories with a chain driven generator to power everything

Who said anything about an LS?
 

bucket

Super Moderator
Staff member
Super Moderator
Joined
Aug 3, 2010
Posts
29,087
Reaction score
23,895
Location
Usually not in Ohio
First Name
Andy
Truck Year
'77, '78, '79, '84, '88
Truck Model
K5 thru K30
Engine Size
350-454
Took me a minute to figure out what is going on here. To run two belts around the PS pump, you need to remove those spacers and install a 3-groove crank pulley.

Belt 1: Crank, water pump, alternator.
Belt 2: Crank, water pump, PS pump.
Belt 3: Crank, PS pump.
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,207
Reaction score
6,187
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
@bucket but could i just do 2 belts around every accessory assuming they were lined up?
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,207
Reaction score
6,187
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
Nevermind, I just realized my plan doesnt account for no iddler to keep tension on waterpump.
I was thinking with current setup, 1 belt alternator, ps pump, crank
1 belt crank, wp, ps pump
1 belt alternator and waterpump.

Can that be done? Or does the size difference cause problems?
 

bucket

Super Moderator
Staff member
Super Moderator
Joined
Aug 3, 2010
Posts
29,087
Reaction score
23,895
Location
Usually not in Ohio
First Name
Andy
Truck Year
'77, '78, '79, '84, '88
Truck Model
K5 thru K30
Engine Size
350-454
Nevermind, I just realized my plan doesnt account for no iddler to keep tension on waterpump.
I was thinking with current setup, 1 belt alternator, ps pump, crank
1 belt crank, wp, ps pump
1 belt alternator and waterpump.

Can that be done? Or does the size difference cause problems?

You could probably do that, but I don't see how there would be any benefit.
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,207
Reaction score
6,187
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
2 belts driving each accessory? with the bulk load of ps pump not taking away from alternator as it would have its own belt to help turn when ps pump is under load.
then the ps pump would have a large surface area turning it, so would water pump
 

Latest posts

Forum statistics

Threads
42,075
Posts
908,460
Members
33,548
Latest member
garethrowsell
Top