1994 mercuiser 5.0 LX belt issue

[young fella]

Hey guys, I love the forum and figured I would join in.
I recently moved down to Ft. Walton Beach, Fl with the Air Force and (with the wife's blessing) acquired my first boat! a 21' wellcraft. I do most of my own repairs on my vehicles but I'm new to boating.

The issue I'm having is with either the alternator or having the correct belt tension. After starting, the belt sqeals pretty bad and I have low voltage (12). Then after a few mins the squeaking stops and voltage pops up to 14ish. The guy I bought the boat from said the alternator was new.

The alternator appears to be spinning the entire time.

Do you guys know how much deflection the belt should have when tensioned correctly? Mine is around 1 and 3/4 inches.

Thanks in advanced!

 

[alldodge]

Might just need a new belt, or someone installed the incorrect width belt.
If the belt is below the top of the pulleys, then it has wear. It is normal that the ALT stay at 12V until the rpm comes above about 1200 rpm, but will go up over a time period

 

[EchoEv1]

Hey heres a formula. Its from the website below ehich has tons of info.

Belt Length = 2C + 1.57 x (D1 + D2) + 1”

Where
C = The distance between the motor and fan shafts
D1 = The diameter of the small pulley
D2 = The diameter of the large pulley

link:
http://www.contractingbusiness.com/service/sizing-replacement-fan-belt

 

[EchoEv1]

Also here is a general rule of thumb

 

[wellcraft-classic210]

Wondering if that a v style belt -- and if so re your pulleys rusty ??

Why do I ask?

I had an 88 Wellcraft 5.0 that wore belts down quickly from rust -- It left black rubber on the engine cover and i had to arry spare belts -- UtilI was able to resolve it for good by using a POR15 starter kit and following the directions with an added wet sanding in between cots for a smooth surface.

 

[young fella]

Thanks for the info guys. I'm gonna try throwing a new belt on with the tension info that was shared.

And yes, some of the pulleys are a little rusty. If it's still wearing after I put the new belt on, I'll try the POR15.

 

[Bondo]

And yes, some of the pulleys are a little rusty.

Ayuh,..... Welcome Aboard,..... Sand 'em to get rid of the rust, 'n shoot 'em with rattlecan Rustoleum,.....

Sooner the better,.....
​​​​​​​It drys slow, but is good motor, 'n pulley paint,....