Please note this thread has been inactive for 90 days. For the best results, please start a new thread.
Results 1 to 3 of 3
  1. #1
    Seaman Apprentice bryantjb3's Avatar
    Join Date
    Apr 2005

    Default Serpentine Belt tension?

    I just replaced the power steering pulley and serpentine belt on my '97 5.7L mercruiser. The manual says to tighten belt to 1/4" deflection at longest point. How much downward pressure should I put on the belt when measuring for the deflection?

  2. #2
    Lieutenant Junior Grade
    Join Date
    Oct 2004

    Default Re: Serpentine Belt tension?

    I don't know that there is a spec for how much pressure to put on it??? I would say to use your thumb and index finger, with moderate pressure. If you are a weight-lifter, use less than moderate pressure. The idea is for it to be tight, with little slop, but not so tight for it to burn out bushings.

  3. #3
    Join Date
    Dec 2004
    Peoria, IL

    Default Re: Serpentine Belt tension?

    if your 97 5.7 is anything like mine, the "idler" pulley will be the easiest to adjust the tension with. trust me, with only you doing the job, you will not be able to over tighten the belt tension. Unless as stated above you are a weightlifter. I use one hand to pull up on the idler pulley as hard as I can, and one hand to tighten it's bolt. Works like a charm. I don't think you can over tighten a serpentine belt. Cause on GM cars they have that spring loaded tensioner, and it it a B**** to loosen, so that serp belt is tight on those cars!

Similar Threads

  1. Serpentine Belt P/N?
    By Dshow in forum Mercruiser I/O & Inboard Engines & Outdrives
    Replies: 6
    Last Post: March 7th, 2010, 02:17 PM
  2. Serpentine Belt
    By richardreyn78818 in forum Mercruiser I/O & Inboard Engines & Outdrives
    Replies: 5
    Last Post: November 21st, 2008, 05:50 AM
  3. 4.3 Mercruiser Serpentine Belt
    By MRA in forum Mercruiser I/O & Inboard Engines & Outdrives
    Replies: 2
    Last Post: July 6th, 2008, 11:26 AM
  4. Convert V-belt to Serpentine
    By topdog in forum Mercruiser I/O & Inboard Engines & Outdrives
    Replies: 7
    Last Post: May 12th, 2008, 08:29 PM
  5. how do you loosen serpentine belt on volvo i/o
    By longpoint in forum Volvo Penta I/O & Inboard Gas Engines & Outdrives
    Replies: 10
    Last Post: February 18th, 2008, 02:53 PM
  1. iboats Forum Directory - Over 100,000 forum posts organized by topic