jfilc
New Member
How do you change an alternator belt in a 454 with an alernator, fresh water pump pully amd a tension pully?
Changing Alternator Belt
- Thread starter jfilc
- Start date
- Nov 12, 2006
- 5,334
- Boat Info
- 1999 Sea Ray 330DA
Twin 7.4 MPI (310 propshaft HP) V-drives
- Engines
- Twin Mercury Marine marinized 7.4L L-29 V8s
Cast iron block w 4-bolt mains
What year engine? V belts or serpentine?
If you have a single serpentine drive belt, this might work:
The tension pulley is manually adjustable. Using and open end wrench, loosen the retainer nut. I think it's 5/8. The pulley will drop down and the belt will be loose.
Remove and install new belt.
With a small wrench turn the end of the stud for the tension pulley. I think that's a 1/4" hex. As you turn the stud, the pulley will slide up it's track and tighten the belt. When tight enough, tighten the 5/8" retainer nut with an open end wrench.
Best regards,
Frank
sprink56
New Member
- Oct 28, 2008
- 1,288
- Boat Info
- 1979 255 Liberator
- Engines
- twin Mercruiser 450 HP I/O on Bravo I Drives
It depends on the arrangement. With mine I must remove one of the raw water pump hoses to change the belts.
Mr Salt
New Member
- Jun 14, 2008
- 632
- Boat Info
- Raymarine/Raytheon electronics, Sat TV, Yacht Controller
- Engines
- 2003 Caterpillar C-12s Twin Disc Transmissions
Gently ???
- Nov 26, 2006
- 7,628
- Boat Info
- 2008 44 Sedan Bridge
- Engines
- Cummins QSC-500's
Straight Drives
The proper tension on the serpentine belt is such that, along the longest stretch of the belt, moderate tension with your finger will displace the belt about 1/4" when depressed near the center of said stretch.
J Levine
New Member
- Oct 5, 2006
- 753
- Boat Info
- 1995 Sea Ray 370 Sundancer
- Engines
- Mercruiser 7.4L Blue Water inboard V Drives
On my 454's, which have v belts, you have to remove both the raw water belt by loosening the idler as Frank C described above and then you have have to remove the pulley from the crank shaft in order to make enough clearance from the water pump pulley to get the belt off the crank pulley. The pulley comes off with three bolts and is easy to remove.
