Running alternator as a motor for redundant starter motor and EOC

[ShadeTreeMech]

...depending on how strong it is, I want one!

[Old Tele man]

...bet the drive belt for that alternator co$t$ more than any fuel saving$ (ha,ha)!

[comptiger5000]

I don't know that it would be powerful enough to crank the engine on its own, but it could certainly assist the starter for faster startups.

Old Tele Man - Don't joke about the belt cost for the wide ones that'll handle lots of power. The fairly long 7-rib serpentine belt for my Jeep is about $55, unless you buy the cheapo Autozone belt (wouldn't trust it though).

[ShadeTreeMech]

Originally Posted by Old Tele man

...bet the drive belt for that alternator co$t$ more than any fuel saving$ (ha,ha)!

I've seen the drivebelts on industrial machinery last so long they need changing from age. And this is machinery moving literally tons of green lumber and needing to suffer constant start stop cycles and surviving the torque of a 480v motor.

They bought their belts at the local auto parts stores. The belts were just a variety of v belts and serpentine belts. The truly extreme applications may use 3 v belts in tandem, but the amount of torque they had to withstand is truly mindboggling.

IIRC the serpentine belts popular on newer vehicles have Kevlar threads in them to increase their strength and reduce the stretching common on normal belts. I'm curious about how many horsepower is being transferred from a serpentine belt in a vehicle running down the road with the AC blasting and the headlights on? A significant amount I'll wager. And under less than ideal conditions for a belt, with the heat of the radiator blasting it day in and day out.

[Phantom]

Saand check out How To Rewind an Alternator for some thinking.

[Old Tele man]

...I know about belts, one of our two FMC-manufactured Field Dynamometers at the U.S. Army Proving Ground, Yuma, AZ, used "belt" coupling between it's TANK engine and its mongo-TRUCK transmission...used something like 10 or 12 "matched" V-belts, which all had to be changed 'en-masse' when more than one or two failed.

...of course, the 115-120°F summer desert temperatures didn't "hel" service life either!