Alternator is slow to start charging

[SailFastTri]

Lately my alternator doesn’t kick in to charge the battery until it’s been running for 15 minutes or more, maybe even 30 minutes (no pattern). Connections are all tight and clean. It’s a Valeo 60A OEM alternator with internal regulator. Clues or suggestions would be appreciated?

[atoll]

Originally Posted by SailFastTri

Lately my alternator doesn’t kick in to charge the battery until it’s been running for 15 minutes or more, maybe even 30 minutes (no pattern). Connections are all tight and clean. It’s a Valeo 60A OEM alternator with internal regulator. Clues or suggestions would be appreciated?

check the fan belt tension it may be slipping un noticed,also rev the engine above 1200 rpm most alternators dont have enough field current to energise till 1000 rpms reached

[SailFastTri]

@atoll, it looks like it's turning. No squealing. Definitely revving the engine high enough. Will check belt tension by feel tomorrow.

[atoll]

Originally Posted by SailFastTri

@atoll, it looks like it's turning. No squealing. Definitely revving the engine high enough. Will check belt tension by feel tomorrow.

also check the blue grey? field wire is getting voltage to the alternator it is the single wire terminal block connector connected into the back of the alternator.

it should be the same voltage as the battery, if there is a bad connection and no voltage then the alteranator will not start to charge this acts as the "sense" wire,disconnecting it will stop the alternator from charging

[SailFastTri]

It turns out my problem was a loose belt. Never had that become an issue before without a squealing sound but this time was quiet. Thanks for the tips.

[Mattm]

If it's a v belt check the pulley and how deep the belt is falling into the valley, could be a worn belt or a worn pulley or both. If the belt bottoms out in the V it may not squeal

[Suijin]

I change my belt pretty regularly (every 3-400 hours, or sooner if it looks iffy). Cheap insurance.

[travellerw]

Originally Posted by SailFastTri

It turns out my problem was a loose belt. Never had that become an issue before without a squealing sound but this time was quiet. Thanks for the tips.

I'm wondering if you have a Tachometer? On our boat, the Tach will start doing strange things once the belt becomes loose (like a bouncing needle).

[Cheechako]

Have you tried revving it up a bit after starting? Sometimes it takes that to get the regulator to kick in...

[Mattm]

Originally Posted by Suijin

I change my belt pretty regularly (every 3-400 hours, or sooner if it looks iffy). Cheap insurance.

have you ever checked he pulley groove? these do wear out, especially when people buy belts that are advertised as extended life

[Suijin]

Yup every time I change the belt, which is nothing fancy just a standard NAPA belt.

[turtleofdart]

Originally Posted by Cheechako

Have you tried revving it up a bit after starting? Sometimes it takes that to get the regulator to kick in...

My friend who is a first class electrician advised me to short out the terminals on the charging light to get the charging to kick in...i do this regularly now....

[travellerw]

Originally Posted by turtleofdart

My friend who is a first class electrician advised me to short out the terminals on the charging light to get the charging to kick in...i do this regularly now....

You know.. You could actually put a light across those connections (tied to an ignition switch or key)!

[atoll]

Originally Posted by SailFastTri

It turns out my problem was a loose belt. Never had that become an issue before without a squealing sound but this time was quiet. Thanks for the tips.

it always pays to check the simple stuff first!