This video is sponsored by INA.
A shop calls. They need an alternator ASAP. To ensure that the alternator has a long life, be sure to ask the shop if the alternator has a decoupler pulley.
When you’re looking at parts these days, you’re seeing a lot more four-cylinder engines out there. Automakers are doing that for efficiency so their fleet fuel-economy numbers go up.
But it also means that drive belts, tensioners and alternators are taking a lot more abuse.
With a four-cylinder, there’s a lot more gap between the power pulses. This means that the crankshaft is speeding up and slowing down between those pulses. This is known as “rotational irregularity” to engineers.
What does that mean to your store and your customers? A lot of the OEMs and suppliers have introduced something called the decoupler pulley. This decouples the alternator mass from the drive-belt system, and it absorbs a lot of these rotational irregularities that come from the crankshaft.
It’s a wear item, in a way. Decoupler pulleys either have ramp clutches on them, or some of them even have springs inside that wear out over time.
So, when you get a customer at your store asking for a new alternator, ask them, “Does it have a decoupler pulley?” If it does, make sure the alternator you’re selling them has a decoupler pulley and the technology matches. If it doesn’t, sell them a new decoupler pulley.
