Rick's Free Auto Repair Advice
Repair Topics > Start stop systems > Does Start Stop Wear Out your Starter

Does Start Stop Wear Out your Starter

Will the new start stop wear out your starter?

Most people think a start stop starter wears out quickly. Well, eventually yes. But not as quickly as you think considering how many more cycles they go through on a daily basis. Traditional starters are designed for 50,000 starts. Stop start starters are designed for 200,000 or more starts. Here’s why.

Start stop starters are gear reduction starters

Start stop starters are designed with gear reduction

gear reduction start stop starter

gear reduction start stop starter

so the motor spins at the same speed but the start motor turns at a much slower speed than a traditional starter. Why is that important? Because 90% of the carbon brush wear in a traditional starter occurs during coast down after the starter is turned off. Get that? The majority of the brush wear does not occur during cranking. It occurs as the starter motor spins down. With a gear reduction starter, the cranking and the coast down speeds are much lower than a traditional starter so the coast down time is much shorter, leading to far less brush wear.

Start stop starters use a different brush composition

Traditional starters use a carbon brush on springs. Over time, the carbon brush wears a groove into the motor’s commutator. Brush and commutator wear cause starter failure. But the brushes in a start stop starter use a different composition of carbon and copper to obtain longer life and require less pressure against the commentator.

Start stop starters use different bearings

Traditional starters use sintered bronze oil impregnated

sintered brass bushing

Sintered Bronze Bearing

sleeve “bearings” to support the motor shafts. Sintered bearings don’t actually spin like a traditional ball bearing. Instead, sintered brass sleeves are made from ground up brass that’s compressed under high pressure to form a sleeve.

sinterend bronze bearing

Notice the pores in the sintered bronze bearing. That’s where the oil hides out

The sleeve is then place under high vacuum and oil is added. The oil is literally sucked into the voids between the ground up brass particles and it’s that oil that provides lubrication. Unfortunately, sintered brass sleeve bearings down self-lubricate well at colder temperatures.

So start stop starter manufacturers use needle bearing instead.

Start stop starters use different solenoids

In a traditional starter, the solenoid does double duty; it moves the pinion gear into mesh with the flywheel teeth while also acting as the power switch to deliver battery power to the starter motor. Start stop solenoid have only a single job; move the pinion gear into mesh with the flywheel. The power switching is done by other means. This eliminates the arcing and pitting on electrical contacts in a traditional starter.

Instead of using the solenoid to switch power, start stop starters use a dedicated power switching mechanism, so if it fails, the entire starter doesn’t require service. Since the solenoid doesn’t have to hold contacts against one another during cranking, the solenoid in a start stop starters requires far less power to operate, which also reduces overall current requirements for cranking.

Start stop starters integrate with piston position

In a start stop system, the fuel injectors fire during the middle of a complete revolution of the crankshaft, rather than waiting for a full revolution. So a piston can reach top dead center and the IGN system can fire earlier, shortening crank times and crank energy.

There are many start stop starter designs

Beefed up traditional starter

Start stop starters that are simply beefed up start stop starterversions of a traditional starter. They’re have dual layer brushes, a different pinion gear spring mechanism that reduces ring gear and flywheel wear by almost 90%.

Tandem solenoid start stop starter

Where a traditional starter can only engage with the flywheel at zero flywheel rotation, a tandem solenoid design can re-engage with the flywheel from 0-RPM to as high as 600-RPM. That shorten restart time.

Permanently engaged starter

The weak link in the other two starters is the mechanism that thrusts the pinion gear into the flywheel. A permanently engaged starter eliminates that entire mechanism by permanently engaging the pinion gear with the ring gear on the flywheel. The pinion gear rotates the entire time the engine is running and is connected to the start motor with a one way clutch. When the start motor needs to restart the engine, it’s instant—totally eliminating pinion gear engagement lag time.

©, 2019 Rick Muscoplat

Posted on by Rick Muscoplat

Categories

Tags



Custom Wordpress Website created by Wizzy Wig Web Design, Minneapolis MN