Gear reduction starters vs direct drive
 

Just about everyone on here is looking to reduce vehicle electrical consumption as part of some grander scheme or just simply reduce vehicle weight.
It seems like a lot of people on here are using direct drive starters.
The difference between direct drive and grear reduction are as simple as their name sake implies.
In Direct drive the motor and starter gear turn on the same shaft, at the same speed.
The gear reduction starter reduces the rpms coming off the starter motor before it reaches the starter gear, the gear spins slower but has lots more torque.

It may not seem possible but the more complex gear reduction starters are usually quite a bit lighter and smaller than their direct drive counter parts.
As you can imagine they use less power too.
The gear reduction starter allows the DC motor to spin much faster allowing it to develop more torque and run more efficiently than the direct drive starter that runs at half to 1/3 the speed of the more efficient gear reduction starter.

Gear reduction starters are more expensive. High end gear reduction starters with rare earth permanent magnets are even smaller and lighter.

My diesel takes 350 amps to turn over with its optional OEM style gear reduction starter. The standard direct drive starter took over 500 amps.
The gear reduction starter gives me almost 2 more inches of clearance to run the exhaust and its around half the weight. A rebuilt direct drive starter would have been up to $200, the new gear reduction starter was $250.
The gear reduction starter allowed me to switch to LiFePO4 batteries in my suburban, the weight savings from the starter and lead acid battery removal allowed me to lose over 100lb of vehicle weight.

The starter quit on my camaro back in 2010, so pulled the starter off and instead of running down to autozone and picking up some cheap $70 made in china pos direct drive, I ordered a powermaster rare earth, gear reduction starter from summitracing. Its claim to fame is its 1/3 the weight at 5lb and 1/3 the size and draws less than half the power of an OEM starter.
It cost around $200 and was made in U.S.A.
And it did all of those, the starter that came off weighed about 20lb. The high tech replacement was tiny compaired to what failed.
OEM starters are said to draw 300 too 400 amps, I measured this one taking in 200.
If they made one of these to fit my diesel I am confident it would start it.

So gear reduction starters:
are smaller
lighter
use less power
help your battery last a lot longer

Switching to a gear reduction starter may be able to help you:
reduce weight with starter its self
run a smaller battery to reduce or relocate weight
Make it possible to do an alt delete or solar assist
Jump start your car easier with cheap walmart jumper cables


With out gear reduction starters my LiFePO4 battery mod and relocation would have much more difficult to do.

1962 Mopar called and they want their starter back! That may be the best part of using a reduction gear starter, it will sound like a Mopar.

My ranger had one OE original. Nissan has been using them a long time. Customer told me once I was a thief for charging him $125 for a factory rebuilt gear reduction starter for a 280Z. He got 4 direct drive starters from advance and none of them lasted a week. Finally he comes back with his tail between his legs and begs me to fix his car. I told him I had not replaced 4 Nissam OEM re builds in 10 years. The cheap advance starters were \direct drives for a 4 cylinder engine. The 6 cyls used gear reduction. I think since the first 240Z was made in November 1969.

regards
Mech

The diesels gear reduction starter doesnt sound any different than the standard one.
But the one in the camaro has a distinct sound to it.

The only starter which worked decently in an old Suzuki Vitara which an uncle of mine formerly had was a gear-reduction one...

DD starters seem to be able to turn the motorover faster when warm, or in warmer weather.
But for actual cold starts in cold weather gear reduction is far superior.

No wonder a gear-reduction starter is the best option for Diesel engines, which not just have a higher compression to overcome but also the electric pre-heating devices which demand a high electrical load.

My "direct drive" starters are all geared down quite a bit when the pinion engages with the ring gear. Unless there's a starting difficulty they are on for all of three seconds. Meh.

But you have to carry the starter and battery around for tens of thousands of miles.

Its the easiest cheapest way I have found to cut 20 to 100 pounds with out giving anything up, like carpet and sound deadening materal or equipment and trim.

Hand-crank in a Diesel V8 might not be so easy as doing so in a random compact 4-cyl...

I once even lurked about adapting a pull-rope emergency start setup similar to the one used in outboard motors after having some trouble with the starter of a Pontiac Trans Sport, since it couldn't be bump-started due to the automatic transmission...

I was thinking about this today. I almost started a new thread when I thought to search. Thanks Oil pan 4 for starting a thread that already answered a bunch of questions!

Obviously, the gear reduction starter is superior for the reasons listed. But, what are the downsides to it though? I'm thinking maybe just cost at this point? What starter actually starts the engine faster, or is the difference imperceivable?

I understand what makes an engine harder to start. I'm just curious if these gear reduction starters will actually start an engine faster under the same conditions?

According to the diesel guys, under ideal warm starting conditions the straight drive starters fire the engine little faster over gear reduction starter.
But when the engine is cold, especially in winter, the gear reduction starters turn an engine over faster and get them to fire up sooner.

I only run gear reduction starters if there is a choice.

Nothing come for free, gear reduction reduces the initial/peak amp draw, but has to use the same energy to do the same amount of work, getting it spinning fast enough to fire on it's own.

The gear reduction motor runs at a more efficient higher RPM needed for the series-parallel wound motor to run more efficiently.
With better efficiency you do get something for free.
To say the gear reduction starter reduces amps is an understatement. It almost cuts the amp draw in half and cranking time is increased by a barely noticeable amount if at all.