The five-second shifting rule
What Chris sees on the bench
Take a 1017-004 that came in from Connecticut. The forward clutches weren't too bad, though you could start to see score marks on the pressure plate. The pump had a little scoring and a few scratches, but nothing bad. The reverse clutches were blown up and the springs were taken out with them. That's the ski boat dilemma: save the skier or blow up the reverse clutches. It happens all the time.
Why it matters
The reverse planetary spins fast. The reverse planetary gears spin about 1,000 rpm for every 100 rpm that comes in. That's why you can't run these cast-iron transmissions in reverse to go forward. It smokes the planetaries, and it'll ruin the transmission quickly. There's more on that in running reverse for forward.
Engine speed matters when it goes into gear, too. Our test stand runs at 535 rpm and can also run at 864. If you leave a boat idling anywhere around 600 to 700 rpm, you'll get a lot of bang when it goes into gear.
Fix and prevention
Give the shifter time. Go from forward to neutral to reverse over five seconds instead of banging it into hard reverse. If you drive a ski boat, that's the habit to build, because saving the skier with a hard reverse shift is exactly how the reverse clutches get blown up.
When to call
If you've lost reverse, see lost reverse for what that failure looks like, or call (804) 333-3677, Monday through Friday 9 to 3 Eastern. You can also email sales@halemarine.com.
Related reading: lost reverse: shattered reverse clutches.