Starter Problems - Heads Up

[tmontague]

I've been having issues the past 2 weeks where my starter pinion gear would not engage the ring gear on my flywheel intermittently. The starter ends up spinning freely and engagement connects and then disconnects. It is better in the morning when everything is cold but much worse once warmed up.

Thinking off the top of my head that it was a failing solenoid, I picked up a used starter from a local recycler for $50 which was from a Yaris but was fairly new and it appeared to be an aftermarket replacement. Due to the aftermarket pinion gear being about 1mm thicker it caused a nasty rattle in my transmission when the engine was running so I had to swap my old pinion gear out from the old starter and attach it to the new starter motor and solenoid.

However once I did this the grind/rattle was gone, but the same intermittent engagement came back. This forced me to realize that the actual problem was a dirty/poorly lubed screw gear on the bendix of the starter. It was not seized, but it was sticky enough to fail engagement occasionally. It likely was better in the cold because starters tend to be more powerful in the cold and the power was enough to overcome the stickiness. It appeared that a bunch of clutch dust from the past 11 years had made its way into the starter bendix and mixed with the lube causing it to dry out. The bendix was actually not that stuck, but compared to the good one there was a big difference. It should be very slippery and you should see relatively clean grease/lube on the screw gear. If it isn't very slippery and moveable then it is likely causing an issue

The reason I am making a thread about this is because most people assume this is a solenoid failure. They take it to a shop and have a new starter put in which fixes the issue. This confirms to most people that the solenoid was in fact the issue. I likely would have been in the same boat had the new (used) starter pinion gear not been 1mm thicker than the oem one and caused a terrible noise.

If you google starter spinning but not engaging you never really find any articles or people talking about a bendix lack of lube issue. Everything points towards a failing solenoid, because when this happens usually it isn't intermittent.

However, if you search boating forums you realize that this issue is well known in outboard motors and there a a ton of videos just showing you to clean and re lube the bendix to fix the issue. This is likely because most people use their cars everyday and take it to a shop right away whereas boats have down time and are not as easy to find mechanics for. This leads to most people self diagnosing and fixing it themselves and therefore finding the real issue with the starter.

Bottom line, if you starter doesn't engage at all then yes, the solenoid could have failed. But if your starter spins but fails to contact the flywheel/pressure plate ring gear, then remove the starter and clean and re lube the bendix assembly. I used some lithium grease as a dry lube is recommended. A thin grease would likely also work as that is what seems to be on there from the factory.

I hope this helps save someone from buying a new starter