GEAR REDUCTION STARTER CAUSED RING GEAR FAILURE

[Shannon Boal]

Two weeks ago, the starter failed on the red Series V. Deb cranked it at the gas station near the Invasion Hotel, and it made the sound of gears stripping. So, we push started it for the rest of the event and the drive home. Last Monday, I dummied up a block and flywheel with a Lucas starter, and measured the gear mesh dimensions. The Lucas starter pulls it's drive from the rear of the vehicle into the ring until the drive rides in the center of the ring gear. It engages all of the teeth. Today, I pulled the starter, a Denso type with an adapter on it. I found it to be properly mounted, but the ring gear is a mess of sharp metal. I measured the throw of the Denso type, and observed the wear pattern on it's drive teeth. It throws from the front to the rear. It engages only about one-fourth of the ring gear teeth. The wear pattern on the starter drive gear shows a pattern about 5/32" wide. It does not throw nearly far enough to center in the ring gear. The ring gear failure was caused by the lack of throw, compounded by the mounting depth of the starter being too shallow......(by about the depth of the "adapter"). More work is needed to find out how to optimize the starter mounting depth, the starter throw, and the depth at which the starter motor is energized.

 

[DanR]

Shannon, You may have just begun finding the cause.... Hope you can get it resolved sufficiently and a permant manner.

Was the starter I gave you any good?

Please keep use posted on your progress.

Sory I was of no better help,

 

[Shannon Boal]

Here is a photo, showing wear on starter gear:

 

[Shannon Boal]

Shannon, You may have just begun finding the cause.... Hope you can get it resolved sufficiently and a permant manner.

Was the starter I gave you any good?

Please keep use posted on your progress.

Sory I was of no better help,

More of the story....Dan gave me a good lucas type starter. It works fine on the dummy motor, and, because it uses the rear side of the ring gear, it works in the car. Hot cranking may be another story, but we are pretty good at push starting!

 

[spmdr]

I converted a Denso starter from a Ford V8

to an Alpine, some time ago.

As I recall, there were spacers that needed

to be in the Right place.

And/or different length gears.


I wouldn't go Back to an OEM Alpine starter

...Except for TEMP use...push starting is for

the YOUNG!

DW

 

[Acollin]

You might give this a try if you happen to have a hand crank:
For a few laughs, I started my series V with the hand crank. I was shocked how easily it fired up. A lot easier on the lung capacity than the push.
Hey SPMDR, why not go back to an oem starter?

 

[DAVID LAWLER]

Just a couple of caution comments:

1. I had fine success with the Orange Blossom - Series V. Easy bolt up and the Denso type starter has been in for three years with no issue and works quite perfectly - great improvement.
2. Last year there was someone with an issue where that type of starter engaged too much ! From speaking with the starter supplier, I learned that a shim is, not often, but some times required because of the too much engagement issue with most of the LBCs.
3. It may pay to look at the machining of the block where the starter mounts. Could that thickness be be varying ? The original starter has so much throw that it most likely would not matter. Also could the new starter mounting adapter be varying? The difference between too much throw and your condition of too little is a huge dimensional variation. If you have any engine blocks or parts to compare the item too, it might point to the source of the problem, and thereby a solution.
4. Side note - Kate's Tiger also has a Denso type starter - no shims - no issues - works quite well.

Dave Lawler

 

[spmdr]

Acollin, Hand cranking an Alpine is yet another lost (for Good reason) art/skill.

BUT, IF I Daily drove an Alpine, I would have a crank...maybe.

Here is why you want a geared Starter:

Starter disengages too soon

With retirement and a move from Houston to N. Colorado, I have not given my Sunbeam IV much attention for a good while. Now that I have some time to drive it, I am having starter problems. The starter cranks well, but the instant the engine fires, the starter disengages the flywheel and whirs...

forum.sunbeamalpine.org

DW

 

[junkman]

Did you reverse the ring gear so the engagement side of the teeth are facing the starter? That and the correct depth should take care of it.

 

[Shannon Boal]

You might give this a try if you happen to have a hand crank:
For a few laughs, I started my series V with the hand crank. I was shocked how easily it fired up. A lot easier on the lung capacity than the push.
Hey SPMDR, why not go back to an oem starter?

The crank hole in the front bodywork is high/low, so I gotta correct that, but YES, I want that capability!

 

[Shannon Boal]

Just a couple of caution comments:

1. I had fine success with the Orange Blossom - Series V. Easy bolt up and the Denso type starter has been in for three years with no issue and works quite perfectly - great improvement.
2. Last year there was someone with an issue where that type of starter engaged too much ! From speaking with the starter supplier, I learned that a shim is, not often, but some times required because of the too much engagement issue with most of the LBCs.
3. It may pay to look at the machining of the block where the starter mounts. Could that thickness be be varying ? The original starter has so much throw that it most likely would not matter. Also could the new starter mounting adapter be varying? The difference between too much throw and your condition of too little is a huge dimensional variation. If you have any engine blocks or parts to compare the item too, it might point to the source of the problem, and thereby a solution.
4. Side note - Kate's Tiger also has a Denso type starter - no shims - no issues - works quite well.

Dave Lawler

1) Block dimensions, flywheel dimensions and variations in crankshaft end-float are not suspect, have two setups (engine on stand & engine in red car) with same problem. Common denominator is this starter....
2) Gotta disassemble starter and look at issues there. Rebuilder's catalog sources can help with variables there. A shim determines the position of throw where the starter motor energizes; if the event occurs before complete meshing occurs more or less shimming may be indicated.
3)Prime suspect is the adapter; it moves the starter too far out of the engine block. I may grind, file, machine that thinner, adding another 3/16" of gear engagement. With a new ring gear, that would probably work fine.
4) But, trying to get the whole story, and advance the good of the order. So, want to come up with a fool-proof solution, worthy of the giants upon whose shoulders I stand.......

 

[Shannon Boal]

Did you reverse the ring gear so the engagement side of the teeth are facing the starter? That and the correct depth should take care of it.

Solution includes new ring gear.....the situation is that this starter is WAY off on depth. If you look carefully at the photo, the wear pattern shows an engagement of maybe 5/32", only a fraction of the ring gear width.

 

[Shannon Boal]

A cropped photo showing the gear tooth wear pattern:

 

[PROCRAFT]

Here's some more on this: When I did Nicks V6 Alpine i used up two starters after measuring I machined a spacer to move the starter back to correct the engagement, it seems there are different flywheels offset thickness????

 

[Shannon Boal]

Not sure about the flywheel differences, looks like they all interchange. I plan Monday to post measurments of ring gear position/ depth. It looks now to me that the starter has a badly designed adapter....with another 1/4" of depth/ engagement, there would not have been a problem. Of two Gear reduction starters I have installed, there are at least two types of adapters. Will try to verify all that, and go from there.

 

[Jay Laifman]

As to the original starter, my dad used to joke about the knob that we can turn to unlock a locked up starter. He pointed out that the Germans and Japanese didn't have this "feature" - because they made their starters work without jamming in the first place.

 

[Toyanvil]

The starter gear looks normal, they are made with ramps to help them engage, that does not look like wear. I would compare the starter gear you have to a Sunbeam one, number of teeth and size, remember the Lucas starter pulls, so the ramps will be on the other side. And check that the starter motor is working right, full throw on the gear. But I also think junkman is right, the flywheel should also have ramps that help the starter gear engage. That said, I have turned around flywheel rings that were damaged that had ramps on both sides.
link to new gear new starter gear

 

[Shannon Boal]

The starter gear looks normal, they are made with ramps to help them engage, that does not look like wear. I would compare the starter gear you have to a Sunbeam one, number of teeth and size, remember the Lucas starter pulls, so the ramps will be on the other side. And check that the starter motor is working right, full throw on the gear. But I also think junkman is right, the flywheel should also have ramps that help the starter gear engage. That said, I have turned around flywheel rings that were damaged that had ramps on both sides.
link to new gear new starter gear

Not the point, the point is this: that wear pattern shows that the gear does not engage sufficiently in the ring gear, hence the failure. The starter gear is very hard, the ring gear is not. If you read my post all of this is addressed. Not sure that the bevel on the ring gear makes much difference....

 

[Shannon Boal]

Have done a pretty good job measuring and documenting, and now having good conversation with the nice folks who built this starter. Will report details.

 

[Shannon Boal]

Shipping this starter to manufacturer tomorrow. Will verify all measurements. He knows his business, and I learned something from him. When the starter drive gear engagement is insufficient, it causes the starter shaft to deflect under cranking load. This starter worked OK for 2700 miles, but it was weak....a failure waiting to happen. This is an opportunity to make these better, and he has a plan for that.