Starter Bendix problem

Park_W

OK, gang ... I need some ideas here. Just finished a rebuild of the engine in my '51 Hornet, and there's an issue with the starter drive that wasn't there before. The starter wasn't touched during the process other than being removed during the engine work. Problem is that the pinion doesn't kick out quite far enough when the engine starts, so sits there and "sing"s lightly, just barely touching the back side of the flywheel teeth. The 'kicked out" position of the pinion is exactly 5/8" from the face of the "snout" of the starter (MCH-6109). Back side of the ring gear is 1.596 from the back side of the rear engine mount plate. All new engine main bearings, and the crankshaft end play is on spec.

I've removed a little end play in the starter shaft resulting in the shaft's protruding a bit further, but the gain was miniscule and didn't fix the psoblem. I've changed out the barrel and pinion assembly with a new one, hoping that the "at rest" position of the pinion would be a little further back, but no luck there. Any ideas out there?

[Deleted User]

Those starters will go in two ways. The mounting bolts look like they are in line with the shaft but are not. One way is fine 180 degees and teeth dont engage. Maybe this is what happened ,
Roger

Park_W

Roger, the teeth are engaging fine. That's not the problem.

corangerroadrunnercom

It's got to be something you did if it worked before. I'm not trying to be a smart as% ,but it looks like a lot of space to make up. Could the flywheel be on backwards? Jim

Park_W

Ken, the mounting stud issue is not the problem ... the gears are meshing properly. You could say the problem is "longitudinal, not lateral." And the mount plate is not warped ... that's an illusion in the photo. I've put a straight-edge on it. The problem is the fore-and-aft position of the starter pinion relative to the ring gear. Aside from the problem itself, It's puzzling me why this problem is there at all ... it didn't exist before the teardown and reassembly. It's like the flywheel is further to the rear than it was. If no solution is found, I may put a gasket between the rear mount plate and the block, to move the mount plate rearward a little. I'm also studying the Bendix drive construction to see if a small change might be achieved in the "at rest" position of the pinion on the shaft. But again, what caused this issue anyway?

Now, back to the mounting studs, I think you're incorrect about their role in precise positioning of the starter. The starter's position on the mount plate is fixed primarily by the four protrusions on the starter's mount plate ... they're what positions the starter precisely in the engine's rear plate hole. The starter mounting studs are actually a rather loose fit in the recessed bell housing holes ... not a precise fit at all. Even the studs having raised ridges so they fit snugly in the engine mount plate still fit loosely in the starter's mount plate holes. But I do have the original studs and have always used them. That said, the bolts you see in the photo are metrics, a size slightly larger than 3/8, and they help to hold the starter in proper position better than the loose-fitting 3/8 studs do. Not sure if I'll use them when putting everything together for actual service ... probably not.

Park_W

From above: "All new engine main bearings, and the crankshaft end play is on spec."

Park_W

OK gang ... how's this? About 1/4" clearance now between pinion and ring gear. I got this by doing what I prefer not to do ... compensating for the problem rather than finding and fixing the real source of it. When the pinion and barrel assembly is "kicked out" by the engine's starting, it moves back until the heavy spiral spring at the "bottom" of the barrel encounters the fixed part of the Bendix mechanism. So I shortened this heavy spring by removing about 1/2 turn of it. Voila! I'm not going to worry further about why the pinion ended up being so close to the ring gear when I reassembled everything. Regarding the crankshaft/flywheel position, Eastern Director John Upchurch measured the mount plate-to- flywheel dimension on a spare 262 he has, and mine did agree with that.

SuperDave

I have had similar problems when using a run in stand with no bell housing. Bolting a belhousing on cured the problem. Must be some small flexing of the -plate.. good Luck Park.

Park_W

Dave, I had the bell housing on this rig earlier, and it didn't change anything.

[Deleted User]

Gremlins ? ?

hudsonguy

Park,

Coincidentally, I'm having the same problem with a starter right now, although the situations are different.

Yesterday, on my '49 262 engine, I installed a newly rebuilt starter that was done by Ken Warner at Classic Generator. He did a beautiful job, everything appears to be done right. But now after starting, it seems that the new starter drive is not moving out of the way enough of the spinning flywheel, and it chatters like crazy as the drive gear teeth are being clipped by the ring gear. If I shut it off, and restart it everything's fine for a mile or two, and then the chatter returns, and I'm making a beeline for home.

I'm using the proper studs, ring gear is in great shape with no changes there, etc. I've emailed Ken (who seems to be a great guy) for any suggestions. I'm wondering if the new drive is just too stiff, and needs some lubrication? Unfortunatly, he installed a different drive (like on a Ford tractor), so I don't have the option of shortening the spring like you did.

Does that drive arbor come off the shaft with a small puller? If nothing else, I can always swap the drive with one from another starter I've got. I'd really like to make the new starter work, as it is a 12v conversion.

Any thoughts or suggestions are welcome, I appreciate the help, and since we're leaving for Kalamazoo on Thursday for the Central Regional, I need to get this resolved one way or another.

Thanks to all!
Doug