Nothing Special's '71 Bronco

[ArdWrknTrk]

Oh, and I meant to add why I'm looking at the flywheel ring gear in the first place. For quite a while if I let off the key when the engine fires briefly, if the engine dies and I try to start it again too soon it will just grind. "Too soon" means not everything is done spinning. I think the engine is stopped when this happens, but the starter is still spinning. I don't know that this is unusual or has anything to do with chewed up ring gear teeth (although the grinding certainly could be what caused it). But I mention it because it's not something I've typically experienced with other vehicles.

The bigger problem is that a handful of times the starter just grinds when I try to start the engine even if nothing was spinning when I first turned the key. This doesn't happen very often. When it happens most of the time it will crank the engine on the 2nd or 3rd try. Of the times when it hasn't worked, most of the time I was on enough of a hill to roll it and pop the clutch to move the ring gear enough to get fresh teeth lined up and it would then start. But there was one memorable time on my first trip to Moab where I couldn't get it to roll (coming down from Top of the World) and i ended up having to use my winch to bump the engine to get fresh teeth lined up.

I've been living with it since then, not wanting to dig this far in if I didn't have to. But as I said above, when I was this far in it seemed like a good time to get this taken care of.

Bob, I don't have an answer for you but came to say I've had a similar situation since I swapped flywheels and installed my 5-speed.

Blew the nose off a few of the older rocking pole style starters then switched to pmgr.

Even those didn't last until I relieved the centering boss and shifted the starter tighter into mesh.

I still have a torn up ring gear. And my truck starts like a Chevy that needs a shim, but at least it engages every time.

You're absolutely right the time is now. "while you're in there"

Hope you find a solution, and more importantly the reason for your troubles.

 

[mat in tn]

Oh, and I meant to add why I'm looking at the flywheel ring gear in the first place. For quite a while if I let off the key when the engine fires briefly, if the engine dies and I try to start it again too soon it will just grind. "Too soon" means not everything is done spinning. I think the engine is stopped when this happens, but the starter is still spinning. I don't know that this is unusual or has anything to do with chewed up ring gear teeth (although the grinding certainly could be what caused it). But I mention it because it's not something I've typically experienced with other vehicles.

The bigger problem is that a handful of times the starter just grinds when I try to start the engine even if nothing was spinning when I first turned the key. This doesn't happen very often. When it happens most of the time it will crank the engine on the 2nd or 3rd try. Of the times when it hasn't worked, most of the time I was on enough of a hill to roll it and pop the clutch to move the ring gear enough to get fresh teeth lined up and it would then start. But there was one memorable time on my first trip to Moab where I couldn't get it to roll (coming down from Top of the World) and i ended up having to use my winch to bump the engine to get fresh teeth lined up.

I've been living with it since then, not wanting to dig this far in if I didn't have to. But as I said above, when I was this far in it seemed like a good time to get this taken care of.

is the ring gear not part of the flywheel?

[ArdWrknTrk]

is the ring gear not part of the flywheel?

No. They are heat shrunk on.

Unfortunately one side is beveled so you can't just flip it over to get clean teeth.

A new ring gear isn't very expensive but you need a torch and it's a lot of work to install a $20 part.

[Nothing Special]

is the ring gear not part of the flywheel?

I could be wrong, but as I understand it, most ring gears are press-fit (or more often heat-shrunk) onto the OD of the flywheel. If I'm wrong then obviously replacing the ring gear will mean replacing the entire flywheel.

[Nothing Special]

Bob, I don't have an answer for you but came to say I've had a similar situation since I swapped flywheels and installed my 5-speed.

Blew the nose off a few of the older rocking pole style starters then switched to pmgr.

Even those didn't last until I relieved the centering boss and shifted the starter tighter into mesh.

I still have a torn up ring gear. And my truck starts like a Chevy that needs a shim, but at least it engages every time.

You're absolutely right the time is now. "while you're in there"

Hope you find a solution, and more importantly the reason for your troubles.

Thanks. That definitely give me more to think about.

[Nothing Special]

Thanks. That definitely give me more to think about.

OK, finally a little progress. It took me a little while to be confident in what parts I needed to fix my starter gears. In the end I decided on going with all stock Bronco 302 stuff. Then it took a while to get the parts in. For some reason auto parts stores don't always have everything you need for a project on a 51 year old truck!

But this week I finally got to removing the old ring gear. That went easy enough. I cut most of the way through it with a cut-off wheel in my Dremel, then whacked it with a chisel a couple of times.

Getting the new ring gear on was a bigger chore. It had a pretty sharp edge on the inside, so I had to grind a better lead-in on it. Then I heated it with the oxy-acetylene torch at work until it would start on. Finally a bunch of whacks with a big hammer and a punch and it was seated on the flywheel.

So today I put the flywheel back on, as well as the clutch, bellhousing and starter. Laying on my back while lifting all of those things into position tired me out enough that I decided to call it quits for the day rather than try to put the trans back in (which is the next step).

I did try turning it over with the starter and it cranked over nicely, with no weird noises or anything. So far so good!

[grumpin]

OK, finally a little progress. It took me a little while to be confident in what parts I needed to fix my starter gears. In the end I decided on going with all stock Bronco 302 stuff. Then it took a while to get the parts in. For some reason auto parts stores don't always have everything you need for a project on a 51 year old truck!

But this week I finally got to removing the old ring gear. That went easy enough. I cut most of the way through it with a cut-off wheel in my Dremel, then whacked it with a chisel a couple of times.

Getting the new ring gear on was a bigger chore. It had a pretty sharp edge on the inside, so I had to grind a better lead-in on it. Then I heated it with the oxy-acetylene torch at work until it would start on. Finally a bunch of whacks with a big hammer and a punch and it was seated on the flywheel.

So today I put the flywheel back on, as well as the clutch, bellhousing and starter. Laying on my back while lifting all of those things into position tired me out enough that I decided to call it quits for the day rather than try to put the trans back in (which is the next step).

I did try turning it over with the starter and it cranked over nicely, with no weird noises or anything. So far so good!

That’s good progress!

[Gary Lewis]

OK, finally a little progress. It took me a little while to be confident in what parts I needed to fix my starter gears. In the end I decided on going with all stock Bronco 302 stuff. Then it took a while to get the parts in. For some reason auto parts stores don't always have everything you need for a project on a 51 year old truck!

But this week I finally got to removing the old ring gear. That went easy enough. I cut most of the way through it with a cut-off wheel in my Dremel, then whacked it with a chisel a couple of times.

Getting the new ring gear on was a bigger chore. It had a pretty sharp edge on the inside, so I had to grind a better lead-in on it. Then I heated it with the oxy-acetylene torch at work until it would start on. Finally a bunch of whacks with a big hammer and a punch and it was seated on the flywheel.

So today I put the flywheel back on, as well as the clutch, bellhousing and starter. Laying on my back while lifting all of those things into position tired me out enough that I decided to call it quits for the day rather than try to put the trans back in (which is the next step).

I did try turning it over with the starter and it cranked over nicely, with no weird noises or anything. So far so good!

Yes, that's good progress. Well done!

[Nothing Special]

Yes, that's good progress. Well done!

More progress today. I got the transmission back in. It takes a lot less time to type that than it does to actually do it! That wraps up the starter gear replacement (since the trans wouldn't have come out if I wasn't doing that) and it brings me to where I can actually start on the real project.

[Gary Lewis]

More progress today. I got the transmission back in. It takes a lot less time to type that than it does to actually do it! That wraps up the starter gear replacement (since the trans wouldn't have come out if I wasn't doing that) and it brings me to where I can actually start on the real project.

Well done! Now for the real project.