Nothing Special's '71 Bronco

[FuzzFace2]

In my Home Movies thread Gary asked:

....

So, when do you head to Moab? What changes are you making before then? Not that this is the thread for that, but...

That may not be the thread for this, but this thread is, so...

The plan this winter / spring is a pretty major redo of the front suspension (among other things). The goal that started all of this is getting my radius arm mounts up higher. I lowered them a long time ago to fix my caster problems, but they are now a limiting factor. I high-center on them pretty frequently. But raising the radius arm mounts isn't something I can just do. I don't know if you're familiar with the concept of a snowball in projects like these??? So the way it goes is...

Raise the radius arm mounts to gain clearance.

.

But that won't get my U-joint angle low enough, so the other change planned is to rotate the differential forward to raise the pinion. In addition to improving the U-joint angle in the double Cardan joint at the transfer case that will also let me get the angle in the single Cardan U-joint at the diff closer to zero, which will help with the driveline vibration I now have in 4WD.

However rotating the axle forward will mess up my caster even more than just raising the radius arm mounts will. And remember, I did that to fix a caster problem originally. So the plan now is to cut the inner "C"s off the axle ends and turn them back to fix the camber.

Oh, and putting a skid plate under the transfer case seems like a good idea now too.

(I'm sure you have no experience with scope creep like that!)

You may want to rethink the "C" cup change after rotating the axle.

I say this because the caster & camber is built into the axle not the "C cups".

You raised & lowered the arms / C cups and that rotated the axle getting the angels back where the factory had them.

If you rotate the axle up for the pinion you have changed the caster / camber and moving the C cups back so they line up will do nothing to the caster / camber angels.

So besides maybe moving the C cups so they will line up with out binding when you rotate the axle pinion up you will need to cut the ends off the tubes and rotate them back where the factory had them and weld them back on.

Now you might be able to cheat by marking the tubes at the center section, pull them out / rotate them back to factory spec for caster / camber and weld them to the center section.

I know sounds easy right?

I just did not want you to go through the C cup change and find the truck was all over the road because the caster / camber angels were way off.

Dave ----

 

[Nothing Special]

.... If you rotate the axle up for the pinion you have changed the caster / camber and moving the C cups back so they line up will do nothing to the caster / camber angels.

So besides maybe moving the C cups so they will line up with out binding when you rotate the axle pinion up you will need to cut the ends off the tubes and rotate them back where the factory had them and weld them back on.

Now you might be able to cheat by marking the tubes at the center section, pull them out / rotate them back to factory spec for caster / camber and weld them to the center section.

I know sounds easy right?

I just did not want you to go through the C cup change and find the truck was all over the road because the caster / camber angels were way off.

Dave ----

One of us isn't understanding the other. When you talk about pulling the tubes out of the center section, rotating and welding them, that's exactly what I'm talking about doing to the inner Cs. I's just that I'm doing it at the outer end of the tube rather than the inner end. So it will definitely change my caster.

I think maybe what you're calling the C cups might be what I'm calling the radius arm wedges. I plan to cut those off, rotate the tubes and center section forward and weld new wedges on to rotate my pinion up. And yes, that would screw up my caster something fierce. But if I then cut off the inner C and rotate it back I can correct that.

I'm planning to cut the Cs off rather than pull the tubes out of the axle for a few reasons. From what I've heard, cutting the Cs off is easier than pulling the tubes out of the center section. And I'd much prefer to weld to the Cs than to the center section with its seals and bearings inside. Plus I need to move both the center section and the inner Cs with respect to the wedges. If I cut the Cs off I can position the pinion angle where I want it and then attach the axle in place before setting the caster. If I do it the other way, then I need to set the caster first (by positioning the tubes where I want them and welding the wedges on to keep it there) and only after that can I position the center section and weld it back to the tubes.

Anyway, that's the plan. I know IT will work. I'll find out if I'm able to execute it!

 

[Nothing Special]

.... If you rotate the axle up for the pinion you have changed the caster / camber and moving the C cups back so they line up will do nothing to the caster / camber angels.

So besides maybe moving the C cups so they will line up with out binding when you rotate the axle pinion up you will need to cut the ends off the tubes and rotate them back where the factory had them and weld them back on.

Now you might be able to cheat by marking the tubes at the center section, pull them out / rotate them back to factory spec for caster / camber and weld them to the center section.

I know sounds easy right?

I just did not want you to go through the C cup change and find the truck was all over the road because the caster / camber angels were way off.

Dave ----

One of us isn't understanding the other. When you talk about pulling the tubes out of the center section, rotating and welding them, that's exactly what I'm talking about doing to the inner Cs. I's just that I'm doing it at the outer end of the tube rather than the inner end. So it will definitely change my caster.

I think maybe what you're calling the C cups might be what I'm calling the radius arm wedges. I plan to cut those off, rotate the tubes and center section forward and weld new wedges on to rotate my pinion up. And yes, that would screw up my caster something fierce. But if I then cut off the inner C and rotate it back I can correct that.

I'm planning to cut the Cs off rather than pull the tubes out of the axle for a few reasons. From what I've heard, cutting the Cs off is easier than pulling the tubes out of the center section. And I'd much prefer to weld to the Cs than to the center section with its seals and bearings inside. Plus I need to move both the center section and the inner Cs with respect to the wedges. If I cut the Cs off I can position the pinion angle where I want it and then attach the axle in place before setting the caster. If I do it the other way, then I need to set the caster first (by positioning the tubes where I want them and welding the wedges on to keep it there) and only after that can I position the center section and weld it back to the tubes.

Anyway, that's the plan. I know IT will work. I'll find out if I'm able to execute it!

In going through my old 'wheeling videos that I've been posting recently it came up that I've torn both motor mounts and replaced them with home-made "bomb-proof" mounts. Gary asked if I'd share what I did. I had posted this on another bulletin board back in 2017 when I did the first one, so I'll just cut-and-paste it here:

Two years ago I noted that the transfer case levers had jammed up, likely due to a trans or engine mount letting it move. I had looked at the mounts at the time and didn't see any issues, and it was driving fine, so I didn't do anything.

Then this May we finally got it out on the trails again. When climbing hills in low range, fairly frequently the shift levers (transfer case and transmission) would move to the right and the gas pedal would move down (without the engine changing speed, I was using the hand throttle to keep it steady). So now I knew what my problem was: a torn left motor mount.

After getting home I looked at it installed in the Bronco and thought maybe there was a little gap. But when I jacked up the engine to pull the mount out I found that it was in two convenient pieces!

Since the left motor mount is in tension to resist the engine torque multiplied by the trans and transfer case reduction I decided not to go with another stock mount. I looked at some aftermarket mounts that put the rubber (or urethane) in compression, but they were pricey, most said they raised the motor, and I didn't want urethane. I have some leftover spring bushings from my F-250, so I decided to make one myself using that.

I stayed with the stock mount on the right side. That one is in compression when you're going forward, so it should hold up a lot better than the left side, and I'm not looking to stiffen things up, just keep it from tearing again. If the 46 year old right side mount does fail I'll get another stock one.

It's been a busy summer, so I ended up only being able to work on it over lunch, or for brief bits in the evening. I'm not very proud of the end appearance as I rushed some of the fabricating and the welding. But no one sees it anyway, and once some oil leaks on it and it gets coated in dirt it'll look just fine!

Not much in the way of pictures on this project, just one of the finished mount (on the left) and the stock "2-piece" mount on the right.

As it turned out, I did tear the passenger side one a year or so later and ended up making another just like this one rather than going back to stock.

 

[Nothing Special]

In my Home Movies thread Gary asked:

....

So, when do you head to Moab? What changes are you making before then? Not that this is the thread for that, but...

That may not be the thread for this, but this thread is, so...

The plan this winter / spring is a pretty major redo of the front suspension (among other things). The goal that started all of this is getting my radius arm mounts up higher. I lowered them a long time ago to fix my caster problems, but they are now a limiting factor. I high-center on them pretty frequently. But raising the radius arm mounts isn't something I can just do. I don't know if you're familiar with the concept of a snowball in projects like these??? So the way it goes is...

Raise the radius arm mounts to gain clearance.

But that makes the transfer case the lowest point (with no skid plate). I can clock the transfer case higher, but it will hit the frame rail. So...

I need to notch out the frame (and then reinforce it obviously) to make room for the transfer case.

Also my front driveshaft U-joint angle is currently maxed out, so moving the transfer case front output higher means I need to move the other end of the driveshaft higher too. I plan to do that in two ways.

I'm not sure what lift I currently have. I think it's about 3.5", but possibly a bit more. That gives me room for at least 35" tires, maybe 37". But Lesley tells me that I'm not going bigger than 33" tires if I want her to keep coming with me. So I'm planning on putting a shorter lift on it, maybe 1.5" - 2.5". That will hurt my breakover angle a little, but I'll gain closer to 4" - 6" from the radius arm mount change, so it's still a big net gain.

But that won't get my U-joint angle low enough, so the other change planned is to rotate the differential forward to raise the pinion. In addition to improving the U-joint angle in the double Cardan joint at the transfer case that will also let me get the angle in the single Cardan U-joint at the diff closer to zero, which will help with the driveline vibration I now have in 4WD.

However rotating the axle forward will mess up my caster even more than just raising the radius arm mounts will. And remember, I did that to fix a caster problem originally. So the plan now is to cut the inner "C"s off the axle ends and turn them back to fix the camber.

By the way, doing all of that to the front axle begs the question "why not switch to a high pinion diff?" I've thought about that, and while it would be good for U-joint angles, driveshaft clearance and gear strength, "they say" that you need at least a 4" - 6" lift to get a high pinion diff to clear the oil pan. Lesley doesn't want the Bronco to be any higher so that much lift isn't an option, so I'm sticking with the low pinion.

Oh, and putting a skid plate under the transfer case seems like a good idea now too.

(I'm sure you have no experience with scope creep like that!)

I'm finally starting on my "winter" project. See the post I'm replying to for a full description of the plan (and posts below that discussing it further), but the Reader's Digest Condensed version is that I'm planning on raising the radius arm mounts and transfer case and moving stuff on the axle to improve my driveshaft U-joint angles and my caster.

Today really didn't even scratch the surface. All I did was remove the transfer case and transmission. Getting the trans out wasn't really necessary for the plan above, but while I'm in this far I'm also going to do something about the ring gear that the starter won't always engage. And while I said "all I did was...", that was definitely enough work for one day!

[ArdWrknTrk]

I'm finally starting on my "winter" project. See the post I'm replying to for a full description of the plan (and posts below that discussing it further), but the Reader's Digest Condensed version is that I'm planning on raising the radius arm mounts and transfer case and moving stuff on the axle to improve my driveshaft U-joint angles and my caster.

Today really didn't even scratch the surface. All I did was remove the transfer case and transmission. Getting the trans out wasn't really necessary for the plan above, but while I'm in this far I'm also going to do something about the ring gear that the starter won't always engage. And while I said "all I did was...", that was definitely enough work for one day!

So, Rockwell's and portal axles????

Got it!

[Gary Lewis]

I'm finally starting on my "winter" project. See the post I'm replying to for a full description of the plan (and posts below that discussing it further), but the Reader's Digest Condensed version is that I'm planning on raising the radius arm mounts and transfer case and moving stuff on the axle to improve my driveshaft U-joint angles and my caster.

Today really didn't even scratch the surface. All I did was remove the transfer case and transmission. Getting the trans out wasn't really necessary for the plan above, but while I'm in this far I'm also going to do something about the ring gear that the starter won't always engage. And while I said "all I did was...", that was definitely enough work for one day!

Better late than never. And replacing the flywheel, if that’s the issue, is best done now as well.

Anxious to see how you do all of this.

[Nothing Special]

.... Anxious to see how you do all of this.

I am too!!!

 

[Gary Lewis]

.... Anxious to see how you do all of this.

I am too!!!

It will be well thought out and executed, I'm sure.

[Nothing Special]

It will be well thought out and executed, I'm sure.

A little more progress today. I got the starter, bellhousing, clutch and flywheel removed. That was about all I could take in the cold temps we're having right now (high of about 30 today). It's just too hard to keep your hands warm working on a truck in those temps.

Anyway, I was hoping to see that the ring gear had one chewed up place and I could try to remove it and put it back on clocked a little different to get good teeth in all of the locations where the engine stops. But there are a lot of chewed up teeth (for whatever reason the starter actually looks pretty good).

But that brings up a question. Why is my ring gear all chewed up? The flywheel was new about 40,000 miles (and 13 years) ago. I don't know how old the starter is, but as I said, it doesn't look too bad, so unless an earlier starter damaged the ring gear it doesn't seem like the starter is at fault.

It makes me wonder if I have the right starter? I bought a starter for a '71 Bronco with a 302 and a manual trans, but maybe that's not what I need? This engine is a replacement, and I know it's a newer model year, because the stock flywheel vibrated, so I had to go to a flywheel for a newer 302 with a different balance. Maybe that should take a different starter, even though I'm still using a Bronco bellhousing?

For that matter, the bellhousing isn't stock either. I lost my original one when I had the AOD with manual valve body in it, and got a "new" bellhousing off a Bronco in a junk yard. I don't remember what year that Bronco was. I know it had a V8, and I'm pretty sure it was a 302. So it should be the same as the bellhousing I started with, but I'm not 100% sure on that either.

Does anyone know if there were different ring gears and/or starters when Ford switched the balance on the 302 V-8?

 

[Nothing Special]

A little more progress today. I got the starter, bellhousing, clutch and flywheel removed. That was about all I could take in the cold temps we're having right now (high of about 30 today). It's just too hard to keep your hands warm working on a truck in those temps.

Anyway, I was hoping to see that the ring gear had one chewed up place and I could try to remove it and put it back on clocked a little different to get good teeth in all of the locations where the engine stops. But there are a lot of chewed up teeth (for whatever reason the starter actually looks pretty good).

But that brings up a question. Why is my ring gear all chewed up? The flywheel was new about 40,000 miles (and 13 years) ago. I don't know how old the starter is, but as I said, it doesn't look too bad, so unless an earlier starter damaged the ring gear it doesn't seem like the starter is at fault.

It makes me wonder if I have the right starter? I bought a starter for a '71 Bronco with a 302 and a manual trans, but maybe that's not what I need? This engine is a replacement, and I know it's a newer model year, because the stock flywheel vibrated, so I had to go to a flywheel for a newer 302 with a different balance. Maybe that should take a different starter, even though I'm still using a Bronco bellhousing?

For that matter, the bellhousing isn't stock either. I lost my original one when I had the AOD with manual valve body in it, and got a "new" bellhousing off a Bronco in a junk yard. I don't remember what year that Bronco was. I know it had a V8, and I'm pretty sure it was a 302. So it should be the same as the bellhousing I started with, but I'm not 100% sure on that either.

Does anyone know if there were different ring gears and/or starters when Ford switched the balance on the 302 V-8?

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.