"NEW" rearend for the Convertible

Update your progress on your various car projects.

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Racin'Jacin
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"NEW" rearend for the Convertible

Post by Racin'Jacin »

Phase 1:

Well it seems every 2 or 3 years the rear wheel cylinders lock up on the old Rambler convertible. Not sure why this particular car is more prone to that than any others (especially since I drive it the most and it sits in a heated garage during the winter) but in any event I am tired of it.

So we've started the recipe with annoyance to which we'll sprinkle in a little cheap bastard and viola we've got the proper ingredients for a fun project.

I started with a brand new set of wheel cylinders. I ordered a piece of stainless DOM tubing. I bored the wheel cylinders in the lathe using a 4 jaw chuck - in hindsight I would make a pair of bushings (a "fixture" of sorts) and use the 3 jaw (lesson learned). Anyways the tubing was pretty good on the OD but not perfect - I left it as made and split the difference meaning that it mic'd .994" one way and .996" the other so I called it .995" - I then bored the wheel cylinder to .996" which should be a very light press since it really isn't round to begin with. I also used some green loctite as some insurance. It pressed together incredibly hard - not sure if the loctite was starting to setup or if it was just a result of the length since it was nearly 3" long. It was hard to do with my little vice, but manageable.

Oh yeah I also pre-bored the tubing - I was shooting for about .005" clearance for the piston, but it measured .004" which I thought was no big deal at the time. After it was pressed together I assumed I would loose about .001" - I was surprised it was much closer to .002" - so that only left me a theoretical clearance of .002" - a bit tight methinks especially since the tubing wasn't perfectly round to begin with. I ended up honing it out to be closer to .004-.005". It would have been easier if my first shot for .005" clearance was actually on the mark - in the end not hitting that made me hone out an additional .001" which don't sound like much, but trust me doing it with a Milwaukee drill and a brake hone is about as thrilling as watching paint dry!

So are any of these numbers right?? Stay tuned we'll find out together! ha ha ha

What did I learn?? Well first off I spent a LOT of time fiddling around - but no complaints there, but it does tell me that the guys who do this professionally are definitely giving you a bargain!!!!

I also learned that using the 4 jaw wasn't the best approach by far. Next time I will definitely go 3 jaw. This way I can bore the w/c. Press in the sleeve. Bore the sleeve in place & then hone. Much easier than what I did!!! Live and learn.


Only thing left to do now is to test it!!! Cross your fingers!!!



Jacin
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Racin'Jacin
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Re: "NEW" rearend for the Convertible

Post by Racin'Jacin »

Phase 2:

Rustoleum rebuild for the spare rear I have. Wait we better back up a bit. The convertible has a vibration on the freeway and for a long time I attributed it to the banged up drive shaft, but upon closer inspection I've determined the input shaft (aka pinion) is BENT! Yes, bent. I've never seen this before and who knows how it happened (it's been this way since I got the car), but all I know for sure is that I am tired of the vibration so it's time to do something about it.

It's pretty tough to see in the pics, but the one hiccup I had with my spare rear end is that the perches were crap - too rusted to use - so out comes the blue wrench and we get rid of those. They were the same size as some tubing I had so I made a replacement set out of that - good as new (hopefully). So NOW we fast forward to the rustoleum rebuild. The rear seems fine - pinion feels good so I figure I'll just toss it in and see how it goes. The down side to that plan is that the original drive shaft IS banged up and could be still a factor in vibrating so Ebay to the rescue - would you believe I find a '64 Rambler American drive shaft for under 30 bucks!!! So I get it and it's pretty nice, not perfect but definitely worth the effort. Also if you notice the shaft coming out of the rear is splined with no retention method. The rear "yoke" on the driveshaft clamps down on that spline with a tapered threaded section - set the position and crank the nut - done. Ahhh not quite that simple you actually have to pull the rear end back 4 or 5 inches to slide the yoke out of the trans to remove the driveshaft - loosening the nut is not enough room. That's why I am doing everything at once - what a goofy design.

I could have opted to rebuild the original rear end (and maybe I eventually will) but for now a simple R&R approach makes the most sense. I'll try to gather all the parts for dirt off Ebay just to have that option open in the future. Hell maybe I'll try to straighten that bent pinion shaft - it's not like I can ruin it - it's already garbage. ;-)


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Fred32v
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Re: "NEW" rearend for the Convertible

Post by Fred32v »

Serious fun finding that drive shaft on ebay. The housing looks ready to go, but
the fancy wheel cylinders from Phase 1 are not in the picture. Still nice work!
Fred32v
GMC Canyon Crew Cab Short Box 4x4 V6!
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MostMint
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Re: "NEW" rearend for the Convertible

Post by MostMint »

Fred32v had a little problem with a bent pinion gear. I can't recall the specifics but I'm pretty sure when you break the front u joint and the drive shaft comes down well let's just say anything can happen.
[quote="Basement Paul"]Is that a mint rocketship on the hood?? :shock:
-BP[/quote]
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Racin'Jacin
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Re: "NEW" rearend for the Convertible

Post by Racin'Jacin »

Fred32v, yeah I can't begin to tell you how shocked I was to find it. The problem with them is that goofy threaded coupling - I can't imagine you could find those new anywhere so running over to a driveshaft place and having a new one made doesn't work easily for this car, but now that I have a spare - no worries!

Yesterday proved to be a bit of a distraction - I was thinking maybe I'd get some more done on the rear end swap, but I was easily lead astray. I only had a little time available so when I finally got out there I needed to pick a small project to work on (ok well that's an excuse, but it works so I'm going with it). Anyways I have wanted to add some writing on my fuel lever for the dragster (instead of the black sharpie writing that always wears off) so I finally chucked it up and made some itty bitty chips. I now know why guys have this done on a CNC - it's a slight pain in the ass to do on a manual bridgeport!!!


Image


Now I just need to decide if I should fill it in with red paint like I did on the KILL switch.


Hmnnn decision decisions....

I opted to paint it - I think it looks better.
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Racin'Jacin
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Re: "NEW" rearend for the Convertible

Post by Racin'Jacin »

Phase 3:

Time to stop foolin' around and get back to bizness!

At noon I told "D" (my ten year old son) that I needed his help for a BIG JOB in the garage today. We wrapped it up just after 6:00!

Swapped the rear end - plus that goofy driveshaft - hooked everything back up & included a brake bleed. That last part would have gone faster had I been able to find my flaring tool kit faster - grrrrr!


Did a quickie test run on the jack stands & everything looked fine. I couldn't apply the proper torque on the rear end nut so a test drive was out of the question. I will have to hit up my buddy Stan and see if I can borrow a GIGANTUAN wrench (my biggest was 1-3/8' and it looked about a 5/8" too small!


Soon as I get a wrench - We'll be ready for a road test - we'll see if mother nature cooperates - no biggie if we don't get in though - there's always the coming spring!!!!!


I can't state how elated I was that my son not only helped but never complained was always attentive and most importantly right there with me every step of the way!!!! A real trooper!!! Good Times for sure!!!!
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Fred32v
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Re: "NEW" rearend for the Convertible

Post by Fred32v »

As I see it, the best part of that install was having your son there and interested. :D
Fred32v
GMC Canyon Crew Cab Short Box 4x4 V6!
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Racin'Jacin
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Re: "NEW" rearend for the Convertible

Post by Racin'Jacin »

Fred32v, I couldn't agree more!

Here's a pic of the rear installed - looks a tad out of place with it painted and everything else not, but so be it.

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Here's a shot with the indicator on the "bad" pinion

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You can see there's about .058" runout - I'm not an expert but I would expect this to be .002" or .003" - I wonder if the manual has any specs for this. I probably wouldn't panic even up to .010" but I'm nearly a 1/16" of an inch!! That's a country mile in my book!


I'll see if I can't measure the good one later today - just for kicks.
Anyways - I made another goof - I should have pulled the driveshaft OFF the bad rear end while it was still in the car, but I suppose it's a mute point - I didn't have that wrench anyhow so I'll wrestle with it out of the car when I finally borrow one.


Can't wait to test drive it!!!!!
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Racin'Jacin
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Re: "NEW" rearend for the Convertible

Post by Racin'Jacin »

Phase 4: (Put a fork in it - I think it's done!)

Well I wire brushed the "new" part so I could put the dial indicator on it. I was measuring LESS than .001" - Now THAT'S what I'd expect (actually better than I expected) I figured the rust would add some inconsistency.


So the final step was to torque the nut on the coupling! I tripped over some big "junk" wrenches someone gave me long ago - the bigger one looked like it had a grinder taken to it to "open it up a little" so that was a perfect candidate.

I chucked it in the Bridgeport and threw a High Speed end mill at it - to which the wrench wholeheartedly laughed at. So I dug through my bits and pieces and found a carbide endmill - ahh much better!!!



Image

So now that I can actually tighten the nut I went as far as I could by hand and then stuck a floor jack on it to give it a final crank or two. The manual listed some ridiculous figure (300 foot pounds! ) which is awfully hard while laying on your back with a 12" long wrench - so the hillbilly method will have to do for now. I suppose I could always put a force gauge on it and ..... who am I kidding? This thing ain't going no where!!!


Image

Took about 10 minutes to resize the "junk" wrench

and about the same to "torque" it.

Only thing left to do now is wait for warm weather!!!!! ...or where's my parka???
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Racin'Jacin
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Re: "NEW" rearend for the Convertible

Post by Racin'Jacin »

Well patience isn't necessarily my strongest point so waiting for warm weather proved futile.
Instead I fired it up and took it for a short cruise on the freeway! Lotta fun, but I should have brought my gloves!

The good news was the vibration is gone ! yea! The bad news is I couldn't talk my son into going with me! no sense of adventure.... yet :-)
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MostMint
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Re: "NEW" rearend for the Convertible

Post by MostMint »

So I take it the car is not really a convertible at the moment or you could put the top up!

Glad to hear it's back on line.
[quote="Basement Paul"]Is that a mint rocketship on the hood?? :shock:
-BP[/quote]
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Racin'Jacin
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Re: "NEW" rearend for the Convertible

Post by Racin'Jacin »

Top D-O-W-N !

Good times!
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GMJohnny
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Re: "NEW" rearend for the Convertible

Post by GMJohnny »

I love the fact that you're cruising around with the top
down in December. Being a convertible lover, I have a certain
temperature that defines when the top goes down. 55 and up
means the top is down!! I also have some rules of thumb that I
follow. 1) In town, windows down!!! 2) Top down, visors up!!
3) Run the heat if needed, but NEVER let on that you're cold, because
when the top is down, you're always "cool."

GM
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