Pinto Car Club of America

Shiny is Good! => Your Project => Topic started by: dave1987 on May 03, 2011, 10:01:17 PM

Title: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 03, 2011, 10:01:17 PM
My 73 station wagon (Brownie) is having it's transmission rebuilt by yours truly! :)

This is the third time Brownie has had it's transmission dropped, second time having it replaced/rebuilt. The C4 I just removed from the car was one that I got from a local PCCA member, as a donation. It was supposedly rebuilt less than 3k miles ago and ran great, but it has been acting up ever since I put it in. Flaring from 2nd to 3rd, which was better with the TransGo kit I installed, and then I lost reverse last week (which came back after driving it to my parents house), and now it doesn't like to grab 3rd gear at all!

I dropped the transmission today and pulled the torque converter. I have taken the torque converter over to the local hot rod transmission place (Idaho Transmission Warehouse), and they are sending it out to be cut open, cleaned out and bad parts replaced. I should have it back early next week, if not by Friday. They quoted me $48.00 for this which is better than the $125 for a new or reman unit.

I was considering just dumping a can of acetone into the converter and sloshing it around to get all of the metal flakes and crud out of it, but I figured that if I am spending $100 on the rebuild kit, $23 on the new cooler and then going to have the other cooler line reformed, I might as well do it all correctly this time! I think the crud filled converter killed the donated C4. :(

The Pioneer Super Master Rebuild Kit (Pioneer part # 753007) arrived today as well, which has a new intermediate band, clutches and steels, gaskets (including valve body), o-rings and front and rear seals.

Yesterday the Haynes C3, C4, C5 Techbook Shop Manual arrived, so I have a great reference with me at all times for clearances, torque specs and endplay specs to ensure this is done right and will last another 90k miles!

I pulled a transmission cooler from an 88 Bronco. It is an aluminum unit with a tube that runs through it with an 180 degree bend in the tube at one end and the two ports for it on the other. It's about three inches wide, 12 inches long and 1.5 inches thick with a lot of fins. I think it will cool the transmission better than the built in radiator one did, and it will be a lot easier to pull and clean later! It was $13.00 from the junk yard and another $10.00 to clean and 125 PSI pressure test it. For connecting it to the transmission, I will be using rubber lines from the steel transmission lines to the cooler, which is 400 PSI rated transmission cooling line. Six feet of this hose was $27.00, but well worth it. Eventually I will be replacing the hose with steel line all the way, but this is more than adaquet for now. I will have pictures of the mounting and installation of this cooler when that time comes.

This will take a few weeks to complete. I only have two days off a week and work all day when it do work. I don't have a lot of money to do this, so I have to wait two and a half more weeks before I can reinstall the transmission and test it, as I will not be using Walmart type F fluid, I will be using Valvoline MaxLife type F fluid which is $5.99 a quart vs. the $2.59 a quart Walmart stuff. I don't want this to be a crappy rebuild process, since I am dumping nearly $250 into this, and I want this to be the last time for a long time thing.
Title: Re: 1973 C4 rebuild and upgrade
Post by: tinkerman73 on May 04, 2011, 07:32:07 PM
I will be watching this diligently! Thanks.
Title: Re: 1973 C4 rebuild and upgrade
Post by: flash041 on May 04, 2011, 07:47:38 PM
I did my c4 this January.Its working perfectly! I had no metal fillings of any kind.The biggest problem was the outer seal on the forward clutch pack was split. It was really easy to do.Just study a lot before taking it apart, take your time, and it will be a piece of cake.
Title: Re: 1973 C4 rebuild and upgrade
Post by: tinkerman73 on May 04, 2011, 08:02:04 PM
By the way, one thing I will say, when I get ready for any kind of rebuild on my car, I will be doing a step by step photo shoot as I tear down. That way I will have reference every step of the way putting back together! LOL.
Title: Re: 1973 C4 rebuild and upgrade
Post by: flash041 on May 04, 2011, 08:44:28 PM
Although i rebuilt mine stock , here are some lik=nks that helped me.

http://www.mustangandfords.com/techarticles/drivetrain/mufp_0605_small_block_ford_performance_transmission/index.html (http://www.mustangandfords.com/techarticles/drivetrain/mufp_0605_small_block_ford_performance_transmission/index.html)



http://www.customclassictrucks.com/techarticles/0508cct_1970_ford_bronco_c4_transmission_rebuild/index.html (http://www.customclassictrucks.com/techarticles/0508cct_1970_ford_bronco_c4_transmission_rebuild/index.html)
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 04, 2011, 11:55:46 PM
flash041, Your transmission rebuild was a major motivator for me doing mine!

I've been researching a lot about the C4 since about august of last year, a couple months before I dropped the original transmission and put this rebuilt one in. Apparently I didn't do enough research as I didn't realize that the metal flakes would deposit themselves in the torque converter or the oil cooler and then be recirculated through the rebuilt transmission upon the first start. :(

I've been doing research since then preparing myself for when I had the funds available to rebuild the original transmission and do everything again, but this time I will be doing things right with completely clean parts including the transmission, cooler and lines, and even upgrading the cooler to something slightly larger and easier to remove when it's time to flush the transmission in the future.

I hope I get it right! But then again, that's why I bought the tech book! :)



Jody, I will be taking pictures as I go. The original transmission, which I am rebuilding, had issues grabbing third gear since I obtained the car. I would just live with it and wait until it warmed up to get a 3rd gear. Then the intermediate servo sprung a leak spraying ATF onto the exhaust pipe and leaving a huge cloud of smoke while driving. I tightened down the servo cover and replaced a missing bolt and that settled down, but still leaked a little bit. Eventually I lost all of my forward gears and it took 30-45 minutes to get the car to grab a forward gear when started cold.

So, pulling apart the original transmission which has officially been deemed DEAD, should be interesting. I'm curious about what I will find as far as worn parts go. Perhaps the metal flakes I found didn't even come from the transmission, but I know they are in it. I'm wondering how much of the friction material is actually left on the intermediate band and clutches, if they are not worn down to the metal. The car always had reverse, so I'm thinking the reverse band should be good and reusable still.
Title: Re: 1973 C4 rebuild and upgrade
Post by: flash041 on May 05, 2011, 08:03:57 AM
Since my transmission was clean , sludge and filing free I  drained and reused my original torque converter . I would not of done this if I saw any filings.Mabe I should have replaced it , but a few trans guys I know thought it would be fine considering the condition of my trans.My main problem was a split seal in the forward clutch pack.
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 05, 2011, 11:58:46 PM
I pulled apart a good deal of the transmission tonight after work. I got the tail shaft and governer off, as well as the servos, valve body, pump, and front clutch pack removed. I pulled apart the front clutch pack and didn't find anything really surprising, just a lot of glazing on the steels, I can't really tell about the clutches but I am sure they are glazed as well if the steels are. The thick friction plate/flywheel type spacer is in great shape, no glazing there. The drum itself isn't glazed, and the band is brown with a good deal of material left on it, I'm sure it is glazed and unusable though.

Dave, no split seals so far! The only damaged seal I see so far is the low/reverse servo cover seal, which is smashed so much it's more triangular now than round, lol.

I'm guessing that it's just the age of the transmission that made it die, since the clutches still look great, they still have the criss-cross pattern to them, it's just the steels that appear bad so far.

Wife called and said she was home from studying so I called it quits for the day and headed home.

It's fun so far, finding out whats inside and how it all works first hand! :D
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 10, 2011, 10:32:09 PM
So the torque converter came in yesterday (monday) but I worked and had a very important formal meeting with everyone of idaho jack in the box's, so didn't have time to get it.

I picked up the torque converter today, and $67.19 later I got myself a nice rebuilt torque converter, repainted to! They also replaced the pump shaft on the converter, so it's as good as new now!

There is some wear on the TC pump shaft which may cause some issues later, so I will be pulling out the new pump and gears that I purchased last year, from Transtar Industries, to avoid problems down the road (literally). That pump and gear set was probably one of the best $20 I've ever spent on this project, unknowingly.

Here are some pictures, very pretty! :)
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 10, 2011, 10:34:13 PM
Here are two pictures of Brownie and the transmission work so far (not to far into the tear down yet, haven't had the time). The mattress boxes on top of the roof rack were in the way in the garage, so on top of the car was the best place to put them! :P


Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 11, 2011, 03:57:15 PM
This morning I finished disassembling the transmission, cleaning every part as they were removed, with gasoline. Before installing each part, however, I will be re-cleaning every part with carb cleaner and drying them with compressed air to eliminate foreign contaminants and/or substances.

I made a mistake earlier saying I had disassembled the forward clutch pack, it was actually the forward/reverse clutch pack. The actual forward clutch pack (second one removed) has no waffle pattern left on the clutch discs, and the steel plates are badly burned. As Dave stated earlier about his sealing rings, mine were dry and brittle as well. They were, luckily, no so hardened that I could not remove them though. I used a jewelers flat blade screwdriver to cut through the ring and then separated the ring from the hub and the hydraulic piston.

I was able to remove everything from the transmission casing minus the outer race for the sprag assembly at the rear of the case. The bolts from the outside of the casing were zoop in position and I ended up rounding out the head of one of them. So I gave up and put the two bolts I WAS able to remove, back.

Before heading home for the day I stopped by Transtar Industries and picked up the new thrust washer kit I had on hold, as well as a new shift shaft seal. Then I dropped off the transmission casing and tail housing at Aamco to have them hot tanked and all cleaned up.

Next week when I reassemble this beast, it will be nice and clean without any trace of metal flakes, shavings, dirt or grease! :D


EDIT: After some extensive calling around, I found the selective sized pump thrust washers at Idaho Transmission Warehouse (same place I got the torque converter from). I will be picking up one of each size on Friday as well as picking up the transmission casing from Aamco. Good day indeed! :)
Title: Re: 1973 C4 rebuild and upgrade
Post by: flash041 on May 11, 2011, 07:15:15 PM
I too left the outer race in.The bolts are in really tight and the bolts have areally small head. Keep it up!!
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 11, 2011, 10:36:55 PM
Good to know I didn't do something out of the "norm" there. Thanks Dave!

Well I picked up the transmission from Aamco on our way to the park. I got to Aamco right as they left the building. The gentleman who helped me earlier let us in to get the parts and he didn't even want payment for it! He said it was easy to just toss in there and have it cleaned, no worry about payment. Score! Free hot tank cleaning and it's shiny again! :D They did miss the bottom of the front of the transmission, but nothing major. It looks a world better than it did before!

First two pictures of the transmission before I started work on it, second two are of the left and right sides of it.
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 11, 2011, 10:39:08 PM
First picture is of the inside front, second of the inside back.

Third picture of the outside back, second of the outside front (there is still some dirt on the case, but none on the pump mating surface).



Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 11, 2011, 10:42:09 PM
And the tail shaft as well...

First picture is the left side, second picture right side.

Third picture is the inside, fourth picture is the wiped out bushing at the rear of the case that the drive shaft yoke rides on. Yes, the rebuild kit came with a new one! :)


Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 16, 2011, 04:09:09 AM
I got a little bit of reassembly done tonight after work. Wife and kids went to friends house to study and decided to spend the night there since it would be late before she got back anyway, so I ventured off to my parent's to play in the garage. It helped to wear me down from work and to actually sleep while she isn't home (hard to do).


I purchased two cans of Walmart stuff carb/intake cleaner, which wasn't enough. I just continued reassembling until I ran out of cleaner, since I am cleaning everything off with it before putting things together again, I spent about three hours on it today.

Here is what I accomplished:

Cleaned pump and replaced torque converter bushing
Assembled both clutch packs/drums and air checked them
Removed manual shift lever from old transmission and installed in new one
Removed valve body from old transmission and set aside for cleaning
Installed parking prawl and gear
Installed shift lever and parking prawl linkage
Installed both reverse and intermediate servos and covers
Cleaned and reassembled governor
Cleaned and installed governor distributor


Not a whole lot, but a lot of the measuring work is finished. Most of my time was spent cleaning parts with the carb cleaner and lubricating them with lucas. I am taking my time with this project but somewhat trying to get it done fairly quickly, since I still have to swap out the rear axle, reinstall the transmission, replace the choke and figure out some electrical issues with the right headlight and radio. I am pushing to get this all finished by the middle of July to take it to Emmett for the big car show here. I don't want my wife to worry while driving it out there.

Tuesday (technically tomorrow), I will try to get more done, if not all of it. I still need to pick up the selective thrust washers for behind the stator/pump assembly, so I can't finish the rebuild until that is done.


And now pictures!
1 - Converter bushings. Old on bottom, new on top
2 - Converter bushing installed
3 - Bottom of pump/stator assembly
4 - Top of pump/stator assembly
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 16, 2011, 04:14:31 AM
Just a couple more pictures. Stay tuned for more updates!

5 - Governor assembly
6 - Forward/Reverse clutch pack/hub assembled
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 18, 2011, 12:47:17 AM
I finished rebuilding the transmission today! :D

Just as you have heard from other people and read about online, it is very easy to do, just take your time and follow a manual while doing the job and you can't really go wrong!

One thing I did want to point out to everyone is that there are two thimble/basket filters in the C4. One tiny one for the governor distributor, and another one for the valve body feed port. Figuring out which of the two ports is the feed port for the valve body can be easy to mix up. Just remember that it is the larger round hole closest to the manual shift lever. (Picture below)

I replaced all of the thrust washers in the unit with new ones that I purchased in a "thrust washer kit" from Transtar Industries. I also replaced the #1 thrust washer with a thicker selective washer. The #1 washer is made of plastic and is directly behind the pump. I purchased one of each size minus the largest (there are five sizes) for $1.59 each and $2.24 for the second to the thickest. I will keep them around for when I rebuild the other C4 that Carl gave to me before I give it away.

The only thrust washer I could not locate to replace is the selective #2 thrust washer which goes behind the stator support. No one in town carried them and I could only get one size of the #2 washer from Transtar Industries if they were to order one from Salt Lake City, so I reused the original one.

I took disassembled the valve body as well. I already installed a TransGo shift kit in this valve body before I started this work, but I used it in the other transmission which had contaminated fluid, so taking it apart and cleaning it was a MUST. While I had it apart, I replaced the check balls with new ones (again), and reinstalled the "hockey puck" on the upper half of the valve body, to soften the shifts a little, since my wife will be driving this to Emmett this summer.

I replaced the drive-shaft bushing on the tail shaft housing, installed magnets in the pan to collect any potential/future debris, and mounted the bell housing.

The cooler fittings are loosely installed at the moment because I forgot to bring my modified 5/8" open end wrench with me. The collar nut on the 90 degree brass fittings are extremely hard to remove or tighten without a very thin open end wrench. So I went to the pawn shop last year, when I was doing work on the other transmission, and bought an extra 5/8" wrench to take to the grinding bench. Pictures of it below.

Now pictures:

1 - Proper location for thimble/basket filter for valve body
2 - Bottom of valve body
3 - Top of valve body
4 - Valve body installed
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 18, 2011, 12:50:21 AM
5 - Tail shaft end with new oil seal
6 - Two magnets in pan to collect metallic debris
7 - Modified 5/8" wrench (top)
8 - Modified 5/8" wrench (side)
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 18, 2011, 01:00:42 AM
When those of you who have never worked on an automatic transmission before (like myself before I did this project), the thought of it may be intimidating. Great news though, the Ford C4 is an extremely simple beast, and there really are not many parts. The hardest part is remembering where parts go and keeping them in order, so organization and a clean work bench is a MUST. Having a manual with you while doing the work eliminates the guess work, especially with the Haynes C3, C4, C5 Tech Book. I found the illustrations quite helpful at times when I was unsure of something!

I did not install the torque converter on the transmission yet, as I don't want it to sit out for another week or two just collecting dust. I will wait until I am ready to install the unit and then install it.

Also, I plan to dump the rest of the lucas oil treatment, that is left over from the rebuild, in with the type F fluid I am added. I could not find the max life fluid which has the lucas treatment already in it, so adding the rest of this bottle and filling the rest of the transmission with the Valvoline regular type F should keep it going strong for awhile!

When it comes time to install the transmission, I will take shots of the mounting of the new cooler. I also have to pull the second half of the return line and have it re-formed since it appears to have leaked in the past and someone tried to cold weld it. Once the transmission is installed, I will be changing out the rear axle and the drive-line work on Brownie will be complete!

Photo 1 - This really shows best, everything I worked on, in a consolidated shot.

Photo 2 - Right side of the transmission. Clean and rebuilt! :D

Photo 3 - Left side of the transmission. Again, clean and rebuilt! :D

Photo 4 - The new cooler I will be using. As stated earlier, this is a Bronco II oil cooler. It is about three times BIGGER than the small ones I have found on Mustang IIs and Pintos with the C3 and C4 transmissions, so I believe it should be more than adequet for a stock 73 Pinto station wagon
Title: Re: 1973 C4 rebuild and upgrade
Post by: pintoman1972 on May 20, 2011, 08:40:00 PM
Which color band push on Vacuum Modulator are you using?
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 21, 2011, 02:59:00 AM
I'm using a yellow band modulator, same as the original. I believe it was $22.00 from O'Reilly Auto Parts but had to be ordered from the Salt Lake City depot because the two they had in the store as "yellow band" modulators were red and green ones.
Title: Re: 1973 C4 rebuild and upgrade
Post by: pintoman1972 on May 21, 2011, 08:33:01 PM
Ok Dave,

I am also using the adjustable yellow band modulator.  Even though the adjustment only changes the shift points a few MPH up or down, the early shift points help with what little gas milage I have.  I don't have the luxury of running lean or changing the timing for better milage so I find it where I can.

Am enjoying your updates as I am sure many other are also.

Dick
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 21, 2011, 11:42:21 PM
Glad to hear someone is watching the thread! :)

One thing I should mention, is that the rebuild kit that I purchased from Pioneer is a C4/C5 kit, so it comes with a handful of extra seals and two extra oil rings for the stator support. I called Pioneer myself to verify this. So, if you are looking for an early 80s C5 kit, this would be the one!

Monday I will be finalizing this project, including changing out the rear axle for a 28k mile axle I bought off craigslist and used briefly in my 78 Sedan. It's repainted with new seals. When I got Brownie running, the rear axle was the only thing I didn't do any work to, it still has the ancient gear oil in it, which didn't even need topping off. I knew I would change it out, and figured why both messing with it?

There will be pictures either monday night or wednesday night at the latest of the new oil cooler install as well, so stay tuned!
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 24, 2011, 02:51:02 AM
It's finished! Finished and I drove Brownie home tonight! She drives like a dream now! :D

After 15 hours of work I installed the transmission and upgraded the cooler, as well as swapped out the rear axle! All is well in dave1987's Pinto Land! :D :P



So I scrapped the idea of using the Bronco II cooler, as the A/C (non operable) condenser was in the way and the Bronco II cooler wouldn't get any air flow. I didn't want to remove the condenser from the car, so I had a better idea. Why not just use the condenser as an oil cooler?

So I did! I had the condenser cleaned and pressure tested and it came out just fine. Next I got the two piece cooler feed line modified. The front half of the line was very poorly repaired at some point in time, so I was originally planning to just have it reformed, but the size of the fitting on the condenser required a 1/2" line to be used. My local brass and steel supplier was able to come up with a series of brass fittings to step the 5/16" original (rear half) feed line up to 1/2" (front half) line. They then gave me a 20" section of 1/2" line which was coupled to the 5/16" line with adapters to step up.

I am using the upper port on the condenser as feed  with the 1/2" fitting and the lower port as return with the 5/16" fitting. Everything is working great!

I'll have pictures up by wednesday night.
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 24, 2011, 08:28:57 PM
For the condenser, I pulled it and took it and the tubes to Andy's Supply to figure out a way to connect the cooling lines to it, and while they were making the lines I dropped off the condenser at Radiator King to have them flush and pressure test it (which came out positive). For all of the fittings and adapters it cost me $25, including the section of the 1/2" steel line. The cleaning and testing of the condenser cost me $15.00. That's $40 more on the project, but it keeps the outward appearance original. The only difference you might see is the missing hoses from the A/C compressor, which doesn't even have a belt on it's pulley right now.


1 - Condenser (nearly three times the overall surface than the Bronco II oil cooler

2 - Return line for the transmission on the condenser/cooler. This originally connected to the expansion tube, and connects to the lower condenser port.

3 - Return line for the transmission on the condenser/cooler. This one originally went to the A/C pump and was part of the hose.

4 - This shows where the tube was cut from the compressor hose.
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 24, 2011, 08:34:43 PM
5 - The return and feed steel lines on the condenser and connected to corosponding hoses, which then connect to the steel lines to the transmission.

6 - Condenser mounted with the hood bracket in front of it and the grill reattached.

7 - This is the original front half of the feed line. The brass something or other repair in the middle of the line worried me and is why I planned to have it re-formed.

8 - The two lines would connect as shown. The transmission half (rear half) of the line is on the left, and the front half on the right. I'm not sure if it is like this from the factory or not though.
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 24, 2011, 08:41:21 PM
9 - This is the series of adapters and compression fittings connected

10 - And this shows an exploded view of them all as follows (left to right). 1/2" compression nut, sleeve, 1/2" to 5/16" adapter, 5/16" male to female adapter, sleeve, 5 1/6" compression nut.

11 - This is the rear half of the feed line with the 5/16" end of hardware on it (line connected to the transmission)

12 - This is the new 1/2" line for the front half of the feed line. I had to bend it straight because the bend was at the middle of the motor oil pan, but 1/2" isn't hard to bend without kinks. The line has the 1/2" end of hardware on it.
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 24, 2011, 08:44:48 PM
13 - I thought I would post this to show proper depth of the torque converter before mounting it to the motor. This is how deep the TC should be in the 2.0 bell housing after it has slid over both sets of splines (the stator and the input shaft).

14 - One more shot of proper TC depth.
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 24, 2011, 08:50:16 PM
And that's it! All finished up. $314.11 in total parts and work performed, the rest was my own labor. Not bad at all. It shifts smoothly, downshifts to passing gear smoothly, engages smoothly and every time, even has given the car more acceleration!

I think I got it right this time, no more transmission work for awhile!

The only thing I noticed was a small transmission fluid drip from the passenger side, I'm guessing it's the feed line's 90 degree fitting. I need to look at that tomorrow and stop the leak before it gets bad.

Only piece of advise I can think of to give now, is...If you plan to do your own transmission, pay to get decent parts (if stock, a Pioneer kit will work, and if performance go with a racing kit), take your time (it's easy to get overwhelmed),  and don't cut corners. While my upgraded cooler probably isn't 100% necessary, but the peace of mind from knowing it will not overheat again is well worth the time it took to make everything work together.
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on May 28, 2011, 01:35:40 AM
I fixed the leak today! It was the rear (return line) 90 degree fitting. I forgot to put an o-ring inside the female side where the line screws in. For extra precaution I wrapped some high density industrial grade thread tape around the threads of both the line nut threads and the male fitting threads to stop any leaks. All sealed up now and working well!

Now I'm afraid that the condenser might have been a step to far in this project, as it may be blocking flow some due to it's small internal passages. I may be swapping out the condenser for a F-250 oil cooler in the near future, we will see. I need to call around to some tranny shops and get their advise on the topic.
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on June 26, 2011, 11:19:45 PM
So I noticed a leak today.....

The output shaft seal at the end of the tail shaft seems to be leaking, as I have fluid all over the tunnel under the car!

I have a new seal, and new bushing, why is this happening? Is there a such thing as a drive shaft repair sleeve that I could use to remedy this?
Title: Re: 1973 C4 rebuild and upgrade
Post by: RSM on June 26, 2011, 11:54:10 PM
Hows the balance on the driveline? Any vibrations?
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on June 27, 2011, 12:26:50 AM
There is a vibration while going from 35-40. Think the drive shaft needs balanced?
Title: Re: 1973 C4 rebuild and upgrade
Post by: Srt on June 27, 2011, 02:28:47 AM
i am reading it too! & i think you've taken a lot of the mystery out of the task of working on & maintaining automatic transmissions
Title: Re: 1973 C4 rebuild and upgrade
Post by: RSM on June 27, 2011, 11:13:17 AM
I would pull the driveline and have it checked and install a new seal and bushing just to save more headaches down the road. The yoke could also be an issue and a driveline shop can check it out for you. The vibration could also be tires. How old are they and when were they balanced last??
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on June 27, 2011, 12:18:29 PM
Well then it sounds like its time to check that driveshaft. The tires are new as of the 20th. Balanced and all!
Title: Re: 1973 C4 rebuild and upgrade
Post by: FCANON on June 27, 2011, 12:28:03 PM
I've had new U-joints that were crappy... Just say-n!

FrankBoss

Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on June 27, 2011, 01:06:14 PM
I was wondering about the U-Joints, myself, not entirely sure that was the case though.

I have rebuilt the transmission, swapped out the rear axle for one that is known to be vibration free (was in my 78 sedan, originally came from a 73 wagon as well though), new U-Joints, new transmission and motor mounts, and new tires with freshly balanced rims.

The only thing I have not have professionally tested yet, is the drive shaft. If that's not it, I don't know....

I have a shop who will spin balance my drive shaft for $70.00. Isn't that a bit expensive though?
Title: Re: 1973 C4 rebuild and upgrade
Post by: RSM on June 27, 2011, 03:04:23 PM
I had a driveline built for my drag car when I installed the 9" I can't remember what the cost was but $70 might be in the ballpark for a balance. Just make sure and have them check the yoke real good...might be worn where the seal runs on it.
Title: Re: 1973 C4 rebuild and upgrade
Post by: NJford on August 16, 2011, 11:47:55 PM
  If seal still leaks check the slip yoke make sure its not worn and also check the spring on the seal  are know to pop off when installing seal. One trick to void come backs is to pack seal with petroleum jelly and put into freezer for 20mins then install.Also you can tighten the spring alittle if your slip yoke is worn by turning spring apart and cut 4 coils off the female end and turn male end back in and reinstall. I hope this helps you.
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on August 17, 2011, 01:38:13 AM
Thanks for the great input NJford! I never would have thought to tighten the spring any! I will be replacing the tail shaft bushing one more time just to be sure that isn't a culprit in all of this. Also will be doing the spring tightening with the seal and installing it with the petro gel and freezing it. Actually I might as well do that while I have the tail shaft off so I can tell for sure if the spring comes off or not.

Again, thank you. I have been researching this problem for weeks and never found anything this useful. Glad to have you on board with the Pinto community! This is what we're all about! :D
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on January 26, 2012, 06:34:13 PM
So for the past two months I have been working off and on rebuilding the transmission that Walt gave me but failed shortly after. I believe I found the culprit to it all as well. It seems there there was negative end play and everything was mashed together. It is surprising it lasted as long as it did! When I pulled apart the clutch packs there was absolutely NO lining left on the clutches for the direct drum, but the rear drum seemed to be just fine.

Also, the LEAST noticeable damage was the sun shell. It seems that the negative end play forced the end of the sun shell inwards, making the end of it concave instead of flat. I spent an hour an a half trying to figure out why I couldn't get the sun shell tabs to lock into the direct drum tabs.

I managed to locate a good sun shell locally and here is the difference pictures:

Pic 1) You can see the bowl type warping in the old shell's base in this picture

Pic 2) You can see where the forward planetary gear set was actually making contact with the inside of the sun shell. That's a lot of force required to bend the shell in that much!

pic 3) Here you can see how much the sun shell's bushing wear plate was bent due to the negative end play.

pic 4) And here is the difference in the plates when removed from the sun shells.
Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on January 26, 2012, 06:44:44 PM
Pic 5) Now you can see the most notable difference between the good and the bad shells.

Pic 6) Until I get back to the garage next week to reassemble everything, I wrap the parts in plastic wrap to keep them clean, an to keep any oils or fluids from making a mess at home! (this is how I store parts in storage as well)

Pic 7) For reference, these are the valves assemblies that get sticky from dirty fluid, or the valves themselves start to wear after time. When rebuilding your transmission, be sure to remove the valves and clean the valve body and governor well. Sediment and fluid turns to a paste like substance and gums itself into places it shouldn't be. To polish the valves I use Mother's Aluminum and Mag polish on a microfiber towel, then stick the spring end of the valve into a cordless drill chuck and wrap it with the polishing towel. If no spring end is available, I just polish them by hand the best that is possible. It works very well and gives amazing results!
Title: Re: 1973 C4 rebuild and upgrade
Post by: johnbigman2011 on January 27, 2012, 01:31:17 AM
Dave, I'm impressed. I know you must of mentioned it somewhere in all the detailed instructions that you provided. How do you change the shift seal? My C4 is leaking around the shift linkage going inti the side of the trans.

Title: Re: 1973 C4 rebuild and upgrade
Post by: dave1987 on January 27, 2012, 03:04:46 AM
First off get a pan gasket and filter kit, miht as well change the filter while you have the pan down.

You will need to drop the pan at the rear and let the fluid drain out into and oil pan, discard that fluid. When its done dripping, remove the large head bolts to drop the valve body, more fluid will drain so keep your pan handy!

Once you have the valve body out you need a 3/4 inch open end wrench to take the shift shaft bolt out, be sure you have the neutral safety switch and the linkage removed as well. Once the nut is off you can withdraw the ahift shaft out the side of the transmission.

Pry out the seal from the outside with a flatblade screwdriver. Now two in the new seal flush with the casing.

Assembly is the reverse of the disassembly.

Don't forget to lube the new seal and the shaft with trans fluid before installing the saft again.

Also, you may need to drop the trans mount to let the transmission down enough to withdraw the shift shaft, or it may run into the tunnel.