coppercutlass

Ok guys Just a little update . I got all of the piston assembly's put together. Progress halted as my friend has my torque wrench and I need to torque the pump bolts. Tommorow I will hit it again and check the piston assemblies with air .

coppercutlass

Ok guys so today I checked the intermediate clutch . It moved good and held air. The book states to use 25 to 30 psi and considering I had a makeshift nipple to pressurerize the assembly I heard hissing But i regulated it on the air gun it pumped up and I saw no bubbling of trans fluid on the edges which would indicate an air leak on the piston assembly I would assume. Any input on this guys. With steady air and positioning the air nipple just right all I heard was the hissing of the air going in nothing external. Im going to buy rubber adapters for my blow gun and double check it but it did do it's job when I checked it. I had to do like a 3/4 to half trigger pull on the blow gun because my compressor would not work under 40 psi on the gauge so im going to use the regulator from my paint gun to regulate the air going into the air gun at a steady 30 psi. I found out old valves ( the stem ) fit perfect to align the pump body they fit nice and tight.

oldstata

Are you going to be installing this soon ?

coppercutlass

Not any time soon. I just checked that clutch since I just assembled the pump again.

coppercutlass

@ matt69olds the direct clutch piston is the one I mainly want holding 5 clutches correct ? Or should I do all of them. I'm sorry for all the questions but I want to do this to where I get the best bang for the buck. I also have a question regarding the cushion spring it say's to leave it out and check the clearance and if not I need a diffrent selctive plate. Do I just use a regular steel in it's place ? Or do I get a diffrent plate to get the right clearance. I haven't assembled anything just the intermideate clutch piston. I want to make sure I understand some of the mods.

matt69olds

Ideally you want 5 clutches in both drums. The forward drum (the one with the input shaft) is applied anytime the trans is in a forward gear. The direct drum really needs 5 clutches, it is asked to apply and hold going into 3rd gear. As for the clearances, you can adjust clutch clearance with different thickness snap rings, backing plates, piston thickness or steel plates. The rule of thumb is .010 to .015 inch clearance per clutch plate. The cushion spring (the wave plate) needs to left in place for the intermediate clutch, it helps absorb shock load and keeps the sprag alive. You can eliminate the wave plate in the direct clutch, there is no sprag to damage and wont hurt anything.

If you want you can scrape the friction material from a old low/reverse clutch disc, cut it in one spot and spread it over the pump in the cavity where the intermediate piston would sit in the pump. Doing this tightens up the clearance in the 2nd clutch packs and help with the apply and release speeds.

coppercutlass

@ matt69olds Ok so today i re air checked the intermediate clutch and it worked great with my makeshift tool. Then i checked the direct clutch and it moved good but i did hear some air escape bt not from the seals. I did a little reading and read that it escapes from the stator it's common but with 30 psi of air held it pmped up and stayed up . I also started dry stacking my clutches to figure out my clearances . With 2 steels on the bottom i got .045 so with 3 clutch packs that .015 a piece. Is this correct. Also is it okay to use 2 steels to attain the clearance. Im going to machine the pistons this weekend but im playing with installing the clutches jst to see what i can achieve. Again i really apreciate the help matt69olds . Also if I do the 5 clutch packs my clearance would go to between .050 to .075 ?

coppercutlass

Btw here is the tool I made to hold 30 psi of air.

matt69olds

Most builders consider .050-.060 ideal, a little looser is better than too tight. Mix and match steel plates, snap rings, backing plates or machine the piston to get the clearance where you want it. Thats for the direct clutch, the forward clutch really doesn't care how tight the clearance is, as long as everything turns freely when its not apply all is good.

The intermediate clutch always has a lot of clearance, thats why people use a old low/reverse clutch under the piston to act as a shim. It will give the trans a quicker 1-2 upshift and makes a 3-2 downshift firmer.

If your using Teflon rings on the pump support they will show a bunch of leakage. They spread out and seal against the drum once the trans is in service. If the pistons pump up and apply with a solid thud with 30 psi of air you should be fine.

coppercutlass

Cool so I should not double up on the steels on the bottom only to get clearance if needed ? I thought since the bottom of the pack didn't know weather it had the cushion spring or a steel I would be able to get my clearance that way. I did that just messing around. Im cutting the piston on my friends lathe Friday and I will measure and clearance it all out. The other little thing I found weird is when I was applying pressure to the direct clutch I did have to hold my finger at times over one of the opposing holes . I checked the ball check in the piston and it was free. I could not find anything on this. Again I really appreciate the help .

coppercutlass

So today I machine the direct clutch piston. Since both my friend and I have a background in machining we measured run out and set it up to make sure it was a flat as possible. Here is what I did to get the clearance into the cut measurement. I put a stack of 3 clutch packs in and then added a steel to get .045 I aded the .045 and the width of the steel roughyl .115. So my gap with 3 clutch packs was .115 . Then I mesured two clutch packs to find out how much.more we need to get to zero clearance between the diffrences of the two. Then we added .050 and on the first fit we got .053 clearance. Tommorow we do the other piston. It took us about an hour to set the lathe up. Total work time 2 hours but we did it like a machinist would.

coppercutlass

both drums are now machined I have .025 clearance on the forward clutch stack. So tomorrow im cleaning everything up and assembling it all then probably gonna slow down once I hit the valve body.

Professur

Valve body's easy. Just watch that your cleaner doesn't remove the colour from the springs .. that makes things complicated real quick.

matt69olds

If you left the center seal out of the direct drum or left one of the sealing rings off the pump (like is outline in the TH350 build tips) you will need to block the hole that is labeled Reverse in the pump for the piston to apply. That hole either needs blocked with a 3/8 (I think) set screw or will be blocked by the special spacer plate and transfer plate included with the shift kit.

As long as the clearance in the direct clutch is .050-.060 you will be fine. It doesn't matter how you arrive at this clearance, I prefer to omit the waved steel plate. Sounds like you have it figured out.

Refresh my memory, what shift kit did you buy?

coppercutlass

I think the seal trick is if you are not doing a shift kit style deal for the dual feed . I'm using the b&m shift kit that came with the trans kit everything says to not do the seal and plug mod if you are using a shift kit. I left the wave plate out in the direct drum and used the wave plate in the forward drum as the book stated it does not enhance performance on that assembly. I know how you get the clearance does not matter but since getting a different selective plate was not really an option for me we had to make sure our cut was going to be dead nuts. I just thought I would mention how we achieved our clearance based on pre measurements so if anyone was interested in doing the same they had some sort of way to figure it out. Although I found it odd the b&m kit supplies prints for the machining but neglects to explain that they are talking about machining a 4 clutch pack piston. I had a 3 clutch piston on the direct drum and the pre measurements really screwed me up which is why we spent some time to figure it out. I then decided to reference the ron sessions book which references the b&m mod prints., what they specify is different from what is in the supplied b&m instructions dimension wise but same drawings . We might have over thought it but a lot of research said to cut .160 - .170 and we cut much more than that off (.233) which if you cut .170 off a 3 clutch piston you would be wayyyy too tight. maybe we over thought it but the end result was great lol.

matt69olds

Wow, I missed the part about a 3 clutch piston! I cant recall ever seeing one of those. I'm guessing your core had to have been originally behind a 6 cylinder engine.

If your interested, its easy to converter the valve body to a manual/automatic style. Depending on what shift kit was included with the kit it might already have it. Find the low control valve in the lower right corner of the valve body(with the worm tracks up and the accumulator piston in the upper right corner). Remove the valvetrain, omit the spring and block the valve bottomed out in the bore. You can use a copper tube, steel brake line, whatever fits in the bore. This prevents governor oil from overriding the manual valve position.Leave it in drive, it will shift automatically. It will downshift into any gear at any speed, and wont upshift from the gear you have selected. Most valvebody calibrations will prevent downshifting or holding a lower gear after a certain speed. Blocking the valve prevents this

coppercutlass

I belive my kit has the one that has manual control.

coppercutlass

My clutches are soaking, I cleaned up everything and made sure I had no metal fragments left from machining the pistons. Tommorow I start final assembly. Im also ordering up a new tq. converter. Im getting a jegs unit 2300-2700 12 in. converter It's cheap and I ran a jegs unit in the past and it did it's job and worked well. I just hope it stalls closer to the 2500 rpm range which I think my engine will make enough grunt to do so. My cam needs 3000 stall for optimum track performance but a 2500 works good for the cam I have. I wouldn't mind paying 280 for a Midwest converter unit built for my set up but I would hate if my trans failed and I junked up the new expensive converter. 134 is easier to swallow than 280.

coppercutlass

Im happy to say I got all the clutch assemblies together. All that is left is the valve body and tail shaft and odd and ends. I had to re do a few things as I went along but nothing major just clutch pack alignment issues.

Tony72Cutlass'S'

So, what does a "2300" stall converter mean.

Does that mean you can rev the engine to 2300 RPM and the transmission won't engage?

coppercutlass

Not fully engage but the car will move but the trans wont fully lock up untill an rpm between 2300-2700 rpm. I have a 2800 stall now and when it's cold it slips it kinda acts like you are draggong the clutch out. Once the trans is warmed up low speed slip is minimal . The whole concept is when you floor it the converter will flash/engage at peak tq. rpm.

Tony72Cutlass'S'

Oh that's pretty cool,

Hey by the way I figured out my rough shifting problem. My modulator line was broken and it was leaking air

coppercutlass

I had that happen twice lol.

coppercutlass

Ok @ matt69olds. This might sound like a dumb question but do I use the stock separator plate with the b&m plate ? I did do some more assembly today but not much . I did the manual link shaft and park pawl rod. 1-2 accumulator piston, and installed the one check ball I need and a servo. Also new converter came in.

Greg Rogers

I'm not a transmission expert but I have rebuilt 2 turbo 350's and 1 Chrysler 727. I had a great big work bench made out of saw horses and a 4x8 sheet of plywood- covered with a old sheet. So lots of room and clean. I laid everything out in order as it came out and used the factory manual and the B&M instructions. The 1st one was the 350 in my 71 Cutlass. It was working when removed so I knew there wasn't any problems. I used the B&M Transpac in that. I made a few "special tools" such as a tee made with 2x4s and a notch in it to compress the springs on the clutch pack that's the rear. Used my big gut to compress while reaching in to remove/reinstall the snap ring..etc. Came out just fine. Did the Chrysler a few years later and it's been fine. The 2nd 350 was for my 70 Vista which really is a beater. Trans was inop in that one but I cheaped out and bought a no name kit off ebay . Actually I measured the end play and I was supposed to replace a thrust washer but I didn't and it too works okay. Of course these 2 Olds are stock and not race cars-(the Mopar is..) but my point is I think you will do ok and enjoy the accomplishment.

matt69olds

Every TH350 shift kit I have ever installed included a new spacer plate. If the kit includes the gold and silver transfer plate a new spacer plate is required. If you compare the stock and new plate you will find 2 added holes under the transfer plate, and a couple deleted holes near the accumulator. Did you get instructions with the shift kit?

coppercutlass

That's what I thought., it just said to use the old separator for reference on a hole and it confused me lol .

coppercutlass

The blue ox is done lol. Long story on the tail shaft but I had to use a different one lol. I think that john deer stencil dates back to my freshman year in high school when I made it for a tool box we made in metals class lol. I tested it on this trans lol it was always blue I thought about painting it but it gives it character lol. Also the modulator is a stock one ? adjustable. is there a difference between like a red stripe or is it the difference in vac. rate ? Not trying to cheap out but if I don't need it why get it .

coppercutlass

I also plan on installing this the weekend after next . I need new u joints installed in my th350 drive shaft and I need to also get it balanced.

matt69olds

The red and black stripes on the modulator do mean something, I just don't know what the difference is. I have always used the red stripe with no issues. Good luck!

coppercutlass

Thanks. I think I can re use the one from my th400 it is a red stripe.

coppercutlass

Ok guys im getting ready to try this out pretty soon going to install next weekend as long as I get my driveshaft back from my buddy and I get my cooling system done. I have one question for the trans gurus here. Will an ac condenser work for a tranny cooler? The reason I ask is because I have a few piled up at work that had to be replaced but do not leak the where just bent a lil bit from front end collision accidents. In theory I think it should work I just don't know if anyone has done this if it's overkill I don't mind because the condenser will mount nice in front of the radiator just like the stock ac condenser.

VinMichael

Including specialty, which tools were needed for this particular build? I have a th350 sitting on a shelf that I have been wanting to rebuild. Read Ron Session's book and watched a bunch of videos on it. Sometimes the tools listed are not always necessary and I'd like to avoid buying them if I can.

coppercutlass

I made my own tool to check the pistons , I bought snap ring pliers and the reverse piston removal tool , there is a special seal installed had I know about it I would have bought it. My friend had a lathe so we machined the pistons to hold 5 clutches. I'm still yet to install my th350 . If anything fails I'm pretty sure its going to be something seal related everything else is really hard to screw up.

76olds

I totally missed this thread, impressive pics and a well done job, Much credit to your ability to tackle something I could only dream to do. Put-r-ther awesome job.

coppercutlass

Thanks 76olds I want to build up another one but I want to do my own shift kit and more mods but re use the clutches I took out of the one I built since they where still within spec. The core I have appears to be low milage as well I have 2 more cores. So that will be a no buck build lol. I just like messing with stuff.

76olds

With regards to the shift kit a friend of mine previously owned the mister transmission In town here and he did mine simply by drilling some holes of my original whatever you call that plate then adjusted something on the side of the trans, put me a new filter and gasket it works great, bought him a bottle and drank one together after the job lol, best deal I ever got. Awesome guy, he was killed in a snowmobile accident last winter. He certainly helped me over the years!! Good luck with your next tranny !!

coppercutlass

Ok so I thought I would follow this thread up. I took the trans to a local builder who buildssome top notch stuff out of is garage awesome guy. I traded him my th400 for him to inspect my trans. He aid I did everything correct except the valve body gaskets I flip flopped them by mistake. So aside from the gasket everything was good and now iknow what to do. He also explained to me the weak areas ,Cheap upgrades I can do , and how the whole assembly works whats engaged and whats now engaged through out the transmissions operation.

TexasT

http://www.nastyz28.com/forum/showthread.php?t=53671

Jake used to be pretty helpful on many forums but I guess his business is taking a lot if his time. His posts are generally chocked full of knowledge.
I've not taken a th350 appart but the 2004r sure has a lot of parts in there.

coppercutlass

What I was told is the th400 is easier than the th350 . I might buy a 200r4 core just to mess with it. I thoroughly enjoyed building my trans. It was like building a model car lol lots of parts.