Slip and slide transmission

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Well I found the problem. It wasn't the second gear band, but the direct clutch. The good news is that most everything looks to be in good shape. I was not looking forward to replacing the bushings. The only wear I found outside the clutches was the planetary thrust washers. Turns out not many places carry them for the 60's trans. Hopefully they don't take too long to come in the mail.

In addition to the bushings, I found additional evidence that the trans has been through before. It had a bolt in spray, and already had a 4.2 lockdown apply lever.

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Wow! Those clutches have seen some excessive heat. A typical result of a maladjusted throttle pressure (Kickdown) linkage/cable. As CFHJ stated, put in 5 thin frictions in the rev/high clutch drum along with Kolene steels. If you are going to run at high RPM, a reverse wound front clutch return spring as Nick suggested is advisable, or you can go with the bells & whistles multi spring unit fron A&A . Part # K12985BA.
BTW. if you have a reprogramming kit in that transmission I would highly recommend getting rid of the puny low/rev servo piston spring retainer & replace it with a billet aluminium piece. Otherwise you might just surpisingly one day have no reverse gear!
One other thing. Make sure you order thrust washers for aluminium planetaries. if you order the ones for steel planetaries, they won't fit.
 
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I purchased the rebuild kit as recommended from transpartswarehouse, it was prepackaged with 4 clutches (alto red eagle). I did notice some debris in the clutch pack, I may find a torn seal on the direct clutch piston. I did order the reverse wound spring and the sonnax rear servo. High RPM is not likely, but it can't hurt and the spring was cheap.
 
Those four frictions are probably grooved as well. You'll be losing about 25% strength by using four grooved instead of five smooth. I have actually measured and computed the friction surface area lost with grooves. But this is what they package; and act like this is the accepted practice for performance. Like I keep saying; there is no kit available; you have to buy separate components. Sometimes I'm sent thick or grooved Red Eagles for 904s and 727s. I send them back. OEM plates are thick and grooved because they can't take the heat otherwise. "High performance" kits should have five smooth thins with an extra steel in them.
 
CudaFactHackJob said:
Those four frictions are probably grooved as well. You'll be losing about 25% strength by using four grooved instead of five smooth. I have actually measured and computed the friction surface area lost with grooves. But this is what they package; and act like this is the accepted practice for performance. Like I keep saying; there is no kit available; you have to buy separate components. Sometimes I'm sent thick or grooved Red Eagles for 904s and 727s. I send them back. OEM plates are thick and grooved because they can't take the heat otherwise. "High performance" kits should have five smooth thins with an extra steel in them.
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All my kits from transparts have had smooth clutches. The grooves on the clutchs may cause some surface area loss, but with the grooves any fluid between the clutchs can escape faster on lockup, this causes the initial clamp to be quicker and lessen the duration of the slip. Less heat overall.
 
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So the throttle valve was not the issue. Seal was gone on the direct clutch piston. And the alto reds are smooth. No grooves.

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Heres a good tip for piston install so you don't rip the seal. Grease the drum with vaseline or trans build lube. Put the seal on the piston and wrap it pushed down tight with electrical tape. Then freeze it for like 20 minutes. Take it out, pull the tape of, the seal will be flush and the piston will go right in with no tools. Zero damage every time.
 
Way ahead of you! I wrapped it with a rubber band and put it in the freezer. I just shouldn't have smeared the seal with trans gel before freezing it...
 
Thought I would give an update. I got everything wrapped up last Friday. Started up the car on the lift and didn't get movement in any gear! I put a gauge on the line pressure port, and only have pressure in manual low. 75 psi jumping to 100 psi when the throttle lever is pulled back. All the clutches were air checked. My only guess is I screwed up when reassembling the valve body. I'm on vacation this week, I have to drop the valve body when I get back.
 
Found the problem and it's not in the valvebody. Turns out my trans has a 18 spline input, and I ordered a 27 spline converter (which it's supposed to have). So either someone used early parts to rebuild this trans in the past, or I have an early built car using leftover '67 parts. I also noticed when installing the shift kit that it was missing some elements in the valvebody that were listed as being 68 and later.

So some quick searching has shown that there are not many options for 18 spline converters. Tflite patty on ebay has a high stall reman, and I would also need his spacer to get the small snout centered in my crank.

I could also flush my old converter, it shows almost no wear on the snout.

Last option is try and convert to the more common 27 spline. I'm not sure how much parts that would require.
 
indirect_connection said:
Found the problem and it's not in the valvebody. Turns out my trans has a 18 spline input, and I ordered a 27 spline converter (which it's supposed to have). So either someone used early parts to rebuild this trans in the past, or I have an early built car using leftover '67 parts. I also noticed when installing the shift kit that it was missing some elements in the valvebody that were listed as being 68 and later.

So some quick searching has shown that there are not many options for 18 spline converters. Tflite patty on ebay has a high stall reman, and I would also need his spacer to get the small snout centered in my crank.

I could also flush my old converter, it shows almost no wear on the snout.

Last option is try and convert to the more common 27 spline. I'm not sure how much parts that would require.
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A lot of 68 cars have 67 parts in them. The pump is driven off the drive hub and not the input shaft. One would think you'd still have more pressure than you did even with the input shaft not spinning. Tflite patty(Pat Blais) is in my state, he's legendary among tflite builders here and is great to work with.
 
Reinstalling the stock converter fixed the problem. Factory drain plug allowed me to flush out the clutch deposits. The shifts don't seem that much firmer, but I was not able to really get on it as I was just cruising around on Memphis side streets. Don't really want to go wide open from a standstill either. I want the 7 1/4 to survive until the 8.8 is built. I would be interested in comparing the mods done on a Tf2 kit, but I haven't seen the instructions posted anywhere.
 
indirect_connection said:
Reinstalling the stock converter fixed the problem. Factory drain plug allowed me to flush out the clutch deposits. The shifts don't seem that much firmer, but I was not able to really get on it as I was just cruising around on Memphis side streets. Don't really want to go wide open from a standstill either. I want the 7 1/4 to survive until the 8.8 is built. I would be interested in comparing the mods done on a Tf2 kit, but I haven't seen the instructions posted anywhere.
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I have them hold on a sec.
 
indirect_connection said:
Reinstalling the stock converter fixed the problem. Factory drain plug allowed me to flush out the clutch deposits. The shifts don't seem that much firmer, but I was not able to really get on it as I was just cruising around on Memphis side streets. Don't really want to go wide open from a standstill either. I want the 7 1/4 to survive until the 8.8 is built. I would be interested in comparing the mods done on a Tf2 kit, but I haven't seen the instructions posted anywhere.
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