No 3rd Gear 727

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mitch340Duster

mitch340Duster

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1970 Duster fresh restoration so no history available. I rebuilt the trans. I've done 2 or 3 before and never had a problem. New Hughes converter. Low is fine, Reverse is fine, 1-2 shift is nice, but no shift into 3rd. Linkage is adjusted correctly. I went through the valve body completely again. Found that for the pressure relief I put the spring atop the ball instead of the ball on the spring. Figured I'd be all-set. No change.
With the wheels off the ground I revved it pretty good but still no 2-3 shift. adjusted throttle pressure some and still no change.
For road test I disconnected the throttle pressure since if I remember right it should still shift manually without it. Same thing, nice crisp 1-2 shift but no 2-3.
Car runs bad and is dangerous to drive now because of steering box adjustment and no front end alignment so at this time I cannot lean into it on the road but as I said with the wheels off the ground it still won't shift even at at rpm's of 3,000-ish.
Thanks for the help. This was a difficult topic to get good search results on.
 
Mitch, did you do an air pressure test before fitting the valve body? This normally uncovers any mishaps that might have unnoticeably occured during assembly.

I had a similar problem with a 727. It was a cracked sealing ring on the reaction shaft support.
Regards. Gaz
 
Gaz, Yes and no on the AP test today (long story).
I did do a test earlier in the assembly. I was confident about the results of one of the (clutch packs?) but skeptical about the other. Another long story. Our local trans guru looked at it and he said it was fine so I moved forward, but as I said I was still unsure.
Anyhow...you had the SAME problem? Lots of guys say that if you have reverse you should have forward, but maybe having low and reverse but no 2-3 shift is another story. Most folks also say to look for a valve body problem but I'm confident I've ruled that out.
I had a lot of issues with this rebuild and had to replace drums and blah blah blah. If you think based on my symptoms this could be something other than the valve body then I'll prolly just yank this thing this winter and start over. Ciao and thanks a lot.
Also, I have a video somewhere of the earlier air pressure test. if I can find it I'll throw it out there for opinions. Thanks again.
 
did you hook up a pressure gauge to the front servo test port and run it up to speed? That will at least narrow it down to whether its in the VB or not.
 
If you have 1,2 and reverse it a valve body or governor problem .I would start with the governor make sure it not sticking and the sealing ring are not worn or damaged .
 
william said:
If you have 1,2 and reverse it a valve body or governor problem .I would start with the governor make sure it not sticking and the sealing ring are not worn or damaged .
Click to expand...

Agreed. If it has 1st and 2nd the rear clutch is working and if it has reverse the front clutch circuit is working. Either has to be a governor or VB issue.

One thing that causes no 3rd a lot is guys get the 3/8" bypass check ball mixed up with the 11/32" check ball in the valve body. The 11/32 ball will sit in the bypass spring and the 3/8 ball sits in the VB channel but when you bolt the VB together it's too fat to move. I attached a PDF picture of the valve body showing the orientation of the check balls. The upper right picture is the one to look at
 

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  • Torqueflite Non-LU VB 1.pdf
    1.1 MB · Views: 359
I love when you chime in on these threads "fishy". I've learned enough from you over the years that if I live long enough, I may actually try to build one of these contraptions on my own.....then again, :D:D:D
 
OldmanRick said:
I love when you chime in on these threads "fishy". I've learned enough from you over the years that if I live long enough, I may actually try to build one of these contraptions on my own.....then again, :D:D:D
Click to expand...

LOL... Ya ought to give it a try Rick. I'd bet you'd have no trouble whatsoever doing one.
 
Fred...No, I'm not familiar with that procedure but I'll look into it next time. Thank You.
Fishy the balls are correct I noticed the difference.
FWIW this is a "non part throttle VB" but is not original to the tranny. I don't remember why I had to replace it.
I misunderstood about the governor, thinking that it was part of the VB but now I see in the Munroe book that it's in the tailshaft. Looks like this is an "in the car" operation. (?)
I will look at that ASAP but it'll be a few days at-least.
Finally for now, Rick ignore guys like me with weird problems and do a tranny sometime. This is my 4th and the only one that ever gave me any trouble. Did my 1st one when I was 20 and even more clueless than I am now. Forgot to install the front seal which was unpleasant (one of those mistakes I'll never make again) but after another R&R it worked great, plus when you tell guys you did your tranny they bow-down to you.
 
Still no change. Went-through the governor yesterday. Didn't see anything obvious with it but I cleaned it good and there's still no 2-3 shift. I think I might just drop the tranny and start over on this thing. My only other concern is that this was an Ebay VB. I don't remember why I had to replace the original one. Maybe there's something weird going on with it but I've been through it twice now using the FSM and the Munroe book and it all looks good to me. If you have any ideas I'm listening otherwise I'll pull the tranny in the fall. Thanks again for your time.
 
Mitch, it sounds like you're gonna have to get inside the trans again if you are sure the VB & govenor are ok. When you tear into it, inspect the sealing rings on the reaction shaft support. Also take the clutches, steels, & piston out of the front clutch drum and check the sealing lip on the rubber seal on the clutch piston.
If, as you say the VB & govenor are up to scratch, then I am pretty sure you have in internal hydraulic leak in the front clutch circuit which is small enough not to really affect reverse, due to the increased line pressure in reverse gear, but large enough to prevent 3rd gear engagement.
Cheers. Gaz
 
drop the VB and air test the direct clutch before you pull it all out again if you want to verify that is not an issue.
 
FredS said:
drop the VB and air test the direct clutch before you pull it all out again if you want to verify that is not an issue.
Click to expand...

As mentioned earlier the direct clutch is also responsible for reverse. No direct clutch=no reverse. He says he has reverse. Has to be a VB problem. Probably a jammed 2-3 shift valve. I'd stick a different valve body in it before I yanked the whole dang thing out. Changing a valve body= 1~1-1/2 hrs. max. Yanking it all back apart = at least a days work and it's obvious the major components have to be working since it has reverse, 1 and 2
 
Ah man i just had a long story almost complete and I lost the page. Bullet points...
Trans MIGHT have had a PTKD in it when I got it but it has non-PTKD now. I might have changed it thinking that the PTKD was the wrong one for the trans.
Trans date code is 9/69 (2961) yet the part number is 3410769 which is listed for "1970 Late" which makes no sense to me. Also 70-71 parts book shows only non PTKD valve body so I'm confused.
Maybe none of this matters anyhow, since it looks like you can add the PTKD section to a non PTKD body.
Anyhow, I'm gonna go with a different VB when I find one. I think I'd like to have the PTKD since it's a mild street car, and also the reverse lights didn't work because the comb did not contact the switch correctly. Fixed it with the Dremel tool but i don't want it coming back to haunt me.
I was gonna drop the pan to drain it anyhow before pulling the trans which is the worst part of the VB job. Mize well spend another 2 hours trying another VB at that time, and I'll do a more thorough air pressure test too.
Thanks for everyone's help. I will post an update when I do this, but it might not be until October.
 
Problem "solved". Nearly a full year after having this problem I finally had time to get into it again. Without doing any further investigation I got a new valve body from Cope Racing Transmissions. 1-2-3 shifts on first test drive followed by a "yesssss" that was probably heard by all the neighbors.
I don't know WTH with this thing. Another thing I noticed is that the VB provided by Cope was different than what was in-there. The "valve cover plate" on the old one has 4 screws, and the Cope VB's has 6 screws. Maybe someday I'll take a 3rd look at it. Thanks again for everyone's input.
 

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Glad you got it. The one you got from CRT is a newer version. Yours is a 70 or older style without part throttle kickdown. The newer version has ptkd and a few other minor changes
 
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