transmission guys, need a little help

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this hasnt come up in a while, but i need some guidance.

im having a 1-2 shift overlap issue. Ive adjusted the front band to a couple different specs (2 and 2 1/2 turns out) but it is not helping. what im looking for is a step by step instruction on what i need to do to get rid of this , or at the very least minimize what is happening before i jack something up. pics would be invaluable. ive searched youtube and i cannot find any info dealing with this exact problem. this car is my daily driver so pulling the trans is not an option (unless i break it) and im not looking to buy a shift kit (unless i have to), only to remedy the problem. im hoping to pull the pan off only once and get it right the first time, unless there is a way to do this without pulling it off at all.

a little background. this is a 67 727 that is behind a stock 318 out of a 67 coronet. i have never had the pan off and i am assuming it has been rebuilt and has factory internals with no shift kit. im also assuming it has an 11" converter. the fluid looks, smells and tastes (lol) normal and is exactly full. this trans never slips or makes any unusual noises and does not leak. i am using 2 quarts of type F mixed with Dex 3 of which is 2 years old and looks fresh . the fluid that was in it was very good. the trans works great under normal operating conditions, it does not "bang" gears, although when i get in to the four barrels, it will get a 1-2 bark on pavement when the shifter is in drive, also, when i put it in drive, it shifts through all the gears like it should, downshifting and upshifting very well and feels as though it is working properly. when i take off in first gear and attempt to manually shift it into second gear, it bogs down for about 3-5 seconds before it shifts and second is sluggish to get going and feels like it is not completely getting out of first gear when second engages. this REALLY bothers me and im not trying to burn up this transmission. 2 -3 shift is great. i have stopped taking off in first altogether and i only use drive. will this trans eventually self destruct ? or is it OK to use it with the shifter in drive? i really need to fix this as i have been attending to other areas, but now its time.

ive heard of some kind of accumulator or servo mod that can fix this , but i have no idea where to start. i am a novice when it comes to transmission internals, but im sure this is nothing i cant handle.

sorry for the long winded post , but im trying to be as clear as i can. thanks in advance , i really need some good, clear instruction here. :D
Lance
 
If it shifts fine in auto then it's probably in the valve body or modulator circuit.
That is assuming the fluid looks good and clean (not burned or dark)
I would suspect that manually shifting it like this will ruin something.

What do you think Tracy?
 
Sounds to me that your rear reverse band is to tight.When you put it manual low the rear band apply's to support the rear roller clutch.If the rear band don't release fast enough it will tie up causing a binding condition.
If it barks the tires from first to second it may have a shift kit,or someone modified the valvebody.
I would check the rear band adjustment try backing the throttle pressure back a little to see if that helps.
 
thank you guys for your info. im gathering all i can before i dive into it. if i have to buy a shift kit to fix it i will , but im not sure if that will do any good. the way it shifts now, its possible there may be one in it, but im not going to tear into it until im armed with all the necessary parts and information i can possibly get , because i wont have a way to go anywhere if i have to.
 
He's right Lance.
I forgot about that. (Thats why they call it a "low reverse band")
Pan comes off to do it, but not the valvebody
Sure would be worth a chk and adjust.

Thanks BRONZEBEE
 
that is definitely on my list now. if that doesnt do it is there anything else i can do while im in there to insure i will be good to go before i put it back together?

thanks guys
 
band adjustments are 2 on the front and 3 on the rear. those early valve bodys use to crack around the pressure regulator causing internal leaks.
 
zijmer said:
band adjustments are 2 on the front and 3 on the rear. those early valve bodys use to crack around the pressure regulator causing internal leaks.
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thanks on the adjustments. i hope this thing isnt cracked. would it be visible with the pan off or would i have to drop the VB to see it?
 
If TV/kickdown rod not proberly adjusted you may be getting overlap on the 1to 2 upshift na d by the same token your off throtte dowshift may be very harsh znc slap back to first gear:supz:tp
 
73AbodEE said:
thanks on the adjustments. i hope this thing isnt cracked. would it be visible with the pan off or would i have to drop the VB to see it?
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no such luck. you have to pull it off and split it. i wish i had picture to show you. sometimes its hard to see.
 
Lance my guess is the problem is the common one with the rear servo. It has an internal cushion spring that compresses as the outer spring is extending making the servo slow to release. It's there to ease the release of the rear band but it's really a hinderance. It doesn't show up when the trans. is driven in drive cause the rear band servo isn't applied. The Trans-go shift improver kits (and some others) have a spacer that you install in the rear servo to eliminate the action of the one spring working against the other and it generally eliminates the overlap problem. Do you still have the Trans-go info I sent you? That was you I sent it to a few months back, wasn't it? If so it shows installing the spacer. I have always used the Trans-go kits spacers but I imagine you could make one pretty easy if this is your only complaint. ACE hardware sells a lot of different spacers too. They might have something you could cut down and make work. Whatever you do make sure and get it remedied quick cause overlap is a trans. killer and yours sounds bad.
 
fishy68 said:
Lance my guess is the problem is the common one with the rear servo. It has an internal cushion spring that compresses as the outer spring is extending making the servo slow to release. It's there to ease the release of the rear band but it's really a hinderance. It doesn't show up when the trans. is driven in drive cause the rear band servo isn't applied. The Trans-go shift improver kits (and some others) have a spacer that you install in the rear servo to eliminate the action of the one spring working against the other and it generally eliminates the overlap problem. Do you still have the Trans-go info I sent you? That was you I sent it to a few months back, wasn't it? If so it shows installing the spacer. I have always used the Trans-go kits spacers but I imagine you could make one pretty easy if this is your only complaint. ACE hardware sells a lot of different spacers too. They might have something you could cut down and make work. Whatever you do make sure and get it remedied quick cause overlap is a trans. killer and yours sounds bad.
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Thank you Tracy. yes , i still have the PDF's you sent me. i was having a hard time understanding exactly what they are showing, but i see that there is a spacer. is there anyway of finding out the exact size of it? i can make one very easily.

do i need the 5/16 plug? and is the circled spacer the one we are talking about?
 

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I know a lot of people use washers to block the damper section, but don't know what size.
It would be easy to find out when your there.
 
what determines the "type 1" and "type 2" ? are these in the kit or is it the type of transmission? i was under the impression that all 727s are the same internally. it will be simple for me to get the diameter of the spacer, but i need to know how tall it is
 
i got a new filter and more fresh fluid today. i will be set to break open the pan in the next couple of days.
 
There are two different gears . Low and then first. If you pull out in low and shift you will get overlap as you call it. Try pulling out in drive (first gear) and before it shifts on its own pull it back to low then shift second . you'll feel the difference. Low gear select is low band apply. drive is first gear.
 
well, i dropped the pan. fluid looks new. a little pile of metal in the pan and a little on the filter, but i have seen worse.

but then there is this little metal? thing, kind of looks like a needle bearing...not sure what it is , any ideas out there? the valve body appears factory, but i am by no means any kind of trans guy, in fact the is just about as deep as ive been into one lol.

sorry about the pics , the camera is horrible at close-ups.
 

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the rear band is already at 3 turns out. i guess im just going to put it back together and hope it doesnt blow up.
 
yeah that looks like a retaining pin of some sort , I would definitely want to know where that fell out of before I closed her up
 
Lance, is this piece hard and hollow like a roll pin or could it be just some rolled up band/drum material? Where's all the trans guy's opinions when you need'um.....lol.
 

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OldmanRick said:
Lance, is this piece hard and hollow like a roll pin or could it be just some rolled up band/drum material? Where's all the trans guy's opinions when you need'um.....lol.
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its all good Rick, i guess we dont have to many folks that do their own transmissions. it was brittle like a piece of wire casing or something weird. at first i thought it was a roll pin as well, but it snapped in two very easily. it may have just been some debri that got in there somehow. i adjusted the bands and put it back together, same problem, but screw it, i will just drive it till she blows :D
 
73AbodEE said:
well, i dropped the pan. fluid looks new. a little pile of metal in the pan and a little on the filter, but i have seen worse.

but then there is this little metal? thing, kind of looks like a needle bearing...not sure what it is , any ideas out there? the valve body appears factory, but i am by no means any kind of trans guy, in fact the is just about as deep as ive been into one lol.

sorry about the pics , the camera is horrible at close-ups.
Click to expand...
its a blury picture at best, but if it looked like alumimin and crumbled between your fingers, it may have been a machining chip that wasnt cleaned out.
 
zijmer said:
its a blury picture at best, but if it looked like alumimin and crumbled between your fingers, it may have been a machining chip that wasnt cleaned out.
Click to expand...

yes thats very possible, my camera is lame LOL . i will just drive it without shifting it manually, hopefully it will live.
 
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