727 issue i think?

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RobertP said:
This is what I was afraid was going to be the issue. I purchased the valve body and converter and bolt in sprag then took the trans a very well know trans builder in my area he took care of the assembly knowing what the car was going to be used for. It was built probably 10 years ago and probably less than 3000 miles on it since. It was spot on when I pulled the top end apart a year ago. Now that it's running again I've noticed this. I will adjust the linkage again to verify. Any tricks to that other than having someone in the car while it's on the lift and me adjusting it on the trans?
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Adjusting the front band (I'm not talking about shift linkage) is easy, provided you can get to the adjustment past the headers, which I assume you have headers on the car. The adjustment doesn't require anyone in the car. The adjuster is located on the drivers side about 2 inches above the shift linkage. It looks like a stud sticking out with a locknut on it. What you need to do is hold the stud and back off the locknut then turn the stud counter-clockwise 1/4 turn then tighten the locknut and test drive it. If backing it off 1/2-3/4 turn doesn't solve it chances are it's not an adjustment issue. Possibly a broken spring in the front servo. A valve body leak like A/J mentioned is also a possibility. It's possible the builder didn't torque the valve body correctly and it worked loose and is leaking from one circuit to another. Dropping the pan for an inspection would reveal if that's the case.
 
tarvin890 said:
This is news to me... in my dragster burnout was in 2nd... why would a street car do a burn out in 2nd and not start in 1st? Im curious...dont want to hurt my trans... if its bad im glad i stmbled on this thread...
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The OP was told no burnouts in 1st gear because he has a manual valve body with no low band apply (same thing a race car uses) which puts all the load on the sprague. If the sprague isn't a aftermarket bolt in style it can spin in the case and let the front clutch spin about 2.5 times the rpm of the engine. Stock front clutch carriers usually explode like a bomb when that happens. A factory valve body has low band apply so it's not as critical to worry about 1st gear burnouts because the rear (low) band shares the load with the sprague supporting it. IMO 1st gear burnouts are really never a good thing unless you immediately shift to 2nd when the tires start spinning and don't downshift until they've stopped spinning
 
fishy68 said:
Adjusting the front band (I'm not talking about shift linkage) is easy, provided you can get to the adjustment past the headers, which I assume you have headers on the car. The adjustment doesn't require anyone in the car. The adjuster is located on the drivers side about 2 inches above the shift linkage. It looks like a stud sticking out with a locknut on it. What you need to do is hold the stud and back off the locknut then turn the stud counter-clockwise 1/4 turn then tighten the locknut and test drive it. If backing it off 1/2-3/4 turn doesn't solve it chances are it's not an adjustment issue. Possibly a broken spring in the front servo. A valve body leak like A/J mentioned is also a possibility. It's possible the builder didn't torque the valve body correctly and it worked loose and is leaking from one circuit to another. Dropping the pan for an inspection would reveal if that's the case.
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I will give this a shot Friday once the exhaust goes on. Probably going to be dropping the pan to change fluid and filter anyway I will check the torque on the valve body while I'm in there. Anything else to be on the lookout for other than obvious signs of metal or clutch material? I will most likely perform the front band adjustment as you stated prior to dropping the pan. I appreciate all the input.
 
fishy68 said:
The OP was told no burnouts in 1st gear because he has a manual valve body with no low band apply (same thing a race car uses) which puts all the load on the sprague. If the sprague isn't a aftermarket bolt in style it can spin in the case and let the front clutch spin about 2.5 times the rpm of the engine. Stock front clutch carriers usually explode like a bomb when that happens. A factory valve body has low band apply so it's not as critical to worry about 1st gear burnouts because the rear (low) band shares the load with the sprague supporting it. IMO 1st gear burnouts are really never a good thing unless you immediately shift to 2nd when the tires start spinning and don't downshift until they've stopped spinning
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i thanks for the info.. i dont have a stock trans either and glad i learned this...save my trans...lol
 
RobertP said:
I will give this a shot Friday once the exhaust goes on. Probably going to be dropping the pan to change fluid and filter anyway I will check the torque on the valve body while I'm in there. Anything else to be on the lookout for other than obvious signs of metal or clutch material? I will most likely perform the front band adjustment as you stated prior to dropping the pan. I appreciate all the input.
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cant wait to see what the fix turns out to be.... let us know!
 
RobertP said:
with the manual valve body there are no adjustments on the carb linkage for throttle pressure.

i have checked and rechecked my shifter linkage for going in and out of gear and all seems right. went as far as to replace the shifter cable as well. it shifts into second and pulls hard with no issues when at wot. this is just at slow cruising when it feels like it is dragging. video at wot thru second.
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Yep sorry, I missed the manual valve body part somehow.
Just a side note that didn't get answered yet, I take the linkage loose from the trans lever and put the shifter and the trans in each gear one at a time and make sure the shifter linkage and the trans linkage lever both match at each position.
This is the most effective way I have found to verify the correct linkage geometry.

Myself, I think since you have a manual valve body the problem is actually still there at WOT, but you may be just powering through it and not feeling it. (Really hard on the trans)
I also think that if you find nothing else wrong, that checking/changing band levers should do it like Tracy said. (You want to speed up the release of the band either with the lever or by getting the fluid out of the servo faster) and the lever is the easier way.
 
RobertP said:
I will give this a shot Friday once the exhaust goes on. Probably going to be dropping the pan to change fluid and filter anyway I will check the torque on the valve body while I'm in there. Anything else to be on the lookout for other than obvious signs of metal or clutch material? I will most likely perform the front band adjustment as you stated prior to dropping the pan. I appreciate all the input.
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I think that covers things. Let us know how it goes
 
Ok so I had my exhaust done today and trailered it to the shop. Drove it home and didn't have one issue. I didn't change anything?? The only change was going from open header to 3 inch all the way out the back. Went into second and no dragging or holding back at all? What the heck is going on?
 
RobertP said:
Ok so I had my exhaust done today and trailered it to the shop. Drove it home and didn't have one issue. I didn't change anything?? The only change was going from open header to 3 inch all the way out the back. Went into second and no dragging or holding back at all? What the heck is going on?
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Nothing obviously. :D

Sorry, I had to.

Could it possibly be fluid temp that is making the difference?
(Like cold fluid releasing the band slower than hot fluid)
 
So the tranny problem previously described was running with open headers?

If that's the case, open headers can create A/F issues that can seem like tranny issues. Especially when load puts the carb into a transition between fuel circuits.
 
I had this issue a few months back and forgot till it happened last nite.... i shifted into second and the car started slolwing like the brakes were applying... i shifted back into 1st and came back to 2nd and all was fine....im thinking its what you are talking about on yours and im preety sure my shift cable/ linkage is out of adjustment like someone above stated... what kind of shifter are you using? could it be out of adjustment? if so this could account for the periodic acting up...
 
I'm running a B&M pro ratchet. The shifter doesn't have any adjustment it's all in the cable. But if it isn't in a preload ratchet position it could be in between gears that's a very good possibility.
 
Also took it on a a nice 45 minute ride with no problems in and out of all the gears multiple times and ran perfect. All was great except the fuel gauge hahaha
 
RobertP said:
I'm running a B&M pro ratchet. The shifter doesn't have any adjustment it's all in the cable. But if it isn't in a preload ratchet position it could be in between gears that's a very good possibility.
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i have the hurst qtr stick... i believe the cable/shifter linkage and be out slightly and cause this.... mine did it @ 3 months ago.. and again last nite... i immediately thought of this thread...maybe when they put is on the lift it tweaked a bit and made it better...for now... i know mine needs adjusting... let everyone know if it happens again or if you find anything else out...
 
I have found that with the ratchet action if you don't set it back into fist and then pre load the shifter to shift to second it will actually not make the full shift. That is when this occurs. Down fall of a ratchet shifter I just found out.
 
RobertP said:
I have found that with the ratchet action if you don't set it back into fist and then pre load the shifter to shift to second it will actually not make the full shift. That is when this occurs. Down fall of a ratchet shifter I just found out.
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Keep the geometry in mind also, as just because we put the lever in neutral and the linkage for the shifter lines up right in neutral doesn't mean it lines up right for every other gear position.

I just changed to a rubber/steel gasket recently and it messed the linkage alignment ALL up. :D
 
RobertP said:
I have found that with the ratchet action if you don't set it back into fist and then pre load the shifter to shift to second it will actually not make the full shift. That is when this occurs. Down fall of a ratchet shifter I just found out.
Click to expand...

Not all ratchet shifters are that way. I have a B&M quicksilver in mine and have no problems. I'd check the adjustment like the others said. Wouldn't hurt
 
well i re adjusted it and it worked great with the ratchet shifter. but i could also get it stuck between gears and don't want to take the chance of ruining my trans. installed the Cheetah SCS shifter this weekend and it works perfect every time now.
 
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