TV cable adjustment damage

[Greywolf200]

I got a rebuilt 700R4 from a performance transmission builder and am having some problems. Reverse is good, first gear is good, 1-2 shift is good, second gear is good, but third gear doesn't pull. The TV cable is adjusted per the instructions on the Bowtie Overdrive site. Push the housing all in, wide open throttle and 3/8 to 1/2 slack at the carb. The builder is trying to say the problem is TV cable adjustment has damaged the tranmission. There has never been a 1-2 problem. What could the problem be and how can I know the builder isn't trying to charge me for waurranty work?

I appreciate any feedback, thanks.

[clinebarger]

Originally Posted by Greywolf200

I got a rebuilt 700R4 from a performance transmission builder and am having some problems. Reverse is good, first gear is good, 1-2 shift is good, second gear is good, but third gear doesn't pull. The TV cable is adjusted per the instructions on the Bowtie Overdrive site. Push the housing all in, wide open throttle and 3/8 to 1/2 slack at the carb. The builder is trying to say the problem is TV cable adjustment has damaged the tranmission. There has never been a 1-2 problem. What could the problem be and how can I know the builder isn't trying to charge me for waurranty work?

I appreciate any feedback, thanks.

Sounds to me like the 3-4 clutches are burnt up. I agree with the builder on a misadjusted TV cable/geometry can do that real quick, BUT its the builder/seller responsibility to tell you that there is no warranty if the TV cable is not adjusted correctly. The ONLY way to verify that is with a pressure gauge BEFORE you drive it. (2-4 lbs preload at idle, & bury the TV plunger at WOT) The #1 & #2 killers of the 700R4s 3-4 clutch pack are low fliud level. #3 is Low line pressure/line pressure rise when shifting into 3rd.

[shortbed70]

I was told to set my tv at wot for it to be tight. And to set it by pump pressure not just the feel of the cable. Sounds like trans is laying down.

[Greywolf200]

I live in Mayberry and the local trans shop isn't exactly B&M. They don't even have a pressure gauge to check the line pressures(I asked on a previous transmission they built for me and was disatisfied with). This is NASCAR country and performance is expensive. I ended up going out of state to get a good deal on a performance tranny. Where could I get a pressure gauge to check the next install when I get this one fixed?

Thanks,

[clinebarger]

Originally Posted by Greywolf200

I live in Mayberry and the local trans shop isn't exactly B&M. They don't even have a pressure gauge to check the line pressures(I asked on a previous transmission they built for me and was disatisfied with). This is NASCAR country and performance is expensive. I ended up going out of state to get a good deal on a performance tranny. Where could I get a pressure gauge to check the next install when I get this one fixed?

Thanks,

They dont have a pressure gauge! Thats crazy, I bet they have a $4000 scanner, But buying a $40 gauge is out of the question.
Heres some gauges, Any 0-300psi gauge & whip with a 1/8" NPT end on it will work.

http://www.finditparts.com/products/...-5550?cpao=114
http://www.etoolcart.com/transmissio...e-atd5550.aspx
This is what I have http://buy1.snapon.com/products/diag...s/eepv308a.asp

[Greywolf200]

[QUOTE=clinebarger;4550177]They dont have a pressure gauge! Thats crazy, I bet they have a $4000 scanner, But buying a $40 gauge is out of the question.
Heres some gauges, Any 0-300psi gauge & whip with a 1/8" NPT end on it will work.

Nope no $4000 scanner, he only got a transmission flush machine last November. Where can I find out what to look for when the gauge is attached?

This forum is the greatest!

Thanks,

[Wrenchbender Ret]

I set them so WOT pulls the cable out all the way. It is also important to have the cable hookup the proper distance from the throttle shaft & the right arc. About 1 1/8 in. is close to right.
I put one in one time & noticed it slipped in 3rd. I redid the position of the hookup on the throttle lever & it worked fine after that.

[clinebarger]

Originally Posted by Greywolf200

Nope no $4000 scanner, he only got a transmission flush machine last November. Where can I find out what to look for when the gauge is attached?

This forum is the greatest!

Thanks,

As Wrenchbender Ret pointed out, You will need some kind of geometry corrector when using carbs with a Ford style linkage (Edelbrock,Holley etc.) & pre 1980 Quadra-jets. I like using these http://www.bowtieoverdrives.com/cata...php?ITEMID=213

What you want is a 2-4 lbs preload at idle, & bury the TV plunger at WOT, With the cable unhooked the pressure reading is the minimum regulated pressure, You want 2-4 lbs above that with the cable connected.

After you do the WOT set procedure & you cant get the correct preload at idle....This means the TV spring is the wrong length for your set up (The BTO kit comes with a TV spring)

TV spring check procedure.
Make sure the engine is warmed up and off the fast idle cam or circuit. With the engine at normal idle, the pressure should be at minimum regulated pressure or slightly higher. You can determine whether the TV valve is positioned correctly or not with the next two tests. Write down the minimum observed pressure at idle, disconnect the TV cable. If the pressure drops, It is normally safe to drive the vehicle. If drops a lot (over 3-4 lb.), something is not correct in your system (TV spring to long). If pressure didn't drop when you disconnected the TV cable, reconnect the cable; gently pull the inner wire cable without moving the throttle linkage. If you can gently pull the cable any distance without instant pressure rise, something is seriously wrong(TV spring to short) This will lead to rapid clutch failure.

More on using a pressure gauge.

Using a pressure gauge can seem like a formidable task. The reason most people do not use a pressure gauge is because they do not see the value in using one. Technicians do not see the value because the gauge readings do not tell them how to fix the problem. This article will attempt to show the technician how to interpret pressure gauge readings so the technician can find the fix to the problem.

It is best to start pressure tests with mainline pressure. Mainline pressure should be checked in each range: P, R, N, D, 3, 2, 1. Each range, except Park and Neutral, should be checked under three conditions: Slow idle, fast idle, and wide open throttle. A form, as in figure 1 should be made to record the readings.

If all pressures are within specification at slow idle then the pump and pressure regulator are functioning properly.

If all pressures are low at slow idle, it indicates a potential problem in the pump, pressure regulator, filter, low fluid, or internal leakage. To help verify where the problem is, check pressures at fast idle. If all the pressures now read normally, it usually indicates a worn pump but the problem could still be internal leaks.

Internal leaks will usually show up in a particular range. For example a forward clutch leak would have normal pressure in Park, Reverse and Neutral but have low pressure in all forward ranges. A direct clutch leak will show a pressure drop when the transmission shifts to third and low pressure in reverse because in most cases, the direct clutch is on in third and reverse.

A restricted filter will usually show up as a gradual pressure drop at higher engine RPM because the filter cannot pass as much fluid as the pump is trying to draw.

A stuck pressure regulator valve will show up as fixed line pressure which means the same pressure all the time. The pressure may vary with engine RPM which means low pressure at slow RPM and higher pressure at higher RPM. There will be no boost in pressure from the TV or modulator system and no reverse boost.

If pressures are high at slow idle it indicates a pressure regulator or throttle pressure problem. On most cars, the modulator controls throttle pressure. If the transmission has a throttle pressure tap, it will tell you if the throttle pressure circuit is the problem. On GM units without a throttle pressure tap, remove the TV plunger. If line pressure is now normal then it's a TV problem, if not it's a pressure regulator problem.

Pressures also need to be checked at stall or wide open throttle (WOT). When doing a stall test, always observe safety precautions such as checking for broken mounts or bad brakes. Testing should always be done under operating conditions. To do a stall test, put the selector in the range to be tested and with one foot firmly on the brake, press the accelerator to the floor then note your pressure reading. Some technicians will pull the vacuum line off or pull the TV cable with the engine at fast idle. That is not operating conditions and will not detect a problem of trapped vacuum or a cable problem.

If all pressure at stall are low, then you should pull the TV cable to maximum or disconnect the vacuum line. If the pressures are now OK, the problem is in the cable or vacuum system. If the pressures are still low, then the problem is in the pump or control system.

If all pressures at stall are high, then look at the idle pressures. If the idle pressures are also high then this could be a pressure regulator or throttle system problem. If idle pressures are normal then the problem is in just the throttle system.

The reverse stall test is also a maximum pump output test. If you suspect a weak pump then this test will help find it. Often this will show up as low pressure at reverse stall but all other pressures including idle will be normal. If a person wanted to become really proficient with a pressure gauge they should first put a pressure gauge on their own vehicle and leave it there for exactly one week. Every time they drive the car they should watch the gauge. After one week, they should then put the pressure gauge on every single car in the shop that DOES NOT have a problem. Don't use the gauge on cars WITH problems yet. After 30 days of using a gauge on units that work properly, they can then start using the gauge on units with problems. The technician is accustomed to normal readings, abnormal readings will stand out like a sore thumb.

To fix today's transmissions, every professional technician must be proficient in the use of a pressure gauge. The only way to gain this proficiency is to use the pressure gauge daily. Practice makes perfect.

Pressure specs (700R4)

[Greywolf200]

[QUOTE=clinebarger;4552402]What you want is a 2-4 lbs preload at idle, & bury the TV plunger at WOT, With the cable unhooked the pressure reading is the minimum regulated pressure, You want 2-4 lbs above that with the cable connected.

After you do the WOT set procedure & you cant get the correct preload at idle....This means the TV spring is the wrong length for your set up (The BTO kit comes with a TV spring)

My TV cable has no preload at idle. There is between 3/8" and 1/2" of slack. I'm using an Edelbrock Performer with a cable adapter from Jegs. http://www.jegs.com/i/JEGS+Performan...57301/10002/-1

If I'm reading your right, my TV spring is the wrong length for the Jegs cable adapter?

[clinebarger]

Originally Posted by Greywolf200

My TV cable has no preload at idle. There is between 3/8" and 1/2" of slack. I'm using an Edelbrock Performer with a cable adapter from Jegs.
If I'm reading your right, my TV spring is the wrong length for the Jegs cable adapter?

The TV cable (inner wire) could be to long for your set-up. http://67-72chevytrucks.com/vboard/s...d.php?t=402683 #2 post.

[Greywolf200]

Originally Posted by clinebarger

The TV cable (inner wire) could be to long for your set-up. http://67-72chevytrucks.com/vboard/s...d.php?t=402683 #2 post.

I'll have to check this weekend to see how the geometry of the '84 carb compares to the adapter bracket. Would pushing the cable housing back into the bracket to achieve 2-4 lb pull accomplish the correct adjustment? As it is, 1-2 change is at a good speed.

[Richard H.]

Good posts Clinebarger , Graywolf in the last pic in this link...
http://67-72chevytrucks.com/vboard/s...5&postcount=48
it shows the BTO tv made easy if you look close. I had the universal crap on it before and it was cheap junk had to ty-rap the housing at the bracket to hold it. The black hose near the firewall is for the pressure gauge tester. A little pricey but good insurance for you and support from BTO.

[Greywolf200]

Mr. Clinebarger, the pressure chart is a great help. The BTO website gives a good description of the pressure testing procedure, but no pressure ranges. I've ordered a pressure gauge so will be ready for round two.

How many TV springs are available and how do you determine which one you need?

Thanks,

[clinebarger]

Originally Posted by Greywolf200

Mr. Clinebarger, the pressure chart is a great help. The BTO website gives a good description of the pressure testing procedure, but no pressure ranges. I've ordered a pressure gauge so will be ready for round two.

How many TV springs are available and how do you determine which one you need?

Thanks,

There is around 11 different length GM springs. Then aftermarket springs from Trans-go, BTO etc. Buying the BTO kit takes the guess work out. There is no way for me to know the exact spring you need, It sounds like yours is to short.....You can play with some longer ones untill you get it right, or buy the kit.

[Sick5]

when we burry our plunger at WOT. can we just pull our cable or do we need the throttle WOT as well?

Originally Posted by clinebarger

As Wrenchbender Ret pointed out, You will need some kind of geometry corrector when using carbs with a Ford style linkage (Edelbrock,Holley etc.) & pre 1980 Quadra-jets. I like using these http://www.bowtieoverdrives.com/cata...php?ITEMID=213

What you want is a 2-4 lbs preload at idle, & bury the TV plunger at WOT, With the cable unhooked the pressure reading is the minimum regulated pressure, You want 2-4 lbs above that with the cable connected.

After you do the WOT set procedure & you cant get the correct preload at idle....This means the TV spring is the wrong length for your set up (The BTO kit comes with a TV spring)

TV spring check procedure.
Make sure the engine is warmed up and off the fast idle cam or circuit. With the engine at normal idle, the pressure should be at minimum regulated pressure or slightly higher. You can determine whether the TV valve is positioned correctly or not with the next two tests. Write down the minimum observed pressure at idle, disconnect the TV cable. If the pressure drops, It is normally safe to drive the vehicle. If drops a lot (over 3-4 lb.), something is not correct in your system (TV spring to long). If pressure didn't drop when you disconnected the TV cable, reconnect the cable; gently pull the inner wire cable without moving the throttle linkage. If you can gently pull the cable any distance without instant pressure rise, something is seriously wrong(TV spring to short) This will lead to rapid clutch failure.

More on using a pressure gauge.

Using a pressure gauge can seem like a formidable task. The reason most people do not use a pressure gauge is because they do not see the value in using one. Technicians do not see the value because the gauge readings do not tell them how to fix the problem. This article will attempt to show the technician how to interpret pressure gauge readings so the technician can find the fix to the problem.

It is best to start pressure tests with mainline pressure. Mainline pressure should be checked in each range: P, R, N, D, 3, 2, 1. Each range, except Park and Neutral, should be checked under three conditions: Slow idle, fast idle, and wide open throttle. A form, as in figure 1 should be made to record the readings.

If all pressures are within specification at slow idle then the pump and pressure regulator are functioning properly.

If all pressures are low at slow idle, it indicates a potential problem in the pump, pressure regulator, filter, low fluid, or internal leakage. To help verify where the problem is, check pressures at fast idle. If all the pressures now read normally, it usually indicates a worn pump but the problem could still be internal leaks.

Internal leaks will usually show up in a particular range. For example a forward clutch leak would have normal pressure in Park, Reverse and Neutral but have low pressure in all forward ranges. A direct clutch leak will show a pressure drop when the transmission shifts to third and low pressure in reverse because in most cases, the direct clutch is on in third and reverse.

A restricted filter will usually show up as a gradual pressure drop at higher engine RPM because the filter cannot pass as much fluid as the pump is trying to draw.

A stuck pressure regulator valve will show up as fixed line pressure which means the same pressure all the time. The pressure may vary with engine RPM which means low pressure at slow RPM and higher pressure at higher RPM. There will be no boost in pressure from the TV or modulator system and no reverse boost.

If pressures are high at slow idle it indicates a pressure regulator or throttle pressure problem. On most cars, the modulator controls throttle pressure. If the transmission has a throttle pressure tap, it will tell you if the throttle pressure circuit is the problem. On GM units without a throttle pressure tap, remove the TV plunger. If line pressure is now normal then it's a TV problem, if not it's a pressure regulator problem.

Pressures also need to be checked at stall or wide open throttle (WOT). When doing a stall test, always observe safety precautions such as checking for broken mounts or bad brakes. Testing should always be done under operating conditions. To do a stall test, put the selector in the range to be tested and with one foot firmly on the brake, press the accelerator to the floor then note your pressure reading. Some technicians will pull the vacuum line off or pull the TV cable with the engine at fast idle. That is not operating conditions and will not detect a problem of trapped vacuum or a cable problem.

If all pressure at stall are low, then you should pull the TV cable to maximum or disconnect the vacuum line. If the pressures are now OK, the problem is in the cable or vacuum system. If the pressures are still low, then the problem is in the pump or control system.

If all pressures at stall are high, then look at the idle pressures. If the idle pressures are also high then this could be a pressure regulator or throttle system problem. If idle pressures are normal then the problem is in just the throttle system.

The reverse stall test is also a maximum pump output test. If you suspect a weak pump then this test will help find it. Often this will show up as low pressure at reverse stall but all other pressures including idle will be normal. If a person wanted to become really proficient with a pressure gauge they should first put a pressure gauge on their own vehicle and leave it there for exactly one week. Every time they drive the car they should watch the gauge. After one week, they should then put the pressure gauge on every single car in the shop that DOES NOT have a problem. Don't use the gauge on cars WITH problems yet. After 30 days of using a gauge on units that work properly, they can then start using the gauge on units with problems. The technician is accustomed to normal readings, abnormal readings will stand out like a sore thumb.

To fix today's transmissions, every professional technician must be proficient in the use of a pressure gauge. The only way to gain this proficiency is to use the pressure gauge daily. Practice makes perfect.

Pressure specs (700R4)

[clinebarger]

Originally Posted by Sick5

when we burry our plunger at WOT. can we just pull our cable or do we need the throttle WOT as well?

Always use the throttle to adjust the TV cable. You will hear the TV cable adjustor "click" when adjusting it.

[Sick5]

Too bad I have the universal cable that won't click.

But.my question was when taking the psi reading. Do I need to have the engine rev up to WOT. Or is it ok to take your measurement with just pulling on the cable

[clinebarger]

Originally Posted by Sick5

Too bad I have the universal cable that won't click.

But.my question was when taking the psi reading. Do I need to have the engine rev up to WOT. Or is it ok to take your measurement with just pulling on the cable

DO NOT race the engine to WOT in park, The valves would float or you will picking up connecting rods of the ground! The following intructions are with the engine OFF.

You have a Lokar style TV cable, OK, I guess it has some kind of crimp for the cable end?

Adjust the jamb nuts to center.
Slide the plastic end clip down the cable, then the crimp.
Hook the plastic end clip to the carb.
Clamp some locking pliers on the end of the cable.
Rotate the throttle lever to WOT (have someone hold it there).
Using the pliers pull the cable tight.
While keeping the cable tight, Push the crimp against the plastic end & crimp it/tighten it.

After installing the crimp, With the carb still at WOT, pull the cable again, if there is slack, Adjust the cable housing toward the firewall a little at a time untill the slack is no longer present.

[Sick5]

i have that part down.. thanks!
but when im doing the gauge reading with the car on the take the reading at WOT.. can i just pull on the cord to WOT and take the reading for all gears p,r,n,od,d,1,2,?

Originally Posted by clinebarger

DO NOT race the engine to WOT in park, The valves would float or you will picking up connecting rods of the ground! The following intructions are with the engine OFF.

You have a Lokar style TV cable, OK, I guess it has some kind of crimp for the cable end?

Adjust the jamb nuts to center.
Slide the plastic end clip down the cable, then the crimp.
Hook the plastic end clip to the carb.
Clamp some locking pliers on the end of the cable.
Rotate the throttle lever to WOT (have someone hold it there).
Using the pliers pull the cable tight.
While keeping the cable tight, Push the crimp against the plastic end & crimp it/tighten it.

After installing the crimp, With the carb still at WOT, pull the cable again, if there is slack, Adjust the cable housing toward the firewall a little at a time untill the slack is no longer present.

[clinebarger]

Originally Posted by Sick5

i have that part down.. thanks!
but when im doing the gauge reading with the car on the take the reading at WOT.. can i just pull on the cord to WOT and take the reading for all gears p,r,n,od,d,1,2,?

Your asking about the "dianostic line pressure test"? Yes, Just pull the cable.

This test is for DIAGNOTICS ONLY, Full TV pressures in reverse can reach over 300PSI. This should only be performed if there is a problem & for VERY short durations.

[67swb72klb]

would this presure chart apply to the 2004r too ?

[Sick5]

i thought you can use it to help adjust the tv cable as well.
i do notice that my 2nd gear shift to quickly
and i dont have a down shift at WOT

Originally Posted by clinebarger

Your asking about the "dianostic line pressure test"? Yes, Just pull the cable.

This test is for DIAGNOTICS ONLY, Full TV pressures in reverse can reach over 300PSI. This should only be performed if there is a problem & for VERY short durations.

[clinebarger]

Originally Posted by Sick5

i thought you can use it to help adjust the tv cable as well.
i do notice that my 2nd gear shift to quickly
and i dont have a down shift at WOT

Is the TV cable pulled all the way at WOT? The cable needs to be tight at WOT, Thats it on WOT adjustment.

What is the cable disconnected pressure? (closed throttle, Park)
What is the cable connected pressure? (closed throttle. Park)

Is your geometry is correct?

If closed throttle pressure is preloaded a few PSI & your TV Valve is buried at WOT, The TV system "should" be good,.....If you still have doubts......

Test #1. Detent test, From a stop, Take off very lightly/minimum throttle, As soon as it makes a 1-2 shift....floor the throttle, The trans should downshift back to first.

Test #2. With the engine running, warm, closed throttle, in park......Lightly press the TV cable wire HERE(arrow), The pressure gauge should react to the slightest downward pressure applied to the cable.

A governor calibration that is wrong for your final drive ratio will cause symptoms like your describing. http://www.summitracing.com/parts/TCI-326500/

[Sick5]

No.it.is not fully.adjusted and tighten at WOT. Reason being it won't shift under 2000 out of first.
Yes geometry correction is applyed to.the eldobrock carb.
Will make correction tomorrow.
Sorry for High jacking this thread...

[Sick5]

when shifting out of 1st gear rpm more than likely should be under 2k right