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brooksman9

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Nick,
Didn't want to highjack the other thread but hoped you might answer a couple of questions regarding TV cable setup and the pressure testing mentioned in the other thread. Back story is I bought this 86 K10 from a guy I was working with a few months ago. He only had it for awhile and decided to get rid of it. When he got it he said it had an intake leak. He replaced the stock GM intake and Q-Jet with an Edelbrock intake and an AVS Carb. I had to finish the install and get it all running. No big deal.
The more I read about TV cables I wasn't sure I had it set right. From what I had read to set you push the tab in, slide the sleeve back release tab and floor the accelerator cable. It did not ratchet out as I had read but stayed retracted. It did extend though if I held the button in and had someone floor the gas pedal. Pic is how it is set now. Also had to purchase the adaptor for the TV cable for the accelerator bracket. It does shift around 15-20 mph 1st to 2nd. Can't really tell about 3rd. It is either not moving fast enough or too soft for me to feel. I have only driven around the block a couple of times. I have been working on several other things with the steering so slowly getting around to this part.

1) Does the setting look about right? I know the distance difference from the Q-jet to the AVS is about 3/4" less.
2) Watched a few pressure testing videos on Youtube. Do you think a HF pressure gauge is good enough? About $30-40. Summit is around $60.
3) Attachment port driver side of transmission above linkage?
4) What is pressure at stall? In gear and giving gas to RPM of stall converter? Sounds kind of risky to me. lol
5) Thanks.

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NickTransmissions

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Hi Patrick,

The cable should be tight when adjusted correctly however the only way to know for sure is to hook up a gauge. The HF gauge should work though I'd spring for a Snap on, Mac, Matco, etc but if HF warranties their gauges, you can bring it back if it fails on you.

Not sure if you have read these instructions before but they're the best I have seen out there on the net and provide physical and/or link to all my 700R4 customers. They will give you all the direction and guidance you need as well as provide a chart with the correct pressure ranges for each 'range' setting (P,R,N,D,D3, 2,1) for you to refer to when doing the pressure test. Remove the pressure port tab on the driver's side of the trans just behind the bell housing with a ratchet and 7/16" socket or wrench and thread your gauge into that port.

"Stall testing" while on the ground is somewhat risky and shouldn't be done more than once or twice, if at all. What most folks will do is take pressure readings at idle and if those readings are within acceptable limits, they will leave the gauge in the trans and take it out on the road for a quick test drive, watching the gauge as they drive around. The main thing is to ensure you have immediate, robust line pressure rise once you begin to accelerate.

Additionally, you should feel the transmission shifting gears. The 1-2 shift will be a bit more noticeable than the 2-3, 3-4 and TCC lock up however you should still feel the latter two as well as the converter clutch applying at around 40-45 mph or so, cruising with minimal load on the engine (i.e. just enough to maintain your speed).

Test prep
Make sure your TV cable is in serviceable condition - if you have any doubts, simply replace it as they are not that expensive for a basic stock replacement cable. Lokar makes some fancier ones for a little more money, I believe. Otherwise, simply make sure you're on level ground and that fluid is all topped off and reading full hot as you should have the vehicle at operating temp before beginning the test.

Test & Results @ Idle
Pressures should be 55PSI-75PSI in P,N,D,D3 at idle and 90 PSI for R. You should have full pressure 160-180 PSI for 2 and 1.

If you have insufficient pressures at idle, your first step is to play with the cable adjustment to see if you can bring them up into the required ranges. If that fails to elevate / stabilize pressures, then re-examine your geometry. If your line pressures at too high (i.e. 100+ PSI in P,N,D,D3 at idle) AND the 5/16" TV exhaust check ball has been installed in the transmission, that would indicate your adjustment is incorrect and main line pressure is insufficient, causing that check to seat. This check ball is basically a fail-safe measure to protect the transmission in the event of TV cable failure that GM began installing in L1984 or 1985. If no 5/16" check ball is installed but pressures are way too high anyway, it's likely the main TV valve in the valve body is stuck in the bore (can also be the case even if the check ball is present).

If line pressures are erratic, sometimes low, sometimes high but never stabilize, your first step is to suspect the TV valve in the valve body is sticking and/or the TV valve bore is excessively worn. If so, you will need to replace the valve body or ream the TV bore with the Sonnax reamer tool kit and install their oversized TV valve and spring kit. If that doesn't fix the problem, then trans will have to come out and pump removed, disassembled and inspected for wear (at that point, your rebuilding the transmission unless it has just recently been overhauled).

Road Test
You should see at minimum a 50% increase in line pressure immediately upon accelerating in first gear on your way to shift to 2nd. Then once at stall, your pressures should largely max out in Drive. There's no real need to road test in reverse unless you want to. Reverse engagement should be fairly robust (earlier, pre-auxiliary valve body units will have harsher engagements then the 700R4s with aux valve bodies).

If you do not see immediate line pressure rise to acceptable levels, stop immediately and park it. Otherwise, you'll do damage to the clutch packs (particularly the 3-4) if you try to drive and accelerate even moderately...I've seen these transmissions burn up in as little as a couple miles of driving where the TV cable wasn't hooked up or was poorly set up and adjusted.

Hope the above helps, perhaps others will chime in as well with their thoughts and experiences or tips/tricks/things to keep in mind.
 

brooksman9

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Nick,
Thank you for your time and sharing your knowledge. I have seen those instructions before you linked to. Only thing that threw me off was the part where it did not ratchet on and self adjust. I did read somewhere about some cables that did not do that. Not sure if that information is correct or not though. I will pick up a pressure gauge set see what I have before driving any more. Waiting on a lift kit at the moment and needing to hook up a tach I got so I have time to spare. Thanks again.
 

brooksman9

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Nick. This is what I am seeing so far. No real rise in pressure as accelerating but just stomping a little in about a 25' section of driveway. Anything stick out?
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brooksman9

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Lowered idle speed a little
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brooksman9

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I did slide the cable housing back, safer direction, until almost all the slack was out of the cable. You can see slack in the pick above. No really difference in the pressures though.
 

NickTransmissions

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Nick,
Thank you for your time and sharing your knowledge. I have seen those instructions before you linked to. Only thing that threw me off was the part where it did not ratchet on and self adjust. I did read somewhere about some cables that did not do that. Not sure if that information is correct or not though. I will pick up a pressure gauge set see what I have before driving any more. Waiting on a lift kit at the moment and needing to hook up a tach I got so I have time to spare. Thanks again.
You're welcome, man. Your idle pressures look good (manual low and 2 are a tad low but ive seen them on the low side before without adversely impacting transmission health and function. Take it on a short road test to see if you get any line rise at all - dont floor or get on it too much. If you dont see any line pressure increase at all, turn around and get it back to the shop for more trouble shooting.
 
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brooksman9

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Well, drove around the block with the TV cable basically all the way retracted. No pressure rise and di not shift out of first. Reset the cable by pushing the button in and having my wife step on the gas pedal all the way to the floor. Still no pressure rise and didn't shift. What is my next step?
 

NickTransmissions

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Well, drove around the block with the TV cable basically all the way retracted. No pressure rise and di not shift out of first. Reset the cable by pushing the button in and having my wife step on the gas pedal all the way to the floor. Still no pressure rise and didn't shift. What is my next step?
Your TV plunger and sleeve may be worn...I'm dealing with the same issue for one of my 700s (good line pressure at idle but no line rise).

You can:
1. Try a diff valve body
2. Install Sonnax's 700R4 TV sleeve and plunger kit (77966-94K) or their hp sleeve and plunger kit (77966-94MK). The latter kit eliminates part-throttle sleeve orifice which prevents a forced 4-3 kick-down below three-quarter throttle

If you try swapping and the plunger/sleeve kit and still not working (assuming the cable is serviceable, geometry and adjustment are correct) then it's a pump problem which could include excessively worn PR valve/valve bore, boost valve worn or defective), excessive clearance between rotor/slide and deck surfaces. May also be as simple as a clogged filter but not likely, esp if the filter has been recently replaced.
 

brooksman9

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Thanks Nick. Bought the truck knowing the tranny had been rebuilt and has a non lock up converter in it but that's about all I know about it. I will drop the pan an do a little inspection later this week. Just started back to work on my 12 hour night shift Sun-Wed. Saw this video on youtube and will compare to where things sit and setup before reinstalling pan. Any good recommendations on a filter/gasket kit?

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Well, drove around the block with the TV cable basically all the way retracted. No pressure rise and di not shift out of first. Reset the cable by pushing the button in and having my wife step on the gas pedal all the way to the floor. Still no pressure rise and didn't shift. What is my next step?
Hey Patrick, I have been following along since the beginning of the thread because I have the same trans and not confident it was setup correctly with the carb. I haven't driven it much yet.
I am confused about the quoted post above. Wasn't your trans shifting into second at 15-20mph a week ago (post #1)?
What changed?
 

brooksman9

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I believe it was. Not all that sure now. It did feel like it but the trips have been very short and just in the neighborhood.
 

brooksman9

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Hey Nick. If I am correct on proper adjustment of the TV cable the arm should be touching the plunger at idle correct? Below is what I found when dropped the pan. The plunger is back just a hair. Maybe a 1/4" i assume fluid keeps pressure on it when running? Thanks.
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brooksman9

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So with the sleeve completely retracted I am still about 3/16" from touching the plunger. I am going to get one of these adjustable brackets to see if I can get closer to proper adjustment. I assume the difference between the original factory intake/Q-jet and the new Edelbrock with AVS is the cause of the issues.

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