FART_NUGGETS

Installed a new Daaco vette/s10 converter as well as a Transgo 700-2-3 kit.

Shifts good, 2-3 is weird once in a while but I'm hoping it's just settling in. Most of the time it's good.

Anyway, odd lockup issue. At cruise, say 50mph, the converter is not locked up. If I slowly apply throttle, at about 20% it locks up fine. If I back off to stop accelerating (but keep some throttle) it unlocks. Converter will not lock up under say 20% throttle, which is just about opposite of normal operation. I found this is related to TV pressure also:

If I adjust the TV cable temporarily to create more line pressure, it locks up and unlocks OK. Of course it shifts way too hard, and as soon as I floor it the cable resets to the proper position, so this is not a good solution.

I also have one of those springs that go on the TB end of the TV cable to give a little more early pull while still maxing out properly, It locks up OK with this additional amount of TV, but it shifts too hard for me with that spring in.

Seems like low TV is preventing converter lockup?

I searched, not finding much on this. Any ideas????

FART_NUGGETS

while installing the shift kit I removed and reinstalled the lockup solenoid, just to get the entire wiring harness out of the way. Could it have been damaged? Don't think it's possible to have resinstalled it wrong..... Removed and replaced the wire on the pressure switch also, pulled the entire harness out so it wouldn't be damaged.

I knew I should have drain-plugged the damn pan........

FART_NUGGETS

Dropped the pan, letting the VB drip for awhile. Nothing bad in the pan, fluid is still crystal clear and bright red.

Anything I could have screwed up on the kit to cause this? I triple checked every step, I don't think I missed anything, but something isn't right.

FART_NUGGETS

Me again, just talking to myself

If I have the TCC solenoid on the bench and I apply +12V to brown and "-" to black, should it click or anything? Because it doesn't. Bad solenoid?

skinny z

Yes. It should click but it's very faint in my experience. Hardly noticeable.
Put an ohmmeter across the leads and check for continuity. If there's an open circuit it's toast for sure.
That said, if you do get lockup on occasion, then the solenoid, by default, would be functional.
What else have you got in the circuit to the TCC? Vacuum switch? Brake switch?
There are also pressure switches and a temperature switch in the valve body. Where those altered or removed in the rebuild?

FART_NUGGETS

Thank you for the reply Skinny.

More info:

I read you can test the solenoid with air pressure. With no voltage applied, compressor set at 40psi, it passes air quickly as expected. When I apply voltage, the air flow slows down quite a bit, but it does not stop the air flow through the solenoid, a good amount of air still gets by. This kind of makes sense with my symptoms in my mind, where the solenoid is not fully closing, so it takes additional line pressure to get enough back pressure to apply the clutch properly? Should the solenoid be able to 100% stop 40PSI of air pressure?

Also, as far as sensors, this is a 1989, there is only one sensor in it, which I think is the 4th gear pressure sensor. The wiring in this trans is very simple, two wires go directly to the solenoid and the third pin on the case goes directly to the 4th gear pressure switch. The switch was not removed or otherwise disturbed during the shift kit install.

And as far as replacing the solenoid, anyone have a part number for this particular setup with ONLY a 4th gear switch? Everything I am finding online has plugs for things that don't exist in my transmission.

skinny z

Yes. Applying voltage to the solenoid should substantially limit the air passing through the valve.
As for the solenoid itself, I've had a half dozen of these transmissions apart and while I'm far from an expert, I could see no difference in their (solenoid) construction.
I also had only one switch in the valve body (4th gear) however in addition to that I also had an OEM vacuum switch that dropped the TCC on throttle apply.
A story I can relate: Perfectly functional transmission. TCC worked as expected. One day during a cruise, the lockup stopped working altogether. I suspected that the clutch in the TCI 10" converter had given up and sent it back to TCI for repair. As it turned out, the clutch was fine but there was some debris that was keeping the fluid path open and wasn't allowing the clutch to be applied. Something to think about perhaps?
As for the reply, at the very least it'll push your thread to the top where you might find a definitive answer.

FART_NUGGETS

So should I just buy the solenoid with the unnecessary plugs on it and just leave them hanging in the case?

Rockauto shows this for a 1989 5.0 Camaro. That second black plug is not needed in my transmission, only the plug that attaches to the case and the single blue clip that attaches to the 4th sensor. Would this be OK to leave that other black connector just hanging in there?

skinny z

It's difficult to say if that harness would work without actually seeing it or knowing the connections. What you need is continuity from the case connector through the solenoid and onto the blue 4th gear connector. The switch closes on 4th apply and completes the solenoid circuit. If that path is complete it would do no harm to have the additional connector unattached provided you can ensure it doesn't come into contact with any metal and closes the solenoid circuit when not wanted.

FART_NUGGETS

I appreciate the input, but that is not correct. 1989 has an ECM controlled TCC solenoid. The solenoid wires run directly from the case plug to the solenoid, and the 4th switch wire runs directly from the switch to the plug, and just tells the ECM when it's in 4th gear. They are not interconnected in this transmission.

FART_NUGGETS

Finally found a pic of the harness that is in my transmission, you can see the blue wire goes direct from the 4th pressure switch to the case. This web site refers to it as a "Type 9".

skinny z

I should have caught on to the ECM control when you described having no additional switches (vacuum) in the circuit. Strictly old school here having removed the computer and hard wiring all of the controls.
Are you able to locate / purchase the solenoid in the 2nd picture?

FART_NUGGETS

Only one place so far, Bowler Transmissions, which is where I found the photo. $30 + $18 shipping...

skinny z

I found a good source for miscellaneous parts is a transmission shop. It may be that a local rebuilder could have a bucket of solenoids sitting in a corner somewhere.

FART_NUGGETS

Grabbed a splice-in solenoid from Amazon, will be here tomorrow I am hoping this is all the problem is. Found a video of a guy bench testing solenoids online, and mine sounds just like the one he states is "bad", just hisses less when it's turned on. The ones he tests that are "good" make a nice 'thunk" and completely stop the air flow, which mine definitely does not.

skinny z

Good luck.

FART_NUGGETS

New solenoid fixed the lockup.

Bad news, took a 20 or 30 mile drive around today and the 2-3 shift got much worse, low, part and full throttle. Transmission when in OD also shifts very early at WOT, at like 3000-3500 1-2 and 2-3. By the end of the drive, 4th was basically useless, any throttle at all would slip the transmission, and 3rd gear was only good for cruise, anything over about 20% throttle slips. Transmission has 80k on it and I am guessing I did something wrong, or perhaps there were issues with it already that the previous owner covered up with the vette servo and the lack of filter. I give up. Probably going to shop around for either a local rebuild or a reman off the internet. Super bummed. That's what I get for messing with it. Should have left it alone.

skinny z

Could be the previous owner had the TV adjustment messed up and basically cooked the clutches. And I can't see it working at all with no filter.
Somewhat similarly, I picked up a used low mile transmission, whose owner seemed believable enough and after about a half dozen miles there were no forward gears left. I blame myself for that as I put in a stall converter from a previous transmission that had failed. I didn't think that the converter itself would be full of crap and eventually spread through the trans.
Live and learn.
As for a replacement there are plenty of heavy duty upgrades for the TH700 along with the shift kit you've installed. It depends on what level of durability you're after. A race orientated rebuilder might give you better results that the shop that caters more to the grocery getter.
Sorry about your luck. I feel for ya.

FART_NUGGETS

I put about 2000 miles on the car since I bought it in September 2017, and it ran and shifted fine the whole time without a filter. I am assuming the transmission was overfilled to get fluid to the height of the pickup hole. I don't think I had ever checked it honestly. I will choose to believe that it was band-aided together to get the car sold and it wasn't something I did....

My father in law is a retired master transmission tech, spent 20 years or so doing rebuilds at Aamco. He said he'll walk me through rebuilding it, and got me his discount on a full street/strip kit for the 700, HD clutches, new sun shell, etc. Picking up parts on Monday and bringing the unit up to his house next Sat to rebuild it. Looking forward to learning some new stuff

Pulled the trans back out yesterday, I'm getting good at it, start to finish from putting the car on ramps to washing my hands at the end was 90 minutes. Hopefully it goes back in easy.

Of course now that the trans is out, and I have some down time, I keep looking at that $1800 L31 Vortec on Jegs.....................

Fast355

iTrader: (2)

DO IT!!!!

FART_NUGGETS

I like you people......

skinny z

My TH700 build sheet.
I went about as far as I thought reasonable stopping short of input and output shafts. Equivalent to a Gear Star Level 4 by my estimation.

Although I've rebuilt transmissions before (and long before) I wasn't about to do this one myself. Had I had a mentor like you have, that may have been different. I'd be curious as to your father-in-law's opinion.
Good luck and keep us posted.

FART_NUGGETS

Awesome list, I saved it

Spent a very nice Monday afternoon putting the 700 back together.

Rebuilt the pump, all new HD clutches and black steels, all new seals, new HD band, and new HD sun shell. Everything else was in good shape so we left it alone (sprags, drums, etc). made up a few new obscenities while trying to reinstall some of the little snap rings, but she went together nice and the father in law said everything looked good, just had a badly burned set of 3/4 clutches. I did have a 2/4 servo snap ring incident at one point recently, at full throttle at about 50mph the ring popped loose and the servo came about 1/2 way out (ring stayed partially seated and kept things attached to the case) from which I limped back home about 2 miles while spewing fluid, so that definitely could have had something to do with it failing now, as well as who knows what in the previous 80k miles before I owned it. The no filter thing really throws everyone I tell about it for a loop........

Got it bolted back up in the car last night, but didn't have time to finish the driveshaft, x-member or torque arm. Hopefully pull off a gentle test drive tonight.

Fast355

iTrader: (2)

LOL @ the snap ring comment. That output shaft snap ring right in the middle of the planetary set is fun isn't it???

FART_NUGGETS

Yeah that was definitely the worst one.

skinny z

Which helps to explain my reasoning for having someone else do the build this time around...
Glad to hear you're making progress.

FART_NUGGETS

Got it finished up last night, have put 50 miles on it. So far so good Nice quick shifts. No leaks. No odd noises. Hopefully that's enough transmission work for a while, I really hate to R/R the thing on jack stands in the garage, and I did it twice for this fiasco. Hopefully it's good for a long time now

But then again, $250 to do all the work myself vs. $1200-$1600 at a local shop, I'll just take some extra motrin and call it good. That's $1000 more left for other stuff

FART_NUGGETS

I would like to get another 500 usable RPM out of this motor on the cheap.... it shifts at just at or over 5k, but she's running out of steam at that point so it almost feels like I need to let off a bit to get it to shift, but it shifts. that extra second or two seems like an eternity at 5000r WOT.

skinny z

That's always a bonus. I was lucky (or well aquainted enough to have my rebuilder tack on only an extra 500 bucks for the rebuild of parts posted earlier.) That stuff rarely happens.

That would be a governor issue. There are several posts here that address that. Resist the temptation to "adjust" the TV cable to compensate.
Do a forum search on governor in the title.

Like this one!!
https://www.thirdgen.org/forums/tran...ent-700r4.html