700r4 valve body problems?

[Rocky]

I just rebuilt my 1986 700r4 tranny. I replaced every questionable
part excluding the valve body. Prior to the rebuild the tranny would
sometimes start off in second gear. After the rebuild, it acts the
same. I replaced both sprags and double checked for proper locking
direction. I also verified that the input and output shafts had the
proper amount of end-play. Are there possible problems with the valve
body that could cause this to occur? What if one of the valve springs
broke? Are there seals in the valve body?

Thanks for the help.

Rocky

[George]

Most intermittent trans problems are valve related. Mechanical problems
are usually there all the time. Did you disassemble the governor and
make sure the valves move freely. Post the vehicle type and I will look
up the transmission in my Mitchell on Demand for Transmissions for a
possible diagnosis and a look at the valve body.
Good luck, George

remove second 5 to e-mail

[Loren Knighton]

Thanks for the help.

Rocky

Rocky:

Three things come to mind. Sticky governor valve. Stuck 1-2 shift valve in the
valvebody. Forward clutch sprag installed ass backwards. Good luck to you.

Respectifully submitted,

Loren Knighton
Woodland, CA.
IATN, TRNI
Under the hood since 1964

[bobby]

I had a similar problem after a rebuild on a Ford FMX transmission several years
ago. Took it back to the rebuild shop and they said they replaced the valve body
and it shifted normally after that. The little bit of reading I could find
mentioned that grit will cause the valves to hang and drag. The recommended fix
was to clean the valve body and then install the valve plungers and slam it on the
wooden bench several times on each side to imbed the grit particles into the soft
aluminum valve body. Hummmm.. The shop I went to said they got one out of the
salvage yard.....

bb

[THP]

did you R/R all the check valves and check to make sure that there were no scars
on the valve body, or on any of the parts for that matter - a small scratch in
the system may cause a multitude of problems - if it's shifting improperly -
valve body has a problem. if it slips - it's worn out discs -- you people need
to diagnose the problem before you fix the problem!

this group is full of backyard techs that just R/R in the hopes that the problem
might fix itself - example: your daughter has a nose bleed - what do you do? you
put her leg in a cast in the hope that her nose bleed will cease!!!! cept her
nose is still bleeding.......

THP

--
If it ain't broke, why fix it!?
"Loren Knighton" <backn...@aol.comno1spam> wrote in message
news:20020515030901...@mb-fq.aol.com...

[John Kunkel]

"Rocky" <we...@iceinc.ws> wrote in message
news:b0183f05.0205...@posting.google.com...

Did you disassemble the valve body and clean the parts as part of the
overhaul? If not, the 1-2 shift valve could be stiff in its bore and
sticking intermittently.
The valve body should be completely disassembled and cleaned during the
overhaul and the individual components therein inspected for condition and
the valves for smooth operation in their bores.
John

[Rocky]

"THP" <spamno...@attbi.com> wrote in message news:<KGvE8.73639$071.27...@typhoon1.we.ipsvc.net>...

The thing the I most appreciate is that everyone has their own
opinion. When I ask for help, I do so because I need ideas to spark my
own thought process. I never blindly do things that people advise.
Rather I run the opinions through my internal logic filter. The
consensus has been that the problem is most likely in the valve body
or the governor since the problem is intermittent. I thank everyone
for their help. Now I will focus my troubleshooting attention in those
areas.

Rocky

[Loren Knighton]

>The thing the I most appreciate is that everyone has their own
>opinion. When I ask for help, I do so because I need ideas to spark my
>own thought process. I never blindly do things that people advise.
>Rather I run the opinions through my internal logic filter. The
>consensus has been that the problem is most likely in the valve body
>or the governor since the problem is intermittent. I thank everyone
>for their help. Now I will focus my troubleshooting attention in those
>areas.
>
>Rocky

Say Rocky:

When you git this beast sorted out-kindly let us know what worked for you.
Thanks.

[corva...@gmail.com]

My '84 Suburban 6.2 diesel 700R4 4 speed OD was shifting fine, tho never had lockup, then on a trip back from Michigan to Adirondacks (2000 miles total), it quit shifting a couple hundred miles from home. It would only shift at way too hi an engine speed, and I tried rocking shifter, stabbing gas pedal, lengetnthing TV cable etc... After 100 terrible miles, finally in 3rd at 40mph, I took an exit to visit some friends that build '32 Fords, and all of sudden it's back to normal!

All was fine for 2 weeks until I jabbed the throttle to junp accorss and intersection, and it's back to thinking I'm flooring it! I dropped the valve body, and removed a few valves, but they're a real bear to remove, and I thot I would do more harm, so I stopped. TV valve seems to move fine. I cleaned everything thoroughtly, and re-assembled, also checked governor, and it's the same. I replaced gov with another one, same, lengethend the TV cable, and same, but now it's hanging in 2nd unless I floor it, then the shift is way late. The pan had zero paper or brass, so I know the tranny is fine. It prolly has 80k.

I need the truck for work, but I basically drive around town in 1st gear, with the occasional shift to 2nd. At 40 it will hit 3rd, but drop back to 2nd at 35. I double checked the TV cable, and changed back to my old gov, and jacked up rear wheels to make sure it's spinning, all is normal. Any thoughts?

[Steve W.]

corva...@gmail.com wrote:
> My '84 Suburban 6.2 diesel 700R4 4 speed OD was shifting fine, tho
never had lockup, then on a trip back from Michigan to Adirondacks (2000
miles total), it quit shifting a couple hundred miles from home. It
would only shift at way too hi an engine speed, and I tried rocking
shifter, stabbing gas pedal, lengetnthing TV cable etc... After 100
terrible miles, finally in 3rd at 40mph, I took an exit to visit some
friends that build '32 Fords, and all of sudden it's back to normal!
>
> All was fine for 2 weeks until I jabbed the throttle to junp accorss
> and intersection, and it's back to thinking I'm flooring it! I
> dropped the valve body, and removed a few valves, but they're a real
> bear to remove, and I thot I would do more harm, so I stopped. TV
> valve seems to move fine. I cleaned everything thoroughtly, and
> re-assembled, also checked governor, and it's the same. I replaced
> gov with another one, same, lengethend the TV cable, and same, but
> now it's hanging in 2nd unless I floor it, then the shift is way
> late. The pan had zero paper or brass, so I know the tranny is fine.
> It prolly has 80k.
>
> I need the truck for work, but I basically drive around town in 1st
> gear, with the occasional shift to 2nd. At 40 it will hit 3rd, but
> drop back to 2nd at 35. I double checked the TV cable, and changed
> back to my old gov, and jacked up rear wheels to make sure it's
> spinning, all is normal. Any thoughts?

Sounds like a classic bad governor. They get sticky and start hanging up
at various spots. Causes different shift points depending on where they
stick. The sudden changes in shift points and the sudden change when you
stabbed the throttle all point that way. Be sure to use a diesel
governor as they are set up different due to the lower rpm band.

Reset the TV cable as well as those being out of adjustment do bad
things to the 700R4s.

The lack of lock-up could also be causing problems. Being an 84 that
trans is likely one of the 27 spline units, they have a few odd issues
if the lock-up isn't working. Lots of info on that online.


--
Steve W.