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sweeper
22-08-2010, 10:09 PM
I have search the forums and cannot find a similar problem or solution to my issue.
The issue is, when selecting reverse the car moves but it sounds like the parking pawl/mechanism is still trying to engage. Going into Drive, 1st 2nd etc.. is fine, no noise and all drive. I have been quoted $600 for a reco box and fit to $1700+. The only other avenue I can think of is, if the selector cable is out of adjustment will this cause the "miss selection" of the 'box and try to engage reverse before the parking mechanism is disengaged? If this is so, has anybody got any specs/how-to's to adjust the cable?

Your help will be much appreciated.

Bob

tn sedan auto
tp 5 speed manual wagon

Crumb
23-08-2010, 12:26 AM
Hi Bob

It’s been a while since I did this but I’m pretty sure it’s something like this,

Engine off, car in park, handbrake up and chock the wheels.

The selector cable connects to the neutral safety switch on the gear box, it will have a black boot on it and a nut on each side of where it joins on to a lever that is bolted onto the safety switch.

Disconnect both nuts for the selector cable and pull it out, At the other end of the lever there should be a hole, turn the lever anti clockwise towards the indent on the switch, as you do this there should be two clicks (from park to reverse and from reverse to neutral)

The hole on the selector lever should line up with the indent on the switch (stick a drill bit or something in there to check) if it doesn’t line up, loosen the nut that holds the lever onto the neutral safety switch and turn it until it does line up.

From inside the car stick the shifter into neutral then reconnect the selector cable and the nuts that hold it there back on and tighten them whilst making sure you don’t move the lever out of alignment with the switch indent (keeping the drill bit in the hole and indent might help)

Check to make sure the car doesn’t start in reverse or drive after this, hold down the brake hard just in case it does:eek2:

I had to do this to my TP when I got it as it wouldn’t always go into drive or reverse straight away. For me the alignment hole lined up with the indent but the cable was out, doing the above fixed it.

Good luck

magna buff
23-08-2010, 06:59 AM
this is it

also the cable itself has an adjustment near the gearbox
check the front and rear engine mounts are sound

see how the drill bit is used to line up neutral holes

http://i253.photobucket.com/albums/hh59/magnabuff/line_up_647.jpg

sweeper
27-08-2010, 12:36 PM
Thanks I'll give that a go

magna buff
27-08-2010, 02:00 PM
it has to be something simple

a reverse failure is so rare

as you have forward gears the box should be ok internally

sweeper
17-09-2010, 04:33 AM
Hopefully this weekend or the next will give us a chance to work on it. The guy needs this car as he has no job and a disabled child to get around to varius doctors and specialists. So here's hoping it is a simple fix. I'l keep people upto date. Thanks again

magna buff
17-09-2010, 10:27 AM
checking the repair manual
I can eliminate torque converter and oil pump because it drives ok
fluid level
(to check hot... cycle all gears then in park check with motor running
level has to be between both lines on the dipstick)

sweeper
19-09-2010, 12:55 PM
Ok guys, (1) checked fluid, foaming! can't be too high, hasn't put any fluid in for a year.
(2) , linkage at the box was adjusted, now is central in the lever when in neutral.
(3) the interesting one. When the box is in neutral the box is still locked in park, or the park pawl is engaged. if you rock the car back and forth, you can feel the park mechanism disengage. Put in drive and away we go.
Back to neutral the park mechanism again engages, gentle rock and voila disengages. put in reverse the park mechanism re-engages again, or tries to and the car ratchets away in reverse.

Any Ideas as the haynes manual (i found it buried!) doesn't really do much for me.

Thanks again for any help or a elcheapo 'box for sale in Adelaide would be much appreciated :)
Thanks again

magna buff
19-09-2010, 03:38 PM
ok thats good news you have reverse
its just this pawl thingy

you will need a pan gasket and filter
to drain the box there is a 17 mm nut
around near the diff part on the drivers side
you drain the oil that way
then take the pan off

with the pan off you should be able to
see the parking pawl ...beside the valve box
by the picture I have
the pawl is held in place by a ball bearing and a spring
http://i253.photobucket.com/albums/hh59/magnabuff/pawl.jpg
you may be able to correct the pawl problem that way

only a guess
the actual metal shaft of that pawl
runs through the inhibitor switch
if at some time that shaft may have slipped and let the ball bearing out
only leaving a bent spring to hold it in place

sweeper
20-09-2010, 12:42 PM
Thanks, looks like another weekend diy is in order!

All of your help is appreciated.

I'll keep the thread posted on developments.

magna buff
20-09-2010, 03:51 PM
the tranny uses mitsubishi tranny oil only
and 4 liters is about what the pan and diff holds
I use a length of garden hose and a funnel
to refill through the dip stick hole

when the pan is off you will need a helper
to move the selector so you can watch the pawls action
watch out for dripping tranny oil
if the valve body has to be taken off to fix the pawl problem
there is a sequence of only a few screws to be undone
so the valve body remains intact
http://i253.photobucket.com/albums/hh59/magnabuff/auto.jpg

magna buff
21-09-2010, 11:20 AM
just took the pan off my TN auto
http://i253.photobucket.com/albums/hh59/magnabuff/100_0883.jpg

if the pawl keeper ball bearing is the problem

the valve body does have to be undone
there isnt room to pull the pawl and rod out
so follow the sequence of bolts in previous post
******
use a clean tarp or sheet on the ground when removing the valve box
has to be a clean dust free area under the car

on top of the whole valve box is an 0 ring
that has to be held in place with vasaline so it is in the right position
if it isnt you wont have any oil pressure in the box

magna buff
24-09-2010, 06:58 PM
the picture of the park sprag (in auto repair manual )

looks like it has a large coil spring on its pivot pin

it runs off the smaller internal selector shaft attaches to the pawl

the internal selector has a cam and a spring for the park sprag

need to check that also
http://i253.photobucket.com/albums/hh59/magnabuff/sprag.jpg

sweeper
25-09-2010, 08:13 PM
This is gonna be good!. Here's hoping that all works well.

sweeper
25-09-2010, 08:16 PM
Any torque values for the valve body bolts and the pan bolts?

magna buff
26-09-2010, 09:14 AM
4-6 nm for all valve body bolts
10 nm with caution on a cork gasket for the pan bolts

5 nm oil filter bolt

sweeper
27-09-2010, 09:24 AM
thanks

magna buff
06-10-2010, 03:42 PM
Now I and have to drop the valve box myself
on my wagon
the soleniods have stuffed up on me

got no reverse and only 2 gears
so off with the pan:nuts:

oh what fun
did you solve the problem on yours sweeper

sweeper
09-10-2010, 01:23 PM
Well here is the latest installment. Solved the parking pawl issue. The problem was that the cone/cam(?) was not restrained from going forward, therefore when ever you got close to neutral the spring pressure was enough to force the cam up to activate the parking mechanism. The restraining mechanism was a crimped section of the rod that had worn away. Solved that by removing the cone assembly well forward of the mounting bracket, keeping it out of the way. Now we have no drive in any gear! What I surmise is that I have broken a wire(s) from the connector to the valve body when the valve body was removed. I have torqued up the valve body, new filter etc and 5 liters of auto fluid. If I look into the pan through the dipstick hole I can see the fluid bubbling gently. If I take off the return lines to the transmission cooler, fluid does come out, more like dribbles out, not flow. I didn't drain the torque converter as I got about 5 litres out of it.

So, the question is, can I obtain a wiring diagram to the auto so I can trace the wires etc. and see if a broken wire is the cause, or at least a pin out with voltages/resistances so I can track down this issue.

Now I know why I like manual transmissions!

Thanks for your help in the past and for any more help unitl I cry uncle and shoot the thing, or get another box.

Bob

magna buff
09-10-2010, 01:42 PM
Did you refit the 0 ring
at the top of the valve body..... I mentioned it

it is in this picture almost centre

dont know if the lack of drive is electrical

there should be 4 wires coming out of the box
the 4 solenoids

grey red orange yellow
http://i253.photobucket.com/albums/hh59/magnabuff/valve_body.jpg

sweeper
10-10-2010, 11:36 AM
yep the oring didn't move, (I hope!) so I'll probally drop the pan etc.. next weekend and get a multimeter onto the wiring to check it out. I reckon I've have broken a wire because I know that in the process of dropping the valve body I couldnt get the connector out of the transmission case. So I may have stretched a wire or twisted it off. Another oily weekend coming up!

magna buff
10-10-2010, 03:25 PM
12 volt current test
dont have to remove pan to test wiring

Unplug the outer tranny wire plug

At the box round plug in
goes around like this

2 1 ......facing you
4 3

from the repair manual

resistance for solenoids is 3 ohms at 20 degrees (resistance varies with temp)

Apply 12 volts between " 3" positive and the tranny(earth)
you should hear the soleniod click

I run a wire from the + terminal of the battery to the pin outs

do the same to each solenoid 1 2 4 etc

if no click thats your broken wire

sweeper
12-10-2010, 09:18 AM
thanks, that sounds like a plan.

Still gunna be oily if that wire is broken :)

magna buff
15-10-2010, 05:19 PM
at the plug for the solenoids

there is a u shaped retaining clip on the inside of the box

holding that plug in place...its very small

only just saw it in an exploded view of the TN auto today

sweeper
16-10-2010, 11:08 AM
excellent info! that will be a great help when i tackle it

sweeper
28-10-2010, 01:30 PM
Problem solved Boss!. My bad! Dropped the pan, filter & valve body. Checked the wiring, all good. Ok, checked the "O" ring, looks good, but replaced any way. $18.00 from SuperCheap (!) freebie from Sprint auto parts :) reassemble, hang on whats this spool valve doing sitting in my hand? ok it goes into the side of the valve body but where does it connect to? The light turns on and the hamsters happy! the rod that descend from the selector shaft engages the cutout in the end. That's what I missed when I reassembled the first time. reassemble again, all gears working.

We are now happy. One magna down, one to go. Now my Magna the cv joints have just shit themselves. another dirty weekend coming up!

Thanks for all the help.