Dead Overdrive - '88 240 Automatic

  • Thread starter Thread starter Michael Cerkowski
  • Start date Start date
M

Michael Cerkowski

We were taking the car in for some routine service this evening. My
housemate was driving the Volvo. She felt the "power fluctuate" while
climbing a hill, saw a warning light "briefly flash", and pulled the car
over. When I drove it the rest of the way to the dealer, I discovered
that the O/D would engage only briefly when the throttle was off, then
it would immediate disengage again. The orange 'O/D off' arrow was *not*
lit unless I manually locked out the O/D. I asked the dealer to check
the relay and the kickdown cable (which I had visually inspected - it
didn't seem to be binding).

The report from the dealer was "it needs a new transmission". They
say the relay is working (it did seem to be working), the cable is ok,
and the O/D unit itself is broken. I did a Google search for this, and
only found one or two cases of this happening, with no responses from
the group. So, folks, what do you think? Would just a bad solenoid act
like this, or did the O/D unit die for no apparent reason? The car was
driven gently, the trans fluid flushed twice in 5 years, and there were
no previous problems with the AW-71 trans, aside from a leaking
tailshaft seal a few years ago. It was a very cold Winter, and the car
was whining in the coldest weather, but that whine went away at highway
speeds, and it seemed to be the carrier bearing.

Unless we can find a used transmission pronto, I plan to drive the
car with the
O/D locked out, and speed kept to no more than 60mph. Is the
transmission likely to hold together with a broken O/D? It seems to be
shifting fine in the other three gears. We don't want to sink a lot more
money into the car, but don't want to junk it, either. I'm actually
considering going with 195/75 tires as a cheap way to raise the overall
gearing enough to cruise at 60 without the engine roaring. Opinions?
Sources for good used AW-71 transmissions...?
--






http://www.albany.net/~mjc1/index.html
 
We're driving three 240's: '83, '86 and '89, all with automatic
transmissions. I've worked through a few problems with OD's.

Volvo OD's are very reliable, but the support electronics have various
places where they can fail, and I certainly wouldn't trust the first
mechanic who looked at it if they end up with a decision that you need
to do a huge job. The OD transmissions themselves don't fail very often.

It's possible (I believe) that a deteriorating (nearly broken) wire
between the gearshift box and the relay or OD solenoid could be causing
the failure. As I recall, the wiring runs from the thumb switch to a
relay located to the left of the glove box, and then back to the
hump-mounted shifter housing. From there it runs out through the box,
along the side of the transmission, to the OD solenoid. My wire had so
much wear in the shift box - from years of shift lever movement - and
also on the outside, along the side of the transmission, that it just
deteriorated. It worked intermittently and unreliably until it finally
just broke.

It's also common for the relay to fail, you often can get to it by
removing the glove box (about 8 screws visible when you open it's door).
It's to the left of the glove box, behind the center console. It's
easy to replace. The part is pretty inexpensive, unlike the
transmission-mounted solenoid which costs sume real money. But I
believe that if your OD light is working, that indicates the relay is OK.

If you're adventurous, check out the wiring and - if knowledgeable folks
say it could be dead, replace the relay. And definitely see a second
mechanic if it's still not right. Don't give yup on the transmission
itself, the problem is likely somewhere in the support electronics.

A mechanic friend of mine says you can permanemtly lock in the OD
function by re-engineering the solenoid. It still kicks in as usual,
and downshifts if you stop on the gas. You just can't lock out the
solenoid via the switch if you do the deed. It needs a hole to be
drilled inside the solenoid.

Bruce
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
To send email, remove all < > and [ ] and the junk ~ between:
[brucepick1]
< a~t >
[comcast.net]
 
Bruce said:
We're driving three 240's: '83, '86 and '89, all with automatic
transmissions. I've worked through a few problems with OD's.

Volvo OD's are very reliable, but the support electronics have various
places where they can fail, and I certainly wouldn't trust the first
mechanic who looked at it if they end up with a decision that you need
to do a huge job. The OD transmissions themselves don't fail very often.
Click to expand...

I was hoping that was the case. When they do fail, what are the symptoms?
It's possible (I believe) that a deteriorating (nearly broken) wire
between the gearshift box and the relay or OD solenoid could be causing
the failure. As I recall, the wiring runs from the thumb switch to a
relay located to the left of the glove box, and then back to the
hump-mounted shifter housing. From there it runs out through the box,
along the side of the transmission, to the OD solenoid. My wire had so
much wear in the shift box - from years of shift lever movement - and
also on the outside, along the side of the transmission, that it just
deteriorated. It worked intermittently and unreliably until it finally
just broke.

It's also common for the relay to fail, you often can get to it by
removing the glove box (about 8 screws visible when you open it's door).
It's to the left of the glove box, behind the center console. It's
easy to replace. The part is pretty inexpensive, unlike the
transmission-mounted solenoid which costs sume real money. But I
believe that if your OD light is working, that indicates the relay is OK.
Click to expand...

Yes, the light goes on and off with every single click of the switch, and
I can also hear the relay click. I think it's solenoid-related, or a dead O/D.
If you're adventurous, check out the wiring and - if knowledgeable folks
say it could be dead, replace the relay. And definitely see a second
mechanic if it's still not right. Don't give yup on the transmission
itself, the problem is likely somewhere in the support electronics.
Click to expand...

I did find a reference on the Net to the solenoid getting filled with
metal dust, and refusing to disengage. I wonder if this can also cause
it to not engage properly...?


A mechanic friend of mine says you can permanemtly lock in the OD
function by re-engineering the solenoid. It still kicks in as usual,
and downshifts if you stop on the gas. You just can't lock out the
solenoid via the switch if you do the deed. It needs a hole to be
drilled inside the solenoid.

Bruce
Click to expand...

Not interested in that. I do appreciate the response, though! How do I go
about
diagnosing the engagement solenoid? I actually plan to have another shop look
at
the wire to the transmission and the solenoid, but I would like to be able to
give
them explicit instructions. I'll check the wire in the shifter housing myself,
first, I
think.


++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
To send email, remove all < > and [ ] and the junk ~ between:
[brucepick1]
< a~t >
[comcast.net]

Michael said:
We were taking the car in for some routine service this evening. My
housemate was driving the Volvo. She felt the "power fluctuate" while
climbing a hill, saw a warning light "briefly flash", and pulled the car
over. When I drove it the rest of the way to the dealer, I discovered
that the O/D would engage only briefly when the throttle was off, then
it would immediate disengage again. The orange 'O/D off' arrow was *not*
lit unless I manually locked out the O/D. I asked the dealer to check
the relay and the kickdown cable (which I had visually inspected - it
didn't seem to be binding).

The report from the dealer was "it needs a new transmission". They
say the relay is working (it did seem to be working), the cable is ok,
and the O/D unit itself is broken. I did a Google search for this, and
only found one or two cases of this happening, with no responses from
the group. So, folks, what do you think? Would just a bad solenoid act
like this, or did the O/D unit die for no apparent reason? The car was
driven gently, the trans fluid flushed twice in 5 years, and there were
no previous problems with the AW-71 trans, aside from a leaking
tailshaft seal a few years ago. It was a very cold Winter, and the car
was whining in the coldest weather, but that whine went away at highway
speeds, and it seemed to be the carrier bearing.

Unless we can find a used transmission pronto, I plan to drive the
car with the
O/D locked out, and speed kept to no more than 60mph. Is the
transmission likely to hold together with a broken O/D? It seems to be
shifting fine in the other three gears. We don't want to sink a lot more
money into the car, but don't want to junk it, either. I'm actually
considering going with 195/75 tires as a cheap way to raise the overall
gearing enough to cruise at 60 without the engine roaring. Opinions?
Sources for good used AW-71 transmissions...?
--






http://www.albany.net/~mjc1/index.html
Click to expand...
Click to expand...




--






http://www.albany.net/~mjc1/index.html
 
When I drove it the rest of the way to the dealer, I discovered
that the O/D would engage only briefly when the throttle was off, then
it would immediate disengage again. The orange 'O/D off' arrow was *not*
lit unless I manually locked out the O/D.
Click to expand...

The dealer is correct!! If he replaces the trans, the OD will start working.
Of course he will have to fix what's really wrong to get you to pay for the
unnecessary transmission.

I had the same symptoms on my 86 240. If the OD light dosen't it is probibly
either the solenoid or the wires to it. TRY this:

* Run a fused line directly to the sol.
If it works fine it's the wiring.
If not it is the solenoid.

Overdrive (fourth gear) works when the sol picks up and lets oil flow. A
solenoid is an electro-magnet operated valve. The coils usually fail by
shorting out internally. These turn-to-turn shorts reduce the number of turns
in the coil and the magnet gets weaker. When the one on my 86 240 failed it
would work for a while, then drop out after it heated up.

OD Solenoids are expensive, $150.
I bought a "New" one from an unnamed Volvo dealer in West Palm Beach. The
package was opened and the "O" rings were missing, but it couldn't be a return
because they don't allow returns on electrical parts.
Well I was desperate so I took it anyway. It fixed the problem.

But when I took the old one out, I realized that I didn't need a new one. I
live in flat south Florida. I never turn OD off.
Next time I will
* Cut off and tape the wiring.
* Throw away the inner O ring.
* Cut (grind) a groove between the two holes
* And re-install the "repaired" solenoid.

That will bypass the solenoid and I'll have a 4 speed.

Do you ever take it out of overdrive?
If not, Bypass the solenoid and forget about it.

Al

Had
79 245 D,
81 240 D,
86 240 320,000mi and running fine when traded
94 944 Green 257,503 mi CRUNCH Parted out
Have
94 944 White 149,000 The New one
94 944 Maroon 135,000 mi
 
Vrparts said:
The dealer is correct!! If he replaces the trans, the OD will start working.
Of course he will have to fix what's really wrong to get you to pay for the
unnecessary transmission.

I had the same symptoms on my 86 240. If the OD light dosen't it is probibly
either the solenoid or the wires to it. TRY this: If the OD light dosen't it is
Click to expand...

I can't figure out your line " If the OD light dosen't it is ". Do you mean 'if

the O/D off light works ok, it's the solenoid or wiring'? Or that if it *doesn't*
light, it's the solenoid or wires...?
* Run a fused line directly to the sol.
If it works fine it's the wiring.
If not it is the solenoid.
Click to expand...

Is the dreaded Haynes manual going to show me which terminal I should
connect the hot wire to? I haven't dug it out of the (cold) garage, yet. That
does sound like a good way to test it, although I assume I should also
disconnect the wire from the relay, in case that wire is shorting? Otherwise
I'll just blow the fuse...
Overdrive (fourth gear) works when the sol picks up and lets oil flow. A
solenoid is an electro-magnet operated valve. The coils usually fail by
shorting out internally. These turn-to-turn shorts reduce the number of turns
in the coil and the magnet gets weaker. When the one on my 86 240 failed it
would work for a while, then drop out after it heated up.
Click to expand...

Thanks. I know what a solenoid is, but didn't know exactly how it engages
the O/D. I haven't actually tried it again - maybe I'll see if it works when cold.
OD Solenoids are expensive, $150.
I bought a "New" one from an unnamed Volvo dealer in West Palm Beach. The
package was opened and the "O" rings were missing, but it couldn't be a return
because they don't allow returns on electrical parts.
Well I was desperate so I took it anyway. It fixed the problem.

But when I took the old one out, I realized that I didn't need a new one. I
live in flat south Florida. I never turn OD off.
Next time I will
* Cut off and tape the wiring.
* Throw away the inner O ring.
* Cut (grind) a groove between the two holes
* And re-install the "repaired" solenoid.

That will bypass the solenoid and I'll have a 4 speed.

Do you ever take it out of overdrive?
If not, Bypass the solenoid and forget about it.

Al
Click to expand...

We do use it occasionally to descend a steep hill in Winter. The hill is
on most of the routes we take. Thanks for the ideas and explanations.
Had
79 245 D,
81 240 D,
86 240 320,000mi and running fine when traded
94 944 Green 257,503 mi CRUNCH Parted out
Have
94 944 White 149,000 The New one
94 944 Maroon 135,000 mi
Click to expand...




--






http://www.albany.net/~mjc1/index.html
 
You must log in or register to reply here.
Back
Top