apparently the od has not engaged in sometime and driven like this around town with minimal highway speeds.

the transmission shifts perfectly in every other gear up and down. fluid was brown and old smelling and has been thoroughly flushed.

bypass plate installed.

no od.

kickddown cable not binding, retracts smoothly.

thoughts?

od was obstensibly not engaging because of broken white wire next to the shifter assembly.

i removed the old solenoid in which i had cut a slot with a dremel

the slot width was one cutting wheel in thickness

i widened the slot to 3 thickness's in width and reinstalled.

upon reaching 38-40 at light pedal the transmission shifted into OD effortlessly.

conclusions:

if you make your own bypass plate using the old solenoid make sure you make the slot wide enough to allow sufficient fluid to pass through to generate the needed fluid pressure.

to skinny a slot makes it impossible to obtain the needed fluid pressure to up shift into OD

Hi,

I crossed over a couple years ago to my first automatic and not experienced this overdrive issue as of yet.
I need to ask a few questions.

What goes wrong with the solenoid that stops it from passing enough fluid in the first place?
Electrical or crud. Does the coil burn out?

On my M46's I had one stop up and I just cycled it while washed it with cleaner to make it work again.
Is the automatic solenoid different in some way? Does it work backwards or something?

Is it true that If you install a bypass plate or cutting a groove into the solenoid body, would I be correct to say, that you now have no way to lock out the operation of the overdrive?

Does it ruin the solenoid to ever returning it to locking it out ever again?

What do you have to do drive up a long steep grade? Get in the slow lane or let it hum or scream and let it keep shifting.

I can't say it's a fix to do away with that option, but that's me.

Fill me in a little please.
Phil (:-)

normally the wire to the solenoid breaks. sometimes the solenoid itself get water into it from rust and degradation of the rubber material which surround the wire going into it.

yes, once the solenoid groove is cut there is no going back to using that solenoid for od lockout

driving up a long steep grade i have not found the od solenoid to be relevant. once the engine slows down from grade the speed reduction will automatically kickdown the transmission into 3rd as if you stepped on the gas and used the kickdown cable to do the same thing.

imo the solenoids real function would be if you were towing something and needed to REMAIN in 3rd gear for a specific duration of time.....like going up a steep grade. and did not want the transmission to be going in out of od as you hovered in the 38-44 mph range.

doing what i have done in no way prevent anyone from buying a new solenoid, fixing the wire if thats the cause and regaining full use of the shifter lockout to od fucntion.

i think this by pass started a while ago when cheap after market solenoids were unavailable and the owwer was face with a part costing hundreds for a function they did not use.

its really a function of how often a driver expects to use that function. i know of long time 240'ers who have never used that function apart from pushing the button to see if it works.

Thanks for the reply.

I will hesitate to modify that solenoid from what you said.

You are right about not using it much.
If and when I go down into Southern California and hum around on the Pasadena to Bakersfield mountainous freeways is about the last time I used it last.

Of course, if you get it up to roll with other "speeders," you are best to leave it in overdrive and draft a SUV. Even an old Volvo can blend in, if it has ABS, otherwise it would be white knuckles for me.

The lock out, can be, way more relaxing.
I like riding and not driving everywhere I go. Driving is like working for a living for that almighty buck and it causes people to take too many chances.
(:) IMHO

Phil

i had the same problem as you except i did not install the bypass plate, rather a brand new solenoid. anyway the od still would not work. the remedy was to loosen the solenoid and then run the engine a few seconds which blew out the blockage. top up trans fluid and test. 4th gear (od) kicks in as it should at 38mph with light throttle. messy yes, but it worked. hope this helps
--
'91 244 200k auto

interesting you mention that fix. i was speaking with this morning with a skilled volvo mechanic who told me to do the same thing.

he said the outflow ought to spray out.

since one of the holes is an inlet hole will any fluid come out of that one with engine running

well i hope it works for you. this fix has been working in my brick for 2 years now... crossing fingers...got to admit it was a 'last ditch' effort to get the od working.

--
'91 244 200k auto

Yep- that should do it. Or just give it time. My OD hadn't worked in a long time and I had the solenoid replaced.The tech said I had a 50% chance of it working again. It took about 2 weeks but it just kicked in on its own one day.Most likely the hole was clogged up with crud. So, Please don't replace the transmission! Tinkerbelle.

I had the same problem. Refreshed the fluid, installed plate. My high gear kicks in at about 60-65mph.

thanks to all who replied.

1. all o rings were removed before bypass installed with only large outer ring utilized on install

2. below the solenoid on the case is a fitting which can be removed for a gauge to measure internal pressure when the trans is in drive. it needs to be in the 76-80 psi range. i am wondering if low pressure might prevent upshift into OD

that is my next step along with applying a mityvac vacuum pump with suction cup to the hole which feeds into the transmission rather than out of the transmission which flows quite nicely with the engine running

i am hoping it is something as simple as dirt in the hole

after that i am going to recut the slot between the holes on the homemade bypass plate to ensure they are wide enough.

if pressure checks out, no crud can be found by suctioning, the recut hole enlarged and a wire inserted into the input hole for fluid return into the transmission bottoms out as far as possible........does not remedy the problem i forsee no alternative but to replace the transmission.

opinions?

This thread found by a quick Google makes an interesting read.
https://volvoforums.com/forum/volvo-240-740-940-12/overdrive-ceased-function-38907/
Making sure that both of the O rings are removed when taking off the solenoid is critical. Could this be the problem here?

I second the check to make sure you removed the old o ring.
I didn't and first drive revealed no I'd
Removed the old o ring and od returned.

Hi,

You might be ready for a treatment of something on the order of "Trans X" solvent.
I'm not experienced automatics but I heard it helps with domestic transmissions that have shift issues.

On the M 46's I would pull the check ball under the drain plate and round caps. Most times it's the seat plate for the ball. The ball wears a groove into the angle. This affects pressure to that Laycock system.
Don't what does that in the automatic end of the overdrive shifting drum.

Phil