Auto transmission: no OD/ Fourth Gear

Locked
User avatar
ynwa
Posts: 124
Joined: Sat Mar 26, 2016 10:59 pm
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: L300 Starwagon TD
Location: Victoria

Auto transmission: no OD/ Fourth Gear

Post by ynwa »

Admin: thread tidied up for inclusion in the Technical Reference Library. Original thread is here:http://www.delica.ca/forum/viewtopic.php?f=6&t=17741

So I've done a ton of work on the little bus (my project post is waaay overdue for an update). However one lingering issue (among others, hehe) is that I don't remember ever feeling 4th gear in my auto. This post is possibly a vehicle for a series of condolences which I will also appreciate, however there might be something out there in your collective minds that might just do the trick.

Here's the skinny. Initially I was having issues with a high RPM 3rd gear shift so I performed the following so far.
* Changed the tranny fluid and poured in a can of Seafoam. Ran that for a couple of weeks with some burns up to 80 on the hwy.
* Drained (also drained the torque converter based on another good post).
* When I received the van the 'throttle kickdown linkage' was disconnected (bolt fell out probably). So I reconnected it. It was set to a very narrow setting, like 15mm.
* After reading Gbear's post I tested it at 32mm and had slipping from 1st to second so backed it off again.
* Just before our trip to Carmanah I dropped in a bottle of Rislone trans repair.
* Bus ran fine although trying to drive 100 in 3rd was a stretch at 3,500.
* I've just backed off the linkage even more so I'm probably closer to 25mm gap from 'nub' to cable housing.
* Shifting is happening a bit quicker but still seems to slip from 2nd to 3rd at high revs (need to back off the pedal).
* I've tried to set the 'free play' in the kickdown but I really can't tell what's freeplay and what's worn out plastic linkage.

I recently blanked the EGR so my TPS is moot. I'm just using generic Motomaster ATF.

Bring the condolences. :)
1991 L300 TD Low Roof
1992 L300 TD Low Roof
1992 L300 TD High Roof
User avatar
Growlerbearnz
Posts: 2041
Joined: Sat Jun 26, 2010 1:58 pm
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: Delica P25W
Location: New Zealand

Ain't Got No (satisfaction) Fourth Gear

Post by Growlerbearnz »

I'd suspect the OD solenoid on the gearbox isn't getting power.
Solenoid.JPG
Solenoid.JPG (140.28 KiB) Viewed 9713 times
EDIT: the wiring diagram I had is wrong. There's nothing electrical to prevent OD engaging when the transmission is cool. Instead there's a slight restriction in one of the hydraulic ports inside the transmission, and thick, cold fluid can't build enough pressure to engage the OD. It's simple and dumb.

The wiring diagram alleges that there's a coolant temperature switch that only lets it operate once the engine is warm. I have no idea where that switch is, but it sure seems to work that way. Anyway: with the ignition turned on and engine warm (but not actually running) if you climb under the van you should be able to hear the solenoid clicking if someone in the cab turns the OD button off and on. (I'm guessing the OD off light on the dash works.)

If you can't hear it clicking in and out, I would try applying 12V directly to its connector. If it clicks then, I would leave it connected and go for a drive to confirm that you have 4th- and then figure out where the break in the wiring is. Once the engine is warm, the gearbox should drop into 4th at about 55kph if you're being gentle.

The TPS doesn't do anything gearbox-related. It's there for the glow plug controller only.

The full throttle kickdown cable adjustment (that 32mm one) mostly effects full-throttle gear changes. If your 1st-2nd shift is playing up, check the cable adjustment at idle (1-2mm free play). That said, 1st-2nd is always a bit mushy, it can take about a second to complete the shift if you're driving normally. 2nd also does this weird thing where it feels like it's slipping, but locks up if you put your foot down a bit harder. I have no idea what it's doing, but they all do it to some extent.

Additional resources from the Volvo Club. Bear in mind that, despite using the same auto gearbox as us, a Volvo is not identical to a Delica, and some things (like wiring colours) might not match exactly. https://www.volvoclub.org.uk/faq/Transm ... msSolenoid:

AW 70/71 Overdrive Problems: Wiring to Solenoid, Solenoid.

Electrical & Wiring Problems:

The overdrive solenoid should click on and off with a very noticeable click. You need to be sure you're getting 12 volts at the solenoid. If you haven't got 12 V, you need to check the wires.
Wiring Connector: The plastic wiring connector which connects to the overdrive solenoid (attached underneath the car at the rear of the transmission) can come loose.

Sometimes there is corrosion in the joint between the connector and the wire..it may look fine and even will light a test lamp but will not allow enough amps across it to fire the solenoid. Take it apart, clean and deoxidize, then reassemble with silicone grease.

Solenoid Operation/Diagnosis:

The solenoid is normally closed, cutting off the fluid flow necessary for 4th gear or "overdrive". When energized (normal operation- "OD Off" dash light NOT illuminated) the solenoid opens up and allows the trans to shift into 4th. The solenoid must pass fluid through when energized, or it's either not working or plugged up with dirt. Just because it "clicks" does not mean it is passing any fluid. The first test is to park in a quiet place, open the drivers door and switch the OD on and off while listening for a click under the car. If you don't hear it then it is bad. If you do hear a click that does not necessarily mean it is good: it could be dirty and not passing fluid.

[Steve Sakiyama] There have been a few posts on autotrans overdrive Overdrive Solenoidproblems (won't shift into 4th) when the brick is cold. The problem disappears when the car warms up. I have an AW71. When cold it would not go into 4th (OD) until the car had been driven for 10 minutes. This would happen more and more frequently until it was a regular pattern. I checked/dealt with fluids, OD relay, wiring, and downshift cable but the ultimate problem was the overdrive solenoid which sits on the side of the tranny. Although I had bench tested it and it seemed fine,an experienced tranny tech said it just doesn't sound and feel right. Replaced it with a used one (with the two inner o-rings), and the brick is fine. [DougC] According to Bentley, with the solenoid in your hand and disconnected, you should cover the oil passages between the o-rings, and blow through the hole on the end of the solenoid. The valve should be tight, and no air should pass through. With it energized with 12 volts, you not be able to blow air through with the same holes uncovered. It says also to check for blocked passages and damaged o-rings.
ODSolenoidBoltAccess.gif
ODSolenoidBoltAccess.gif (63.45 KiB) Viewed 8298 times
Dirt. [Rob Bareiss] Replacing the solenoid requires that NO dirt get in that transmission. Lots of brake cleaner, Gunk, power washing, and probably use of a toothbrush and more brake cleaner will get the area acceptable. You might follow up with compressed air delivered by a J-tube to remove dirt and little rocks lodged up behind the solenoid. Haynes suggests the use of a sheet of cardboard over the trans, up against the tunnel to keep grit from falling in from above. Dirt and transmissions disagree.

Don't get any dirt into the solenoid when you replace it. This is a filthy area and it's easy to do this. The plumbing internal to the solenoid unit, which has a right angle turn at the valve seat, can plug up. You may have to pull the OD solenoid, rig it up to the battery to turn it on and blow it out with WD40, carb cleaner, compressed air, or any similar pressure source, preferably with a little straw to get down into the holes.

[Editor] Two users reported that removing the solenoid and turning the engine over seemed to pump enough oil through the recess to clean it out and enable operation. This is messy, though. [SML] Before re-installing the solenoid, clear the oil passages in the transmission by slipping a tray under the tranny, starting the car and quickly shifting the auto trans gear lever from P through R,N,D,2,1,P then quickly off. About a 5 second process. A flood of trans oil will squirt out from the car hopefully clearing any blockages.

[C. McGrew] My transmission was leaking fluid and was oil soaked from an engine rear main seal leak. The solenoid rubber cap becomes brittle and then it's good bye. Be sure to buy the two o-rings for the solenoid. Coat o-rings with plumbers or silcone grease for sealing and ease of install. It's not that bad getting your fingers in the correct position to replace the two bolts. Re-torque to 7-12 ft-lbs to tighten the solenoid bolts.

Rusted Bolts. [James Souther] If the solenoid mounting bolts are rusted, the lockwasher is only rusted to the solenoid flange and the bolt head, not in the threads as the case is aluminum so PB Blaster or Kroil will help but not solve (no pun intended). If you use penetrants, use starting fluid or brake cleaner to clean off around the solenoid base before you start as both dirt and penetrants are not good for the inside of the transmission. Second, free the solenoid wire cable and the brackets before trying to loosen the bolts. This lets you get better access if you flop that out of the way. If needed you can take the nut off the shift shaft input and move it away, however, you need to hold the lever so you do not stress against the transmission valve assembly inside. The lever goes on with a rectangular notch. Third, attack the bolts which set very close to the solenoid body and come out by hand after a turn or two. IMHE the original bolts seem way overtight due to being threadlocked so what works is a quarter inch 6 pt socket with extensions to get down on top of the bolts or a thin box end wrench and lots of force. The posture is pulling the car and the wrench or ratchet together so you can put enough force on it. In a dozen or so times, the bolts mostly "crack" loose. When you get it out, check to make sure the old o-rings are not stuck on the transmission flat. Finally, take heart, installation is a breeze compared to taking it out.

Eliminating the Solenoid and the Manual Downshift System: Solenoid Modification for OD Troubles

You can also pull the solenoid entirely, replacing it with a metal plate, and remove the ability to use the button to manually shift down into third. See the link below for IPD's solution to solenoid troubles.
ODSolenoidModification.gif
ODSolenoidModification.gif (78.86 KiB) Viewed 8298 times
[E. J. Ohler] Forget about a new $150 solenoid and $50 relay: take the solenoid out, cut the wire off and cap the end, grind a small groove between the center hole and aft hole in the solenoid face, and reinstall to allow fluid to move and disable the solenoid as a solution to solenoid troubles. Use a Dremel 1/8 inch grinding tool (the metal is hard so you will use two) or a diamond bit. Clean the matching holes in the tranny using drill bits the same diameter, but don't drop them into the transmission. Replace the outer O-ring but not the inner where the groove passes through. From start to finish this is a 3 hour job that saves you a lot of headaches. You don't need the manual 4-3 downshift in most instances anyway.

Solenoid with Ground 1/8 Inch Groove
ODSolenoidModification2.gif
ODSolenoidModification2.gif (33.84 KiB) Viewed 8298 times
Solenoid Quality Reports:

[Tip from Dan Marino] My recently-installed Scantech OD solenoid failed. I discovered that the rubber top cap (the part where the electrical wire attaches to the solenoid) had totally split away from the metal solenoid valve parts. Basically, the top blew off of the thing. The result, massive transmission fluid leakage. My conclusion is that this ScanTech overdrive solenoid suffers from poor quality construction, cheap-o materials, and design flaws. The next day I was able to pull an original Volvo overdrive solenoid from a junker for a cost of $5.25. A quick comparison showed the Volvo part to be of superior design, more metal, and less plastic/rubber.

IPD's Overdrive Blockoff PlateSolenoid and Overdrive Removal. [Ken Crossner] For you folks who wish their automatics were simply completely automatic without any tendancy to fail and lose 4th (especially during this gas crisis time), IPD came up with a solution! They're selling a Solenoid Bypass Plate (product code MD7071K - $39.95.) Remove the solenoid, cover the hole with this plate, and you're left with a 4-speed automatic transmission -- the 4th (OD) gear works normally, and you can dispense completely with all the other components (relay, shifter switch, wiring, etc.). Nothing left to fail, ever! You merely lose the ability to manually downshift into third gear, which you probably never used much anyway. You can remove the overdrive relay to turn off the lamp permanently and remove the power to the +12V lead to the solenoid.
ODBlockOffPlate.gif
ODBlockOffPlate.gif (16.2 KiB) Viewed 8298 times
[John Orrell] there is a almost free way of doing this. Remove the stock solenoid, remove the inner O-ring and machine/grind a groove in the face of the solenoid between the two small holes. Replace the outer O-ring (not exactly free, but cheaper than 39.95) and reinstall the solenoid.
Nothing says "poor workmanship" more than wrinkles in the duct tape.
User avatar
ynwa
Posts: 124
Joined: Sat Mar 26, 2016 10:59 pm
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: L300 Starwagon TD
Location: Victoria

Re: Ain't Got No (satisfaction) Fourth Gear

Post by ynwa »

Oh, man, that's exactly the glimmer of hope I was looking for! I'll let you know how it goes over the weekend. You're replies are nothing less than heroic! :-D
1991 L300 TD Low Roof
1992 L300 TD Low Roof
1992 L300 TD High Roof
User avatar
ynwa
Posts: 124
Joined: Sat Mar 26, 2016 10:59 pm
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: L300 Starwagon TD
Location: Victoria

Re: Ain't Got No (satisfaction) Fourth Gear

Post by ynwa »

Hey! So I checked the wiring and there was power to the Solenoid with engine warm and ignition on.
I suspect this means that the Solenoid is toast? My dash light works fine.

I'm going to check RMI and see what they have.
1991 L300 TD Low Roof
1992 L300 TD Low Roof
1992 L300 TD High Roof
User avatar
Growlerbearnz
Posts: 2041
Joined: Sat Jun 26, 2010 1:58 pm
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: Delica P25W
Location: New Zealand

Re: Ain't Got No (satisfaction) Fourth Gear

Post by Growlerbearnz »

That's the conclusion I'd draw as well. Replace the solenoid and keep your fingers crossed. Could you hear it clicking as it was turned off and on? I mean, it might be physically jammed so it'll click but not actually do anything, but if it was silent then that's definitely a problem.
Nothing says "poor workmanship" more than wrinkles in the duct tape.
User avatar
ynwa
Posts: 124
Joined: Sat Mar 26, 2016 10:59 pm
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: L300 Starwagon TD
Location: Victoria

Re: Ain't Got No (satisfaction) Fourth Gear

Post by ynwa »

Ya, it was silent as I had someone flicking the button. I also gave it a few 'love taps' from a wrench but nothing shook free. :) Sure hoping for 4th gear sometime in the near future.
1991 L300 TD Low Roof
1992 L300 TD Low Roof
1992 L300 TD High Roof
User avatar
ynwa
Posts: 124
Joined: Sat Mar 26, 2016 10:59 pm
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: L300 Starwagon TD
Location: Victoria

Re: Ain't Got No (satisfaction) Fourth Gear

Post by ynwa »

Hey! Great news! I've got 4th Gear, wahoooo!!! It was the OD Solenoid. Such a small little thing affects such a major issue. Pulled one off a wrecked L300 and was quoted over $300 for a NOS part.

Only thing I notice now is that the gears shift pretty close to each other. This is probably normal but thought I would check. 2rd to 3rd has always been a bit 'slushy'. Feels like it's slipping but from what I've read this is sort of normal?

Anyway, great news if anyone else has this issue and is wondering about the trans. After checking for voltage at the SOL connector, try a used SOL.

Cheers.
1991 L300 TD Low Roof
1992 L300 TD Low Roof
1992 L300 TD High Roof
Locked

Return to “Drive Train”