Good morning Spook. I see that you are online so I thought I might request your advice on a solenoid leak from the automatic transmission. The garage found it for me. It has been going through a litre of fluid in the space of a month's normal driving.

I had the car in for a check pursuant to a possible drive to the southern USA. The muffler is shot and the front motor mounts were collapsed enough that the mount was banging on the crossmember. I gave that last job to the garage but am considering my muffler options.

The mechanic found the leak using a kind of dye and I thought I might be able to deal with the solenoid myself.Does the solenoid need to be replaced completely or is there an o ring or something like that that could be installed. Transmission is working fine, just losing fluid through this component.

Are there any potential difficulties with solenoid replacement/repair that I should be considering? It seems to be in a relatively open space and available to wrenches, etc., but this is looking at it on the garage's hoist, not from underneath the car with everything dropping onto my head.

Dear muskox37,

Hope you're well. I've not had any problems with the overdrive solenoid, so have not had to replace one.

The over-drive solenoid has two "O" rings. The small "O" ring is part #1239834 and the large "O" ring is #1239835. MSRP is about $1 and $2, respectively, at a Volvo dealer.

I'd use the Volvo Brand item, as there's no reason to skimp on low-cost parts, that are not easy-of-access. The solenoid itself is part #1239928: MSRP is about $250; www.fcpgroton.com has an aftermarket item for about half that amount. Your report suggests there's no problem with the solenoid.

The first thing to do - before putting any tool on the solenoid bolts - is to clean the area around and above the solenoid housing. The goal: to have the metal so clean, that there's not a speck of dirt anywhere nearby. This ensures that no dirt/grit can enter the tranny, when the solenoid has been removed.

You may need a mirror - on a telescoping rod and with a U-joint - to be sure that all dirt has been scrubbed away. Use brake cleaner, or something similar, to blast away dirt, that cannot otherwise be reached. It is of paramount importance, to make sure no dirt enters the tranny during "O" ring replacement.

If the in-service "O" rings are obviously damaged, then you can be sure that's the source of the leak. I'd lubricate the new "O" rings with automatic transmission fluid, install them, and bolt-up.

Hope this helps.

Yours faithfully,

Spook

I thought I had the leak fixed. I ran it for a while and took it for a short hop around the neighbourhood and nothing on the floor.

But today I took it for a longer run and when I checked the garage floor later I found some transmission fluid spots. Not a lot but it hasn't had a chance to sit overnight. I will check in the morning but I have a feeling that the problem still exists.

Looks like I am in for a solenoid change. Wish I could report better news.

Dear muskox37,

Hope you're well. Slide clean paper (white, brown, or newsprint) under the tranny. That will show: (a) how much fluid leaked and (b) generally, whence it leaked.

If you can raise the car, while in the garage (keep the door open, in case you need to be rescued), securely tape a clean white paper towel as close as possible to the solenoid. Clean the metal with solvent, and then apply duct tape, to hold in place the towel.

Operate the car, as usual, and then inspect. If fluid has leaked from the solenoid, the paper towel will be pink. If the paper towel is still white, that exonerates the solenoid.

Hope this helps.

Yours faithfully,

Spook

Good Day Spook,

I was a little ahead of you on putting white papers below the transmission and did so when I parked the car last night.I just checked on the results.

There is a pink spot that is about two inches in diameter on the paper. It is directly below the crossmember but seems to be a little away from centre. Towards the driver's side of the car. It does not seem to be coming from the transmission mount nut but I will confirm that on my next go around.

I haven't lifted the car yet but can see some glistening coming from one of the transmission mount bolts. It is cold as billybedamned right now so I only get about ten minutes of going at it before I have to retire to the house.

At the moment I doubt that fluid from the solenoid would gravitate to this area so am suspecting something else, perhaps a drain plug, is leaking.

From memory, the quantity does seem to be less. Thanks to your cautionary note I did not rush ahead and order a new solenoid. Will get back to you within the hour.

Hmmm. Well I let it run for about five minutes up on the jackstand. Before that I wrapped the solenoid in a new paper towel as per Spook's recommendations.

Earlier I observed some glistening around the electrical 'hood' that covers the top of the solenoid. I have to remember that the garage traced the fluid leak to the solenoid using a chemical dye.

Fluid seems to be running down the crossmember to its lowest point and then dripping onto the floor.

Looks like I am in for a solenoid replacement. But I will confirm that before I order.

Dear muskox37,

Hope you're well. Having regard to low temperatures, can you wrap a strip of paper towel, such that it only goes around the top of the solenoid housing? If the towel is clear of the base (where the bolts affix the housing to the tranny), this test will show if there's a hairline crack in the housing, as distinct from a leak where the solenoid meets up with the tranny.

If the solenoid's top is not cracked, the solenoid's top may have slightly separated from the base. That allows fluid to bleed-out: the amount leaking is only a few drops.

If the solenoid's top has separated from the base, a new solenoid is required, unless you can see a way to press-down on the solenoid's top to close-up any gap. I doubt any sealant will work, because the fluid is under pressure, and because few sealants adhere to oil surfaces.

Hope this helps.

Yours faithfully,

Spook

Good Day Spook,

Well, things got a little worse yesterday when I took the car out for a forty mile trip on a local highway. This was after I had been trying the paper towel wrapped around the solenoid check and had found transmission fluid marking the towel.

I could not engage fourth gear and had to drive the whole way in third. I am thinking now that I might have broken the solenoid connector, at least that is what I am hoping. I have ordered a new solenoid but it looks like it will be a day or two before it arrives. In the back of my mind is the worry that a piece of grit went undetected and has made its way into the transmission.

The amount of leakage has increased again, back to its original quantity. I could have worsened the leak by my efforts to determine its source.

I am seeing quite a bit of information about people who have blocked off this solenoid with a plate. This modification has apparently solved their solenoid problems. Any thoughts on that?

Dear muskox37,

Hope you're well. I doubt any grit got into the tranny: you cleaned the area very thoroughly. Damage to the solenoid's connector is unlikely, unless you applied brute force. The connector's contacts may be oxidized and so not making good contact. The best way to clean connectors - especially those hard to access - is to use Deoxit, an aerosol oxidation/corrosion remover.

I suspect the solenoid has simply failed. Install the replacement solenoid. I'd guess that will restore proper function.

I recall reports from those, who blocked the solenoid with a plate. I'd only do this, if I did not have - and could not get - a replacement solenoid.

Hope this helps.

Yours faithfully,

Spook

Good day Spook and Jerry

I went back to the garage with a vibration brought about by the new motor mounts they had earlier installed for me and while they had it up on the hoist the mechanic installed a new [actually a used one] solenoid. The car is now running properly. Garage owner assures me that the vibration will disappear with a little running. If not, bring it back.

There was no charge for the solenoid installation. Very pleased to have found this Volvo garage. They also service Ladas, by the way!

Dear muskox37,

Hope you're well. Glad to hear that the solenoid has been replaced and now works properly.

I trust the problem was with the failed unit, and that the connector was found to be in fine shape.

Thanks for posting back.

Yours faithfully,

Spook

Thanks to you and Jerry and Volvo from Heck. . . and my local Volvo garage. Many thanks again to you all.

Good Day Spook,

I will take your good advice and leave it alone until I get a replacement unit. Thanks for your opinion on the solenoid blocking plate as well. Won't bother with that.

I will probably get the 242 going again and start undoing the crossmember and solenoid this afternoon once the sun has started to warm up the garage.

Hope you are having a nice day as well.

There is an adapter plate sold by IPD, which works well. However it does not allow the downshift button to function, so using 3rd in say, towing, is not possible.
The same thing can be done by making a slot in the bottom of a solenoid, but I don't know if the solenoid will still leak out the top, if it's already doing so.

Hello again Spook

Once again, thank you for your input. We are both on the same page. I am about eighty per cent certain that the solenoid is leaking from its top and needs to be replaced. I have spoken to the garage and they are looking for a replacement for me right now.

When I did your paper towel test, I simply wrapped it around the solenoid and ran the car for about five minutes until it was good and warm. I did find pink fluid on the towel so that pretty well confirms that it is leaking. I might have some other leaks but I know that the solenoid is a contributor if not the only source of leaking.

When I had the car up on the jackstand running, the drips fell onto the paper more to the passenger side as would have been expected. It would seem the fluid is running back from the solenoid and finding a way to get onto the crossmember and then to the floor.

Now that everything is pretty clean it will probably cost me an afternoon to install the new solenoid. . . and I know what to expect. I will keep you informed.

Thank you Spook, Heck and Jerry. Much appreciated. I feel more confident now going forward. Will get back to you for further instruction if needed and to make a progress report.

I had to put the 1982 GLT back on the road and it didn't appreciate being woken up in the middle of its winter hibernation!

Thanks again for your valuable input Spook.

The garage put some dye in the fluid and after a drive found the dye emitting from the solenoid. Thus I am fairly confident that the o rings are at the bottom of the problem. I read another thread about the solenoid [to which you were a contributor] and so am aware of the cleanliness issue.

Thanks again,

Bob aka muskox37

On one of my cars, the top of the solenoid itself had come apart and was leaking. The bottom where the seals are was fine.

The very reliable garage owner where I take my car said this was a distinct possibility, i.e., that the leak could be coming through the electronic part of the solenoid and not through the oil rings. That would mean a new solenoid of course. Not sure if a visual examination will reveal this or not. I will take Spook and Heck's suggestions and PB blast it for a while before attempting a removal. I will also blast it with brake cleaner.

Is there much to dropping the crossmember? If it will give me good access and is not too heavy a job it might be worth doing.

A friend who does mobile Volvo repair does these in about a half hour, on the side of the road. He puts one set of wheels up on the curb, lowers the trans a bit, pulls it out, etc.
He has good used ones for sale, Way less than a new one, prolly $40-50 shipped. Let me know if interested.
bikeguy (at) fastmail (dot) fm

Jerry,

I just saw your bikeguy@fastmail.fm. address. Is this his email address?

No it's mine. He does not have a computer, I am sorta his agent for online stuff.

Jerry, I take it that your friend drops the cross member and then pulls the solenoid and that he puts the driver's side up on the curb [echoing Spook's comment that he goes in through the driver's side]. What takes him half an hour will probably take me a week. But the sun has arrived on the wet coast for a while and it is warming the garage so I am warming to the job.

I bought the solenoid seals just in case that is indeed the problem. Cost me nigh on ten dollars for the two of them at my local Volvo/wrecking yard supplier [thank you Spook for supplying the part numbers].

If it turns out that I need another solenoid I would be in the market for one so let your friend know. I will be taking a run at it very soon, probably Monday so that I can get parts if I need them.

I would like to head south in early February if at all possible but the beauty of car travel is its flexibility.

bob

Dear Muskox37,

Hope you're well. It is not hard to remove the transmission cross-member. First, put a small jack under the transmission pan, and put atop the jack, a small piece of lumber (2" x 8" x 12"-long [or so]), to support the transmission. Second, raise the jack so that it lifts the tranny by 1/8". This will hold the tranny securely, once the cross-member has been removed, but keep enough pressure on the wood, that the jack stays in place.

The transmission cross-member is secured by four hex bolts (17mm, if I recall corrctly). There's also a hex nut in the center (15mm?), that must be removed. As with other under-body fasteners, saturate them with PB-Blaster or similar penetrating oil.

I found it easier to reach the bolts from the driver's side of the car: the passenger-side bolt heads face the driver's side of the car. I used an 18" breaker-bar to free the bolts.

Before re-installing, I'd coat with anti-seize, the bolts, and the stud, from which you remove the 15mm hex nut.

Hope this helps.

Yours faithfully,

Spook

Hello again Spook,

I had a look at the situation today and blasted everything with PB Blaster as per your instructions.

My car has an aluminum cover above the exhaust that extends slightly over the two cross member bolts on the passenger's side. I haven't given it a try yet but I might have to undo one of the small nuts that holds it to the body to access the bolts. They are clearly visible but there might not be enough room for my socket wrench.

I see three bolts on the solenoid, two vertical ones on each side of the electrical connector and a horizontal one on the side. Is that horizontal one a holding bolt or can I leave it in place.

I will let the PB Blaster do its stuff for a while before attempting the removal [having first cleaned everything out with brake cleaner of course].

Dear muskox37,

Hope you're well. I've changed a tranny mount on a '95 940 - it was a while back - and I do not recall being troubled by the exhaust shield. Either it did not get in the way, or it was easy to remove.

So far as I know - I've not had to remove this part - the solenoid is secured by two bolts. The third bolt might secure the wiring harness.

I'd repeatedly saturate the area with PB Blaster, i.e., once or twice a day.

Hope this helps.

Yours faithfully,

Spook

Thanks again Spook. I will give everything another shot of PB Blaster this morning before tackling the removal this afternoon. should I expect much in the way of transmission fluid to flood out of the solenoid hole? I have not drained the transmission. There is a catch basin at the ready.

Everything around the area of the solenoid looks pretty good I have to say. Dirty but not filthy with dirt and oil. This car has pleasantly surprised me with the general condition of its body. Must have been the eight easy years it had in Georgia before coming to the land of snow, ice and salt.

Dear muskox37,

Hope you're well. I've never pulled a solenoid, but think it unlikely that fluid will gush from the opening. The reason: the tranny's pump is not running, because the engine is "off". Further, the solenoid is mounted on a flat, upward-facing surface. Third, for fluid to drain, air has to enter. The only opening in the system - beyond that made when you remove the solenoid - is the transmission dipstick tube. That opening is closed by the dipstick, which has on it a rubber sealing ring. In short, I'd not expect more that an ounce of fluid to escape.

If - when you describe the area around the solenoid - "dirty" means the metal is dull/corroded, that's fine. If the area around the solenoid still has dirt on it, scrub that area - with a wire brush, or steel wool, or a pot-scrubber, or fine sandpaper - until only bare metal is present. Once only bare metal is present, wipe the area with a rag wet with brake cleaner, or a similar solvent.

You need near-operating room clean. The reason: small particles of grit can do a lot of damage inside a transmission, most parts of which are made to very fine tolerances.

Hope this helps.

Yours faithfully,

Spook

Good afternoon Spook,

I will now attempt to upload a picture of the solenoid. I am trying to confirm that what I suspect to be the smaller 'o' ring is, indeed, that.

I do not want to ruin another part that looks like it should be the smaller ring but seems to be somewhat different.

The picture shows the top of the solenoid hanging from the side of the transmission. The identification label for the transmission can be seen dimly in the background.

1995 940 automatic transmission solenoid seal

Dear muskox37,

Hope you're well. The smaller "O" ring is shown in the photo, still in the solenoid housing. The larger "O" is missing, but goes in the recess near the perimeter of the solenoid housing.

I'm glad to see that the work area is very clean. That is very important.
I trust only a very small amount of automatic transmission fluid dripped from the solenoid, when you removed it.

I do not know what is meant by the words, "looks like it should be the smaller ring but seems to be somewhat different". Without having the in-service and brand new items next to each other, I can't be sure to what your words refer.

Hope this helps.

Yours faithfully,

Spook

Thanks again Spook,

Just wanted some confirmation of my suspicions before I went ahead and removed the smaller seal. I will probably have to destroy it to get it out of there.

When I put the new seal up to that location the shaft seemed to be too small for a seal with such a large inner diameter. Usually 'o' rings fit tightly to the shaft but that is not the case with this one apparently [but it is the one that follows the part number you provided me].

I spent two days cleaning and rinsing with brake cleaner and scraping out the small indentations with a mechanic's pick and blowing the whole thing out with forced air and feeling for sand and bits with my fingertips and inspecting everything with the mirror before I removed the two bolts. You put the fear of God and Volvo into me Spook.

There was no leakage of fluid to speak of, as you predicted.

Input much appreciated.

I couldn't see the picture in the original message so am trying again.

Good morning Spook,

Thanks for the special alert about dirt around the solenoid. I haven't started to clean up the solenoid and its area yet but will take out the cross member first and then clean everything up to your specifications. Then and only then will I remove the solenoid.

Right now the solenoid is relatively clean which is a good start. Good to know that there will not be a gush of fluid when it is pulled out.

Tbanks again for your valuable input.

To add to Spook's instruction on crossmember removal--the purpose is to be able to lower the transmission a little so the wrench has a better angle on the bolts and room to swing it for loosening and tightening. It is not absolutely necessary to separate the crossmember from the trans mount--if the mount is bad it will become apparent with the crossmember hanging. -- Dave

I recently did a solenoid modification on 940 model. I found dropping the rear crossmember gave me much better access to the solenoid bolts. The client & car were new to me and dropping the crossmember also gave me the opportunity to discover a completely shot tranny mount. Use a good fitting box end wrench for the solenoid bolts--they may be very tight. -- Dave

I will try to upload a picture of the transmission mount. It has one chunk of rubber loose and there are a couple of tears but in general it seems to be still doing its job [this is to the untrained eye however].

I have outlined in red the loose chunk of rubber and used an arrow to point to its proper placement.

Would you put it back in place?

Well, it looks like I will not be able to upload the picture. When I click IMAGE LIBRARY [UPLOAD/SELECT] it sends me to something called BRICKPIX and then seems to want me to browse pictures to find something similar to my situation. There seems to be no way to go to my own files and upload the particular one relevant to the discussion.

I did finally figure out to 'submit my image' and entitled it Volvo 940 transmission mount but I don't know where it is now and cannot seem to connect it to this message. Sorry. I am a point and click moron when it comes to computers.

1995 940 automatic transmission solenoid seal

I will try to cut and paste the image now that I have found it in BrickPix.



I am unable to see a picture. Only the script. Can you see it?

I found it! I uploaded it! Wow!

Dear muskox37,

Hope you're well. That tranny mount is at the end of its service life. The rubber - in the center square - has compressed to the point that it is no higher than the surrounding steel. As a result, the tranny rides on the mount's steel cup. The want of a rubber cushion means driveline vibrations transmit to the cross-member and into the car.

Motor mounts are at end of their service life, when the oil pan is 3/16" or less from the cross member. If the mounts aren't replaced then, the oil pan eventually will rest directly on the cross-member, which gives rise to lots of noise and vibration.

I trust the cross-member came-off without great difficulties. It goes on easily. Sometimes a hydraulic jack will sag a bit, so you may need to raise the tranny a bit, to ease cross-member reinstallation.

Hope this helps.

Yours faithfully,

Spook

Hello again Spook,

I have just spent an hour trying to find torque specifications for the transmission mount and the crossmember bolts without success. I will now go to my 240 manual and use the information from that book to finish the install. If the specifications are at all different I would appreciate your input. I just cranked on the crossmember bolts using an extension and expect this will be adequate. I would like to be a little more exact with the transmission mount bolt if at all possible.

Seems to be very difficult to find some fairly elementary bits of information.

Just about there. Will try the car out today to see if I still have a leak.

muskox37

I just make them nice and tight and don't worry about specific torque numbers on my 240 motor and trans mounts, it's not that critical.
Dan

Hi Dan,

You are right of course. Even my 240 manual did not have any settings for this particular application. Finally I just gronched the crossmember bolts using an extender on the breaker bar and finally did the same for the transmission nut, without using the extender. I expect they will stay in place.

Bob

Dear muskox37,

Hope you're well. The Volvo pocket data booklet - Cars: 700, 850,900 (1991-1996) has no torque specs for the tranny mount or cross-member bolts.

I've used a standard 1/2" ratchet, 'til tight, and used an 18" breaker bar, to give a final push. This seems to have worked. The trans mount is held to the cross member by two hex nuts: it is compressed between the tranny and the cross-member, so I'd not worry about it coming loose.

I infer that the solenoid seals went smoothly into place, and that you found no defect in the solenoid itseld. If so, congrats on a job well done!!

Yours faithfully,

Spook

Thanks again Spook and Dan. I will set out to buy a new transmission mount today. The garage changed out the motor mounts after pointing out to me when the car was on their hoist that the mounts had, in effect, collapsed. They are apparently some kind of hydropneumatic arrangement and it would appear the interior oil had escaped sometime in the past and the motor was in danger of rubbing on the front cross member.

When I brought the car home from the garage it was vibrating a lot more than when I took it in. Perhaps the new front mounts put more pressure on the transmission mount and thus the vibration. Regardless I will change out the transmission mount and see what is the outcome. I will take it back to the garage if the vibration persists.

I plan to clean up the transmission solenoid area today and if weather permits I will try to remove the solenoid.

Thanks again for your valuable input.

I would go ahead and replace it while you have the damaged one out.
Dan

Would you happen to know the size of the solenoid bolts Dave? I am also thinking of following your advice on rear cross member removal. Bob

If I'm remembering correctly--the screws had an 8mm shank and 12mm head - Dave

Dear Volvo From Heck,

Hope you're well. May I leverage your sound advice? Saturate the solenoid bolts with PB Blaster or an equivalent penetrating oil. The oil will percolate through micro-channels in any corrosion, and so weaken a corrosion bond. If that eases bolt removal and spares bruised/cut knuckles....

Hope this helps.

Yours faithfully,

Spook