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[How To] Accumulator Mod with Transmission Inside

Fumomike

New member
Joined
Sep 29, 2016
Location
Valdosta, GA
Hey Guys
So I just did the Accumulator mod on my 1990 760 Turbo wagon. I thought it would be a good idea to let anyone know that it is extremely easy to do with the transmission in the car, and my story on doing it with very little knowledge on how transmissions work. You just have to be careful at a few steps.

Guide to Accumulator Mod with Transmission in the Car, even if Everything Goes Wrong Attempting It

First, Things to Note:

  • You should do this with a partner. Especially if the car falls down on you, you can get crushed together, :). Jokes aside, Its also pretty hard to hold stuff up and bolt things down by yourself. So a partner is useful for that kind of stuff.
  • One is that the Valve body gasket is extremely brittle and can break easily(Not the pan gasket but valve body gasket). Mine actually broke a little on pretty important sealing areas. So far I have no idea if that has affected anything but yeah for everyone else be careful when removing the Valve body. Its like a Filmy thin looking piece of thing when you get to take off the valve body.
  • Another thing that is important is that the Filler Tube is a *** to remove from the pan. Enjoy the frustration and stuckness, i recommend using WD40 on it to break up some of the dirty deposits that have probably built up on it. Don't be like me and a friend when we put two wrenches and turn them opposite ways. We didn't realize that they were three pipes over each other so we ended up breaking off the pan hole pipe :). This led to an additional 2 hours of what would've been a easy 2-3 hour job. I had to find a friend to mig weld it for us as our stick/arc welder just wasn't cutting it. Also the dipstick filler tube is connected to 2 bolts on the starter motor which is absolutely super hard to get out unless you have a Long ayuss extension.

  • Then another annoying part is the kickdown cable which you should see when you are under the passenger side of the car. I don't have a picture of it(sorry) but its basically a spooling circular piece that goes besides+beneath the valve body. You will need to remove the wire from the spool and remember its original position when putting it back on. Also make sure you remember the original position of the valve pipes and the shifter thingy on the drivers side :). There should be 5 notches on the teethlike shifter thingy. Make sure it goes back on correctly and fit properly. It took two and half people for me to do it. Two to hold the valve body up and the other to start back in the bolts.
  • The Accumulator Mod with tranny inside is pretty easy actually hahah. 2-3 hour job if you force yourself to work fast enough.


How I did the Accumulator Mod
1. Jack up the car- You only technically need 2 large jackstands to jack the front-midsection of the car up so you can get to the Trans pan. I recommend setting parking brake and putting stuff to prevent the car from rolling. Make sure your on a flat surface or else your going to have to jack it up slowly and carefully like i did, which is dangerous.

2. Remove Trans Pan drain bolt. and drain the transmission fluid. It shouldn't take long as this is only part of the large amount of trans fluid throughout the entire tranny. On a scale of 1-10 dirtynes expect 2/10 transmission fluid to come out onto you.

3. Remove Trans Pan. There will be multiple bolts(i think 10mm, or smaller) that hold the trans pan up. Also there is a dipstick tube/filler that you use to fill the transmission. Be careful when removing this as incorrectly thinking two nuts will spin will cause problems later(welding it back on :( ). Just turn the smaller nut side on the outside/closest to the starter motor. On a scale of 1-10 dirtyness expect 4/10 transmission fluid to come out onto you when removing the pan.

Optional Step: There should be a tiny magnet on the bottom of the pan to collect any metal that breaks off. Feel free to add more of similar sizes...I think...

4. Remove Valve Body. Okay this may seem intimidating to look at such complex machinery; aka the transmission but DONUT be AFraidz!! Literally i just took a beast mode impact socket air gun from Harbor freight and took out all the 10mm bolts that the thing could fit on. Also you can guess which 10mm bolts are holding up the Valve body. Its basically all the ones on the side. Try to remember the lengths of each bolt because there is basically 3-4 different size bolts. Or you can be like me and use common sense to figure out which size bolt goes to which hole.
Expect 500% transmission fluid to gush out at this stage. Despite draining the tranny fluid on the pan, there might actually be more under the valve body lol. This is probably the most dirty part.

Optional step=Change Filter on Valve body, mine didn't have anything on it, must mean a healthy transmission :).

5. Leave One bolt on the drivers side of the transmission valve body slightly in because the kick down cable needs to be pulled out of the spindle mechanism to fully pull the valve body down. This is where your partner will shine as he can help hold up the valve body while you get a flathead screwdriver in there to remove the small kickdown cable. Literally the cable and that bolt i told you to leave in is the only thing keeping the valve body stuck up there. Remove bolts and valve body(be careful with the gasket!!!)

6. Okay now you should clearly see the accumulators (3 pistons). The middle small piston for me had a secondary spring that might pop out too along with the valve body. Pop out the accumulators with a Air sprayer thingy(thinner rod shaped the better) from harbor freight. There should be four little tiny holes where you can stick the air sprayer in. Watch youtube videos from searching google for "accumulator mod." for more info. Put your hand in front of pistons when doing this as they can pop out and hit you.

7.
Find some thick diameter bolts, cut them to the lengths of the rear springs(behind the pistons), and put them in just like some of the youtube videos and other forum threads(only can find 2 easily). I think full length rods will make a bigger difference. I just took 80% of the spring's length and put a bolt in there. I also grinded them down a little to make it smoother looking.
8. Pop accumulators back in by hand with bolts in the springs. Then put everything back together. all 10mm bolts go in to respective sized holes on valve body. Kickdown cable on passenger side and shifter thingy on drivers side will be tough as hell to get back in but im sure you guys can do it. :) Place new gasket for pan and walah, accumulator mod done. At this stage i had to weld my dipstick fill tube back in :(, don't make the same mistake as me. It should be a quick 2-4 hour job. If you have any leftover 10mm bolts(i had 3) then they might be behind the Filter. Dont forget the trans fluid.

PicTuRez

Beast Mode Harbor Freight Impact Gun:
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The Darn Filler Dipstick Tube
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Crossthreaded Filler Dipstick Tube Turd
i1VfiZVl.jpg

KcNrzEQl.jpg

Popping out accumulators with Harbor Freight air hose, this is pic of valve body off and accumulators in the open.
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Valve Body off and accumulators shown.
1gF5ScAl.jpg

Valve Body, filter is on it too. Also picture of the hole made by accidentally breaking off filler dipstick tube.
1ZAuMmml.jpg

It looks so shiny right :)?
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Grind Them Bolts down!
vDfhnall.jpg

Finished with upgrades on my wagon basically. Im going to fix the body now and make it look stock again.

Here is my new project a 93 740(yas it says 740 for some reason) Turbo Wagon. Someday when im older, i'll engine swap something fast into one of these volvos :')+turbo.
sT4dp9Xl.jpg
 
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It's easier with the tranny out. There is a thread like this already that also includes the check ball mod thing but it is good to have a little more detail in this write up I think
 
I did mine with it in there. It's completely doable, but it is hellishly fiddly. Plus, you have ATF dripping all over your face which is awful.
 
It's easier with the tranny out. There is a thread like this already that also includes the check ball mod thing but it is good to have a little more detail in this write up I think

Awesome write up, this will help me in the coming days

I did mine with it in there. It's completely doable, but it is hellishly fiddly. Plus, you have ATF dripping all over your face which is awful.

Hahah yeah I was bored and wanted to add more guides to the ones already out there. With a second person it is pretty easy actually. Don't break anything off and make sure you put everything back together properly then everything will be fine. It's pretty much a free upgrade besides the gaskets, filter, and tranny fluid.
 
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