Recently completed an engine out repair and resealed the transmission per one of the how to threads which was very helpful. I elected to replace the reverse friction disks and reseal the pump with inner and outer lip seals as well as new torque converter seal, new paper pump cover gasket and large o’ring. The car shifts well and the reverse delay is much better. Unfortunately, I have a smelly leak of smoking transmission fluid on the exhaust crossover below the bell housing. It doesn’t seem to leak until the engine is running. I coated the seals and o’ring with fluid and torqued everything per the specifications. Cannot imagine what is leaking. Any ideas? I plan to try running a borescope into the bell housing to see. I need to be sure before pulling it out for another try. Thanks for any help. One possibility is I did not use a thread sealer on the pump cover bolts. Other than that I have no idea.
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Transmission pump leak
- Thread starter Phoenix127
- Start date
The pump is fairly simple on the 722.3 as you say its hard to think of the Paper gasket leaking.The pump cover bolts don't require sealant, IIRC. The only sources I can think of are the front pump O-ring, and converter seal. The paper gasket isn't likely to be at fault. @JC220, any ideas?
Check the TC drain plug isn't leaking before going too far.
If I had to bet then I'd say the pump O Ring somehow got nicked during assembly which would require it coming out again.
After further review it appears the fluid is coming from the transmission dipstick tube o’ring above the corner of the pan. Can this o’ring be replaced without transmission removal? I think I can access the bell housing nut with a lonngggg extension. But I seem to recall another bolt on the rear of the head. Tough sledding… Opinions appreciated.
If so, that's a relief!
Yes, but it's still not a fun job. The dipstick is also bolted to the back of the head, and that bolt can be a RPITA to R&R. Otherwise, it's a straightforward job... get the corner area surgically clean, raise tube, replace O-ring (OE/Genuine only), bolt tube down.
Make SURE to tighten the lower bolt on the transmission housing first! Do not tighten the bolt at the head first. Also, if you remove the dipstick tube, you can make the head-mounting hole either oblong, or better yet completely slotted, so the hard-to-access bolt doesn't have to be fully removed in the future.
It should be replaceable by (re)moving the transmission dipstick itself, but the @gsxr would have to pass a final ruling on that. I removed the transmission dipstick on my former E320 wagon (M104 engine) when removing the transmission, and it was removable without having to remove the transmission. It bolts to the rear of the head on the M104 IIRC, and that was a serious pain in the rear to get re-threaded on there. I don't know on the E500E, but I believe the dipstick should be removeable.
I do remember that I evidently didn't get the dipstick/new o-ring quite re-installed correctly, and it was weeping from the dipstick o-ring. The poor guy I sold the E320 wagon to had to re-install/re-seat it so that it quit seeping.
I do remember that I evidently didn't get the dipstick/new o-ring quite re-installed correctly, and it was weeping from the dipstick o-ring. The poor guy I sold the E320 wagon to had to re-install/re-seat it so that it quit seeping.
Thanks for this information. Very helpful.
Dave, are we talking about bolts labeled 18 on page 105 of your file? http://www.w124performance.com/docs/mb/other/tranny_722_repair.pdf
For those bolts, I was told to use the white non-hardening sealing compound when I rebuilt mine.
BTW, every time I search something related to M119 or 722.3 on google, your page/s photos and illustrations come up
Is there any "documentation" you do not have in that "GSXR Encyclopedia" 
BTW, every time I search something related to M119 or 722.3 on google, your page/s photos and illustrations come up
Is there any "documentation" you do not have in that "GSXR Encyclopedia" So after a day and a half wrestling with the dipstick I have the new o’ring in and all three bolts tight. This was a very difficult small job. I had to cut two different Allen wrenches down to fit the tight space and use about every socket bar extension combination I had to loosen the 17mm nut without removing any exhaust pieces. GSXR’s suggestion to slot the top hole of the dipstick was crucial. It permitted me to start the top bolt and using a cut down Allen wrench I managed to get it tight. Don’t want to do that again!
