# Front main seal still leakinh **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** chevrolet, transmissions, impala, oil, engines\ **Created:** [July 5, 2020, 4:38am UTC](https://community.cartalk.com/t/front-main-seal-still-leakinh/166849 "2020-07-05T04:38:26Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![Suzanne-22](https://avatars.discourse-cdn.com/v4/letter/s/48db29/32.png) [@Suzanne-22](https://community.cartalk.com/u/Suzanne-22)\ **Post date:** [July 5, 2020, 4:38am UTC](https://community.cartalk.com/t/front-main-seal-still-leakinh/166849/1 "2020-07-05T04:38:26Z")
So i just replaces my front main seal due to.a oil leak. I noticed that i still have a leak after installing the new seal. Im pretty amiture at mechanics. But i am learning i followed YouTube all the way. I know I did the job correct. What could I be missing. Was there something I should have checked. The videos did not mention. Another possibility ---
**Author:** ![pleasedodgevan2](https://avatars.discourse-cdn.com/v4/letter/p/ad7895/32.png) [@pleasedodgevan2](https://community.cartalk.com/u/pleasedodgevan2)\ **Post date:** [July 5, 2020, 5:18am UTC](https://community.cartalk.com/t/front-main-seal-still-leakinh/166849/2 "2020-07-05T05:18:43Z")
Year, model and engine would be a big help. Leaks as well as other problems can be talked about if we know what particular thing we’re discussing. ---
**Author:** ![bcohen2010](https://avatars.discourse-cdn.com/v4/letter/b/779978/32.png) [@bcohen2010](https://community.cartalk.com/u/bcohen2010)\ **Post date:** [July 5, 2020, 7:53am UTC](https://community.cartalk.com/t/front-main-seal-still-leakinh/166849/3 "2020-07-05T07:53:46Z")
Often times, it isn’t just the seal itself which is bad–the old seal has dug a groove into the mating surface of the crankshaft. If this is deep enough, a new seal will continue to leak. Hopefully, replacing the seal alone will at least reduce the oil leak to a manageable level. ---
**Author:** ![oldtimer-11](https://avatars.discourse-cdn.com/v4/letter/o/e79b87/32.png) [@oldtimer-11](https://community.cartalk.com/u/oldtimer-11)\ **Post date:** [July 5, 2020, 3:34pm UTC](https://community.cartalk.com/t/front-main-seal-still-leakinh/166849/4 "2020-07-05T15:34:42Z")
You could have nicked the new seal with the end of the crankshaft when putting the transmission in or the crankshaft may be worn as bcohen2010 said. You can try transmission stop leak which may swell the new seal. I have seen mentioned a sleeve for the crankshaft but I don’t know what is involved in installing it or if it requires a different seal. How many mikes on this engine? ---
**Author:** ![db4690](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/db4690/32/2583_2.png) [@db4690](https://community.cartalk.com/u/db4690)\ **Post date:** [July 5, 2020, 4:07pm UTC](https://community.cartalk.com/t/front-main-seal-still-leakinh/166849/5 "2020-07-05T16:07:22Z")
What about a groove on the balancer . . . ?! ---
**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\ **Post date:** [July 5, 2020, 6:26pm UTC](https://community.cartalk.com/t/front-main-seal-still-leakinh/166849/6 "2020-07-05T18:26:52Z")
You may want to try installing an offset crankshaft seal. **An optional design available for several Chevrolet engines has an offset sealing lip. This can be used when the point of contact of the previous seal has worn a groove into the crankshaft sealing surface. The offset lip contacts the shaft at a different point than the original equipment seal, preventing oil leaking through the groove and eliminating the need for expensive crankshaft repair or replacement.** FEL-PRO sells them. Tester ---
**Author:** ![ok4450](https://avatars.discourse-cdn.com/v4/letter/o/e9bcb4/32.png) [@ok4450](https://community.cartalk.com/u/ok4450)\ **Post date:** [July 5, 2020, 7:16pm UTC](https://community.cartalk.com/t/front-main-seal-still-leakinh/166849/7 "2020-07-05T19:16:09Z")
If the harmonic balancer has a wear groove in it then a new seal will leak also. That is when these items are needed. You may need to redo this job to stop the leak. > **[Redi-Sleeves | The Timken Company](https://www.timken.com/products/timken-mechanical-power-transmission-products/seals/redi-sleeves/)** > > Timken Redi-Sleeves® provide a fast, inexpensive repair option for grooved or worn shafts and are designed to be pressed onto a shaft for enhanced sealing. View full product details. ---
**Author:** ![db4690](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/db4690/32/2583_2.png) [@db4690](https://community.cartalk.com/u/db4690)\ **Post date:** [July 5, 2020, 7:49pm UTC](https://community.cartalk.com/t/front-main-seal-still-leakinh/166849/8 "2020-07-05T19:49:06Z")
> [@ok4450](#): > > If the harmonic balancer has a wear groove in it then a new seal will leak also. A wear groove on the harmonic balancer is fairly common, in my experience ---
**Author:** ![oldtimer-11](https://avatars.discourse-cdn.com/v4/letter/o/e79b87/32.png) [@oldtimer-11](https://community.cartalk.com/u/oldtimer-11)\ **Post date:** [July 5, 2020, 10:35pm UTC](https://community.cartalk.com/t/front-main-seal-still-leakinh/166849/9 "2020-07-05T22:35:52Z")
You just heard from 3 of the most knowledgeable posters on the site. Hint; I am not one of them, no DIY does enough work to gain the experience of a good pro.