# Motor oil leak on my 77 Nova sedan **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** chevrolet, classic\ **Created:** [March 4, 2015, 1:40am UTC](https://community.cartalk.com/t/motor-oil-leak-on-my-77-nova-sedan/89206 "2015-03-04T01:40:25Z")\ **Posts on this page:** 16\ **Page:** 1
**Author:** ![pablochacon20](https://avatars.discourse-cdn.com/v4/letter/p/45deac/32.png) [@pablochacon20](https://community.cartalk.com/u/pablochacon20)\ **Post date:** [March 4, 2015, 1:40am UTC](https://community.cartalk.com/t/motor-oil-leak-on-my-77-nova-sedan/89206/1 "2015-03-04T01:40:25Z")
My 77 Nova sedan has been leaking motor oil from where the motor and transmission meet, around the oil pan region. I have been told it is the rear main seal but I would like to get some more opinions as to what might be the cause to the leak. ---
**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\ **Post date:** [March 4, 2015, 1:44am UTC](https://community.cartalk.com/t/motor-oil-leak-on-my-77-nova-sedan/89206/2 "2015-03-04T01:44:16Z")
Most likely rear main seal. Which engine? ---
**Author:** ![MikeInNH](https://avatars.discourse-cdn.com/v4/letter/m/a587f6/32.png) [@MikeInNH](https://community.cartalk.com/u/MikeInNH)\ **Post date:** [March 4, 2015, 1:46am UTC](https://community.cartalk.com/t/motor-oil-leak-on-my-77-nova-sedan/89206/3 "2015-03-04T01:46:03Z")
Not much else in that area oil can leak from. ---
**Author:** ![pleasedodgevan2](https://avatars.discourse-cdn.com/v4/letter/p/ad7895/32.png) [@pleasedodgevan2](https://community.cartalk.com/u/pleasedodgevan2)\ **Post date:** [March 4, 2015, 2:01am UTC](https://community.cartalk.com/t/motor-oil-leak-on-my-77-nova-sedan/89206/4 "2015-03-04T02:01:09Z")
If you have a V-8 it may be leaking from the oil pressure sensor which is under the distributor sort of. You only need a flashlight to check it. ---
**Author:** ![pablochacon20](https://avatars.discourse-cdn.com/v4/letter/p/45deac/32.png) [@pablochacon20](https://community.cartalk.com/u/pablochacon20)\ **Post date:** [March 4, 2015, 2:10am UTC](https://community.cartalk.com/t/motor-oil-leak-on-my-77-nova-sedan/89206/5 "2015-03-04T02:10:02Z")
Its the 350 with the turbo trans. ---
**Author:** ![bing](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bing/32/4619_2.png) [@bing](https://community.cartalk.com/u/bing)\ **Post date:** [March 4, 2015, 2:18am UTC](https://community.cartalk.com/t/motor-oil-leak-on-my-77-nova-sedan/89206/6 "2015-03-04T02:18:58Z")
From here it looks like the rear seal but might want to have someone else take a look too. ---
**Author:** ![Rod-Knox](https://avatars.discourse-cdn.com/v4/letter/r/a183cd/32.png) [@Rod-Knox](https://community.cartalk.com/u/Rod-Knox)\ **Post date:** [March 4, 2015, 2:20am UTC](https://community.cartalk.com/t/motor-oil-leak-on-my-77-nova-sedan/89206/7 "2015-03-04T02:20:04Z")
As @pdv2 mentioned the oil sender is the most likely source of the leak. ---
**Author:** ![Barkydog](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/barkydog/32/2470_2.png) [@Barkydog](https://community.cartalk.com/u/Barkydog)\ **Post date:** [March 4, 2015, 5:02am UTC](https://community.cartalk.com/t/motor-oil-leak-on-my-77-nova-sedan/89206/8 "2015-03-04T05:02:42Z")
Seen a few rusted oil pans leaking. Verify the source before throwing parts at it. ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [March 4, 2015, 7:23am UTC](https://community.cartalk.com/t/motor-oil-leak-on-my-77-nova-sedan/89206/9 "2015-03-04T07:23:23Z")
It does sound like it might be the rear main. But it’s very hard to tell just by looking at where the oil is accumulating. There’s a massive wind force in that area as you drive down the freeway and any oil dripping from anywhere gets blown all over the place. A shop would clean the whole area up, then keep an eye on where exactly it is leaking from. They also might add a UV dye to the oil to help. ---
**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\ **Post date:** [March 4, 2015, 8:18am UTC](https://community.cartalk.com/t/motor-oil-leak-on-my-77-nova-sedan/89206/10 "2015-03-04T08:18:53Z")
If it is leaking a lot, probably oil pressure sender. Not so much but enough to make a mess is probably the rear main seal. These old 2 piece seals never really seal worth a hoot. They always seep a little bit. Drips, not puddles. I hate to say you’ll have to pull the engine to fix a rear main seal, I’m pretty sure there isn’t enough room to drop the pan with the engine in. ---
**Author:** ![ok4450](https://avatars.discourse-cdn.com/v4/letter/o/e9bcb4/32.png) [@ok4450](https://community.cartalk.com/u/ok4450)\ **Post date:** [March 4, 2015, 8:31am UTC](https://community.cartalk.com/t/motor-oil-leak-on-my-77-nova-sedan/89206/11 "2015-03-04T08:31:12Z")
If that’s the original rear main seal then by all rights it should have been leaking decades ago. Those 2 piece seals can be changed without pulling the engine but the motor mount bolts have to be removed and the engine jacked up 3 inches or so. That should allow the pan to slide out although it will probably be a snug fit. I agree with pleasedodgevan about making sure the oil pressure sender is not leaking. Many times these things seem to give up towards the end of winter due to the plastic inserts getting so brittle. ---
**Author:** ![pablochacon20](https://avatars.discourse-cdn.com/v4/letter/p/45deac/32.png) [@pablochacon20](https://community.cartalk.com/u/pablochacon20)\ **Post date:** [March 5, 2015, 12:00pm UTC](https://community.cartalk.com/t/motor-oil-leak-on-my-77-nova-sedan/89206/12 "2015-03-05T12:00:07Z")
Thanks. I checked the oil sensor and it is definitely the source. Thanks so much saved me the trouble of jacking the engine and that sort of mess. ---
**Author:** ![steph\_H011](https://avatars.discourse-cdn.com/v4/letter/s/bb73d2/32.png) [@steph\_H011](https://community.cartalk.com/u/steph_H011)\ **Post date:** [March 5, 2015, 1:14pm UTC](https://community.cartalk.com/t/motor-oil-leak-on-my-77-nova-sedan/89206/13 "2015-03-05T13:14:27Z")
leaking oil is a problem. this means that the oil is getting to the spark plugs which will slow the car down and cause starting problems as well a problems accelerating after stops. The gasket is broken or the oil retaining ring needs to be replaced. Which ever of the two or both, this takes time because you have to remove the motor,separate it from the transmission. This leak is not to take lightly. The repair has to be done ASAP because if not the engine will crack and can split the motor open. if you are unsure what to do… consult a nearby mechanic for this please ---
**Author:** ![MikeInNH](https://avatars.discourse-cdn.com/v4/letter/m/a587f6/32.png) [@MikeInNH](https://community.cartalk.com/u/MikeInNH)\ **Post date:** [March 5, 2015, 8:40pm UTC](https://community.cartalk.com/t/motor-oil-leak-on-my-77-nova-sedan/89206/14 "2015-03-05T20:40:30Z")
> **leaking oil is a problem. this means that the oil is getting to the spark plugs which will slow the car down and cause starting problems as well a problems accelerating after stops** HUH??? ---
**Author:** ![Yosemite](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/yosemite/32/643_2.png) [@Yosemite](https://community.cartalk.com/u/Yosemite)\ **Post date:** [March 5, 2015, 8:50pm UTC](https://community.cartalk.com/t/motor-oil-leak-on-my-77-nova-sedan/89206/15 "2015-03-05T20:50:41Z")
The Op already stated that it is the sending unit, where the leak is. Even if the rear main seal was leaking…there’s little chance that the leaking oil would get to the plugs and wires. Gravity!!! I don’t know why @steph_H011 would think he still may need to pull the motor and tranny apart. Change the sending unit and it’s fixed!!! Yosemite ---
**Author:** ![Caddyman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/caddyman/32/23_2.png) [@Caddyman](https://community.cartalk.com/u/Caddyman)\ **Post date:** [March 7, 2015, 12:31am UTC](https://community.cartalk.com/t/motor-oil-leak-on-my-77-nova-sedan/89206/16 "2015-03-07T00:31:37Z")
Climb up under the hood with a flashlight and look down beside the distributor for the oli pressure sender. It should be dry. If there is a puddle of oil around it, you have found your leak…