Need some help. I have a BAD oil leak coming from somewhere on the driver side of the engine. Looks to be coming from somewhere above the oil filter but not the oil cooler (Z51). I have a scope and it seems to be coming from the area in this picture. It is not coming from the Oil Pressure switch or sender from what I can tell. What sensor is in the picture? I swear it is coming from it.

 

Ok, after more research I guess that is the oil temp sensor. I think the oil pan gasket is leaking right around that area. I can see the oil flowing behind the sensor more than from it. Hopefully changing the oil pan gasket isn't too hard?

 

best way to properly change the oil pan gasket is to remove the engine. replace the front and rear seal at the same time. you can unbolt the engine and jack it up, use a 4 piece pan gasket. However, ask any professional mechanic and most will strongly suggest using the newer style one piece rubber laminated steel core pan gasket. front and rear seals are less than 15 each last i checked. While you are in there pull the torque converter and change the pump & rear seal on the transmission. all in parts are not much, but quite labor intensive.

if the car runs good, is in good condition replacing seals and gaskets after 25+ years of service is just normal routine maintenance. labor intensive to r&r the engine and transmission, but the parts are actually very very cheap. plus it gives an opportunity for thorough cleaning of the engine compartment and undercarriage, as well as a thorough inspection of the half shafts, drive shaft, u joints etc. Believe it or not, this is part of the joy of owning an antique/classic car. doing the maintenance yourself can be fun, rewarding, and an opportunity to spend time with a child, sibling, parent, friend etc. iF YOU CAN FIND a local shop to work on it, make sure they understand it is an antique car, lines, hoses, wiring looms etc are old, brittle, and extreme care must be taken when disturbing them. If not, guaranteed it will create gremlins, intermittent drivability issues, etc.

 

That is exactly why I have the car, I like working on it myself. It is a low mileage example but old is old... LOL Man I need a lift.

 

Darn, dropping the engine for just a gasket 😫

 

Well... He said just to jack it up. This is a pretty good video I think of what is involved.

 

Does it make sense that oil would only be leaking when the engine is running if it's coming from the oil pan gasket?

 

Hey 84 wuz. Is this an 84?

Personally I would start by doing this. Grab a UV dye kit with the little flashlight and yellow glasses from amazon. Very cheap.

Now take the car to a wand wash, and personally i would take a can of that engine degreaser stuff.

You can't get under the car in the carwash obviously but you can get in there and spray that degreaser onto the base of the heads and let it run down over the block/oil pan rails. Its going to make a mess but hey you are in a carwash. I'd probably spray all around both sides, down by the k member etc. Then take the wand wash after good soak time, with as hot of water as you can get, and blast it. If it was me, i'd take a garbage bag to set down and lay on both sides of the car and spray under behind the front wheels up near the oil pan, and likely under the front air dam to clean any possible oil slick off that i could get.


I cannot think of any reason why I would pull the engine to address oil leaks other than a hole/crack in the block or head. There is no question that resealing an engine much easier, actually, downright an enjoyable experience, on an engine stand. However, if all you have leaking is/are things that are easily serviceable with engine in the car, i wouldn't rnr the engine just for oil leaks.

Without seeing your situation, i can share what i have found in order of highest frequency to least
valve cover leaks
rear china wall
oil pan gasket
rear main seal
oil pressure sender
kc4 cooler top seal leak

i've never seen any other leaks but there are ofcourse other ways.

Good luck!

 

I feel your pain. Had to do a pan gasket on my F150 4x4 and it required dropping the front axle to remove pan Wanted to mention to you that there are UV dyes made to add to engine oil. I bought a kit in the past for oil and coolant. It was great on a C3 project because the leakage had spread making it hard to find. The kit came with a UV flashlight, glasses and the dye. Fired up the car, turned on light and watched. Within a few minuets I saw this glowing liquid leaking out in the middle of a sea of black oil. Repair was still a pain but at least it confirmed I was fixing the correct spot. Good luck.

 

UV won't help. I can actually see the leak flowing behind the temp sensor... I am just surprised that it isn't leaking barely at all if any when it's not running. I am going to need to get it up and the air to get a better look I guess. For now looks like the pan at the rear some where.

 

if u can see it from the ots, why did u ask about the oil pan?

 

The leak can be seen happening behind the oil temp sensor not the oil pressure sensor. I am just surprised that it doesn't leak more when the engine is not running.

 

sry i meant ots and edited the post.

the ots is above the pan rail.

the uv dye would tell you precisely where its coming from.

i dont think the oil pan gasket has anything to do with it if the leak is at the ots.

cheers and good luck getting it sorted.

 

Engine not running, no oil pressure. No oil pressure, very little if any leak from the oil temp sensor. That sensor is under pressure when the engine is running, just like the oil pressure sensor at the rear china wall.

 

I bought this. Found leak in about 20 minutes. Most stores have them. Black light flashlights are cheap too. Saves a lot of frustration

 

So yeah, the leak is lower and behind the OTS in the picture... it's basically streaming right at the pan seal. I will see if I can get video with my scope.

 

Wow... almost a year later.... I fixed my leak today! So it was the Oil Switch! I changed the switch and the sender (the sender was already bad anyway). Took for a rip after, my God I love this car. Laid about 15 feet of rubber on my drive, ahhhh the smell of burning rubber... love it.