Chasing an oil leak

[Christien]

I just recently developed a fairly serious oil leak. The front of the passenger side heat exchanger is damp, and I'm thinking it's coming from the oil cooler right above it.

I hit it with degreaser and wiped eveything down and I'm not yet seeing any new dripping. I've circled the area that was wet in the pic. Any thoughts? Could it be something other than the oil cooler?

[thumbdoctor]

If the leak was the oil cooler you would see a leak soon after the engine is started. Look higher up because the cooling air tends to push oil leaks down from above.

[Christien]

The cooler wouldn't leak when the car's not running, would it? Or at least, would stop leaking 10 or 15 minutes after the car's off?

[Elombard]

I think the o rings where the cooler attaches to the block are a 'common' leak area IIRC?

[86911tlcab]

could also be coming from top of the engine (some common leaking points below the CIS)-very hard to see, but get a mirror and a light and try your best...and as the engine and tranny go together right near there...could be the rear main seal. Jack up the rear, clean it off really good...and fire up the engine and see if you find the source...

[CCM911]

Christien - If you spill any oil while topping off/refilling, it will flow to the rear of the engine and end up dripping down the engine oil cooler. Did you recently add oil?

I had the same thing happen, and that was the issue. My shakey hands. LOL.

[theiceman]

you call that serious ? come check out my car ..

Before you put the 3.0 in please tell me you did the trinagel of death ( thermostat oring, oil sender and cover )

[Christien]

Originally Posted by Elombard

I think the o rings where the cooler attaches to the block are a 'common' leak area IIRC?

Cleaned and checked when I transplanted the engine 18 months ago, but I've ordered new once to replace.

Originally Posted by 86911tlcab

could also be coming from top of the engine (some common leaking points below the CIS)-very hard to see, but get a mirror and a light and try your best...and as the engine and tranny go together right near there...could be the rear main seal. Jack up the rear, clean it off really good...and fire up the engine and see if you find the source...

Already checked there - nice and easy with carbs and rainhats

Originally Posted by CCM911

Christien - If you spill any oil while topping off/refilling, it will flow to the rear of the engine and end up dripping down the engine oil cooler. Did you recently add oil?

I had the same thing happen, and that was the issue. My shakey hands. LOL.

Yep, but it was way low, and checked the dipstick while adding, so not overfilled. BTDT!

Originally Posted by theiceman

you call that serious ? come check out my car ..

Before you put the 3.0 in please tell me you did the trinagel of death ( thermostat oring, oil sender and cover )

Yep, no leaks on the topside - nice and dry.

[CCM911]

Christien - I did not mean overfilled. I meant spilled. As in your pour missed the opening, and oil spilled on your engine tins. From there it will drip down onto your engine oil cooler making you think you have a leak.

[porche]

Christien,
Could you clarify a few things please?

* You cleaned the area good after discovering the leak, then restarted the engine to confirm the leak site?

* Oil only leaks when the engine is running?
* How much?

* Does it leak when the engine is off?
* How much?

[timmy2]

Next valve adjustment check the rocker shafts for leaking. Very common.

[Christien]

Originally Posted by CCM911

Christien - I did not mean overfilled. I meant spilled. As in your pour missed the opening, and oil spilled on your engine tins. From there it will drip down onto your engine oil cooler making you think you have a leak.

Ah, 1972, my friend

Originally Posted by porche

Christien,
Could you clarify a few things please?

* You cleaned the area good after discovering the leak, then restarted the engine to confirm the leak site?

* Oil only leaks when the engine is running?
* How much?

* Does it leak when the engine is off?
* How much?

Haven't restarted the engine yet. I've left it to see if it's pooling. I glanced at it this morning and nothing there from overnight, but need to check again. I won't be able to run it until tomorrow morning, so I'll check all this then.

Originally Posted by timmy2

Next valve adjustment check the rocker shafts for leaking. Very common.

It's not leaking from the valves - the covers are bone dry all along the bottom. That was the first thing I checked, as the valves were just adjusted last week.

[Christien]

Ok, this is a bit strange. Fired it up, let it run for about 5 minutes, then got underneath to have a look. I think it's the rear main seal - it's dripping from the fore end of the case, and it's a pretty bad drip:



The puddle you see at the end is about 4-5 minutes of dripping.

But that doesn't explain how the front of the right heat exchanger got oil on it, and smoked. If it's the RMS, it should just leak onto the ground and not burn off.

The oil cooler wasn't leaking at all, so that's good news. But I'll be checking the heat exchanger again after a few days of driving to see if there's another leak.

[E Sully]

When you drive the oil will be blown onto the heat exchanger.

[porche]

Looks like you've identified the source (out the hole at the end of the transaxle case and down the end of the crankcase seam). Static tests are best at identifying leaks. If you go out for a drive it begins to become a guessing game as there are a lot of different air currents in play under the car that can push the oil anywhere.

[Christien]

I cleaned the area up again and dusted it with baking soda, then ran the engine for a few minutes. I think this clears up any doubt it's the rear main seal:

[Christien]

Any other opinions, before I drop the engine and transmission to replace the seal?

[E Sully]

Seems to be the seal. Set the new seal dry, and do not set it too deep.

[enzo777]

I have same problem after change oil, And more leak , i think come from 2 tube with nuts, i try tight . Can tell liters, of oil need, when dry engine, tank, And filter? I put 7 liter, is that to much?
Regards

[thumbdoctor]

Completely drained sump and tank + filter requires about 12 quarts (11.35 liters)