Pondering about oil leak...

[wwdwgs]

'87 944s (98K mi):
An oil leak appears after driving. When parked for 30 min or so there's a small pool of oil about 2-3 inch in diameter. Drips from lowest point of oil pan. Oil all over an engine and hot.
When cold and parked overnight, there are only few drops. Oil is in the pan and cold.
Oil level on dipstick is about 1/3-1/2 from low mark up.
I don't know the normal oil level, when it's all drained into the pan - above oil pan gasket or below.
I didn't inspect the underside yet and can't tell where the leak(s) come from.
Does anyone have any thoughts about why it leak more when hot?
I know that it's "better to change all gaskets, seals and o-rings".
My goal is to figure out where the leak is and try to "fix" it (to keep driveway clean), and, later, do a proper "fix" like front-end seals, AOS, intake gaskets, cam chain guides, hoses, etc.
What do you think?

[SilverLined]

Originally Posted by wwdwgs

I know that it's "better to change all gaskets, seals and o-rings".
My goal is to figure out where the leak is and try to "fix" it (to keep driveway clean), and, later, do a proper "fix" like front-end seals, AOS, intake gaskets, cam chain guides, hoses, etc.
What do you think?

To fix it, without fixing it? Layer cardboard on the driveway.

You can't fix something if you don't know what the issue is. Finding the problem (likely a front-of-engine seal, but could be ANYTHING) means taking things apart, which is a big part of the job of fixing... so, once you start removing things, it only makes sense to put it back together with new bits that won't leak or worse. Ignore leaks at your peril; a slippery belt can be really, really expensive.

I'd recommend to keep it off the road until you're ready to do the work. When you are, do it all and do it right, once.

[walfreyydo]

You should start by cleaning every possible area on the engine that is showing signs of oil leakage. Brake cleaner (with a pan below to catch), a soft bristle brush and a ton of towels is what I did.

Once that is done drive the car and identify where you see oil leaking. Identify the (probably many) areas/seals where oil is leaking. UV oil dye also helps.

Keep in mind that most of these cars usually need an entire engine reseal if it hasnt been done. That includes all the front balance shaft seals/sleeves, oil pump, oil pump drive gear, front main seal, oil pan, rear main seal, balance shaft housing seals, rear balance shaft seals, front/rear cam seal, AOS seal.

Determining where the oil is leaking can help you narrow down what seals are leaking so you can potentially avoid the difficult to reach/replace ones (like rear cam seal or balance shaft housing seals, rear main and oil pan).

Speaking from personal experience, I found that my car needed almost every seal. I was able to avoid having to do the balance shaft housing and rear balance shaft seals, but had to replace everything else.

[wwdwgs]

walfreyydo,
Yes, I think that all ("all") seals need to be replaced. eventually.
I did think about adding a fluorescent dye in oil, run it and check "leaks" with UV light.
My intention was to stop this pesky oil leak - so I can stop placing cardboard boxes on the floor and start on slow and painless work....

[TibetanT]

Hello There:

Not trying to upset anyone, but a 944 should not leak oil, period !!

If you have oil in the car when checking it should be at the top mark. Top mark is where it is for the length of the oil service period; in my case I replace oil every 3,000/4,000 miles.

If the oil mark does not stay at the TOP of the dip stick, then you should NOT DRIVE the car.

Is this the 87 944S you purchased recently? Was there any records with the car when you bought it?

IF YOU purchased the car without any records of the car's maintenance schedule, my advise is:
1) Do not drive the car
2) Begin servicing the car as if you are at the 50,000 mile maintenance.
3) Get a PPI done by someone who knows these cars....actually, this should be NUMBER 1 on this list of things....IMHO

I am no expert, but I have restored/maintained these 944s for a while now. They are wonderful cars and fun to drive.

Good luck

[OK-944]

It can be hugely satisfying/rewarding to go ahead and drop the engine on these cars and take them apart. I've done two of these engines so far, and if I woke up tomorrow to be greeted by a shopful of needy 944 engines...I'd be a happy man for sure!

[wwdwgs]

TibetianT,
No records - so, I assume that the car needs maintenance like seals/gaskets, bushings, liquids. weatherstripping (roof/hatch/doors) and cleaning/lubricating. The only verifiable repair was is the timing belt 4000 miles ago. Knowing that PO acquired this car about 7.5 years ago, TB can be replaced, too.
I don't drive it - it sits patiently on driveway for its turn for repairs.

OK-944. in my experience it's easier to "drop" an engine in 911/912/914 cars. )

[walfreyydo]

Originally Posted by TibetanT

Hello There:

Not trying to upset anyone, but a 944 should not leak oil, period !!

Completely whole heartedly agree. My 944 doesnt leak a drop of oil anymore and its an incredibly satisfying feeling. It came at the cost of many hours and replacement of (almost) every seal on the engine, including the dreaded rear main seal, which I tackled along with a clutch replacement and torque tube bearing replacement.

The front seals are where you should start, and should accompany a timing and balance belt/roller service. Upper and lower balance shaft seals and shaft sleeve, along with oil pump to block reseal, front main seal and oil pump drive gear are where I started (year 1). I also replaced the oil cooler housing seal and oil pressure sender crush washer as well.

The winter of year 1/year 2 I tackled the oil pan gasket (re-installation not as easy as one would think) and did rod bearings and engine mounts while I was in there. I also replaced the Air Oil Separator upper and lower o-rings (also leaking when I added oil).

Summer of year two I was still getting oil leak and was confirmed to be rear main seal (since all other possible seal leaks from that area had been addressed). Although the leak was moderate, it was something that could be delayed but not ignored.

Winter of year 2/year 3 was the big job of clutch/RMS/torque tube rebuild. Since its a large job I took my time and worked on it little by little. Overall, when spaced out piecemeal, it wasnt terrible and I was able to get the car back together by spring.

Since then I havent had 1 drop of oil leak, and have an extremely clean engine/underbody to boot. Everything looks brand new, but it took a lot of elbow grease to get there. In hindsight pulling the motor probably would have made the seal replacement much easier but it would have meant taking the car out of commission - and I wanted to be able to do the seals piecemeal so I could continue to drive the car during spring/summer/fall.

Although I have made a lot of progress, the "to do" list on my car remains long (as it does for all of us I am sure)- to me thats part of the journey and fixing the car myself gives me enormous satisfaction. The car is super reliable now and I have much more confidence taking it on longer drives and to autox events without a trailer (although thats going to bite me one of these days Im sure).