Losing oil, but where?

[Oni]

Hi, I checked my oil today and it was a little low, about the middle of the low and high marks. The car is a '90 with 190,000 k;s on the clock. the oil was changed at 187,000 with mobile 1 synthetic. ive checked under the car for leaks and also under the oil filter and havent found any, ive also not noticed any smoking. Any ideas where the oil could have gone?

[daffyflyer]

Out of the oil cap?

(sorry, that was uncalled for )

Could be burning it a bit, without that much smoke.

Also have you looked at the bottom of the engine? might be a sump gasket or something?

[Oni]

Thanks for your replies its made me feel alot less stressed. Im a novice when it comes to car matainance i only just learned to change my oil ( at 187,000 ). ive jacked the car up and had a look under where the drain plug is and its quite clean, i deliberatly cleaned that whole area when i changed the oil so i could see if i had leaks. Is that what you mean by the bottom end? sorry if this is a silly question

[daffyflyer]

Thanks for your replies its made me feel alot less stressed. Im a novice when it comes to car matainance i only just learned to change my oil ( at 187,000 ). ive jacked the car up and had a look under where the drain plug is and its quite clean, i deliberatly cleaned that whole area when i changed the oil so i could see if i had leaks. Is that what you mean by the bottom end? sorry if this is a silly question

Yep, thats pretty much what im thinking, by sump gasket, i mean the seal where the oil pan/sump on the bottom of the engine bolts to the engine, oil can leak outta there, does that make sense?

[Garry]

With 190,000km on the clock I wouldn't be surprised if it was using a bit of oil. I'm sure the rings and valve guides aren't quite as effective as they were when it left the factory.

2 other places to check for external leaks are underneath the crank angle sensor at the back of the head. It uses an O-ring seals and is notorious for leaking, especially if you have been playing with the ignition timing recently. Also check at the back underneath of the engine where the gearbox bell housing attaches. Your rear main seal could be leaking. But basically if there are no external leaks then the car is burning oil and it's going out the exhaust.

[Oni]

Thanks Daffy that does make sense, ill double check that tonight.

Garry
Thanks for the suggestions ill certainly check the back of the engine tonight ( once i clean up for my other mistake ). I havent changed the ignotion timeing but its worth checking.

Thanks again

[Fuzzlet]

Haha my NA when it had 170k kms on it used oil. After the engine was rebuilt it still used a bit of oil and blew smoke...

[daffyflyer]

Haha my NA when it had 170k kms on it used oil. After the engine was rebuilt it still used a bit of oil and blew smoke...

Yep, still uses oil, might just be a NA thing i suspect, mostly seems to leak it from the rocker cover & cam sensor i noticed.

[bruce]

Yup, I'd expect the engine to be using a little bit of oil. Perhaps change over to a slightly thicker oil as Mobil 1 may be a bit thin and getting past the rings and getting burnt.

[Lev]

I have similar K's, I was loosing it from the CAS, also rear side of the cam cover and the front main crank seal.

[93_Clubman]

Hi, I checked my oil today and it was a little low, about the middle of the low and high marks. The car is a '90 with 190,000 k;s on the clock. the oil was changed at 187,000 with mobile 1 synthetic. ive checked under the car for leaks and also under the oil filter and havent found any, ive also not noticed any smoking. Any ideas where the oil could have gone?

my previous mx5, an '89 na6 with over 180k kms, required the occasional oil top up, depending on the type of driving, even though there was no smoke. when you say you've checked under the car for leaks, do you mean you've checked the ground where you park overnight or at work for leaks? if not, this will help indentify more substantial leaks which can then be pinpointed. slower leaks won't always drip if the car is being regularly used & can just seep/blow backwards.