A&Q about 350Z
Q:
a week ago i noticed a puddle of oily liquid under the car and checking under the hood, the oil level was very low (below the low mark). checked the coolant overflow tank and noticed a light brown creamy fudge in it and the level was over the 'high' mark- so that's where the oil went?! the car was driving normally (well, it had an intermittent miss now and again but otherwise drove quite well). not having the time to do anything i emptied the creamy stuff from the overflow tank, added some coolant in it to the low mark and also added oil to the engine to the high mark.
after driving the car around over about a week (around 300 km) one night the engine was over heating (temp needle rising and nearing high mark) just before getting home. got the car home and hissing sound from under hood. when i opened the hood, noticed steam hissing out from the coolant overflow container (overflow) tube. nothing from any of the radiator pipes. was at night and figured out there's nothing i could do.
next morning i noticed a puddle of oily liquid under the car...a fairly big puddle like the first time. looking into the coolant overflow container i could see the same light brown creamy fudge way over the "high" line. looks like oil is getting into the cooling system, and sign of maybe a blown head gasket, cracked head or cylinder block, or internal damage to water/oil galleries?
checked the oil level. oil level was between low and high, oil looked ok (not light brown cream like in coolant overflow tank or evidence of any coolant. the car (3-cylinder 1992 charade) is not worth spending a lot of repair $ fixing but i want to keep using it for a few more months.
what checks do you suggest i try to isolate the problem further? i've worked on cars before and have tools including a compression tester. i rang a local shop and they mentioned $400 as a minimum just to have a look to see what the problem may be. i'm going to check out myself first, so please give me some pointers on what to check! i'm going to drain the radiator and o'flow tank of that creamy stuff and refill with water as a start point. the fact that the car ran normally (no loss in performance etc) for a week would suggest that it's not a blown head gasket? also a coolant gain (oil getting into coolant, not a coolant loss) would suggest there are no external (i checked) or internal coolant leaks into engine, but an oil leak into the cooling system?
tia.
A:
You are definitely in a pickle. In my opinion, once you noticed the puddle and fudge, you should never turned it over again until you fixed the problem. I hope that its fine, but the bad news is that there may be some extensive damage to the engine if you ran it with coolant and oil mixing.
But, let's hope for the best. You definitely have either a blown head gasket, cracked head, cracked block. Something is allowing the oil and coolant to mix. A leaking head gasket doesn't have to cause a compression leak or poor performance. It could be leaking between a coolant passage and the oil return, or it could be a crack in one of several places.
I suggest the cranking compression test, but if that doesn't show up an obvious answer, try a pressure test on the coolant system. Pull the dipstick and (don't laugh) taste the oil. DON'T swallow any of it, but we know there is oil in the coolant. If the oil tastes or smells sweet, there is coolant making it to the oil as well.
A:
mmmmm, good ol' motor oil. If it is a blown head gasket or you can't find out what it is, I'd suggest phoning around to all the local shops and asking for a price for a) a look under the hood, and b) a gasket change. It might help to post what car it is. but if it's an old car, and it's a cracked head or cracked block it might be cheaper to buy a new car. a cracked block usually means you need to replace the engine and with labor charges, the price of a new engine, etc, it could come out to be more than the car's worth.