celica huge smoke coming from the back

[wara]

hi, im really worried and stressed here, seeking advice.

i recently bought celica 94, when the dashboard indicated that it need engine oil, so i bought 4 litres of shell engine oil for normal engine. i put all 4 litres into the engine. the next day, when i started the car and drove for about 1 kilometre. there were huge amount of bluish smoke coming out, i really got scared. so i parked the car on the street.

where should i do? does it mean the engine is useless?

[Keisari]

Hey there wara,

I'm sorry to have to give you the bad news... When you're blowing blue smoke like that, it's a sure sign that the engine is burning loads of oil. All engines burn a little, but this excessive burning is pretty much certainly going to involve either badly worn piston rings or valve seals, or both. (I guess it's also possible that you over-filled it, but I have a '91 5sfe engine that I fill with about 4 litres when I change the oil. Though as far as I know, most oil usually comes in 1L and 5-6L? Are you sure you didn't put 5L in it?)

What can you do about it? Well, not much without a rebuild unfortunately. You need to decide whether to rebuild the existing engine or get a new one.

The good (sort of) news is that the engine may not be useless. If it's only puffing blue smoke when you start it and have only run it for a little while (few kilometres), then it's likely just some worn valve seals. You can continue to use it for a while, although it won't be nice for the environment or other motorists. However, you will certainly need to replace your spark plugs much more often, and your O2 sensor and catalytic converter won't be happy about it. You'll consequently lose power.

On the other hand, if the piston rings are gone as well, then it's pretty much buggered and you need to rebuild. How many K's does it have? Most of these engines seem to last over 350,000K. If it's only done about 200, it might not have been very well looked after.

Either way, you can probably go and pick it up and drive it home :)

[wara]

the engine has done 180 000. the car was running fine before i added the oil. do u think its jsut that i have overfilled the engine oil?

[Keisari]

It might be, although I'm not sure if blowing huge smoke is a consequence of overfilling. I just remembered that you said you filled the oil when you had the oil pressure light. That means you probably still had SOME oil in there. Putting another 4L in would definitely overfill it (since I put 4L in after completely draining it and putting on another oil filter). I do know that overfilling will increase the pressure in the crankcase (and eventually weaken the front and rear main oil seals). This pressure increase MIGHT cause more oil to enter the combusion.

I guess the best way to check it would be to pop the bonnet and look at the dipstick. Do it while the car is level, the engine is COLD and has not been run for some time (at least 4 hours or so. Preferably overnight). Pull it out, wipe it clean, note the 'full' mark. Put it back in, take it back out and look at it very quickly (ie: before it starts to run. This is going to be difficult because you just put new oil in and it will look very clear, but I find it helps to use a tissue and 'run' it up the dipstick. When the tissue suddenly gets really oily, take the reading about there).

That engine should be fine at 180,000k unless it's been seriously abused. Good luck! I hope that's all it is, and if it is, I'm sorry for having scared you about the engine! hehe :)

edit: also, if you did overfill it, you'll need to drain all the oil and either put it back in (make sure you have a very clean container to put it in) or get some more. I don't know if you know how to drain oil, but I'll post a rough guide here anyway. To drain it, you'll need a 13mm socket (I'm fairly sure that's the one... bring a few :P), a clean* (*if you plan on re-using the oil) oil pan to collect the oil and a clean* container of some sort to transfer it into (ie: handycan).

Slide under the car. Have a look around at all the bolts you can see under the engine. You're looking for one in particular - it's on its own, is on a slight angle and is embedded into what looks like a black metal box (it stands out fairly well. you'll know when you see it). You need to put the oil pan under that bolt and undo it. When it's off, the oil should come gushing out. If you take the oil cap off, it will drain faster. When it's only slowly dripping, take the oil pan away and put a rag under the dripping. Drain the oil into the container but DON'T lose the bolt! You need to put this back before you put the oil back in. Then, put it back in (do it over 1/2hr or so, constantly checking how much is in by the dipstick and waiting a few minutes between readings).

Edited June 7, 2008 by Keisari