Burning Oil

[AnarchyNgine]

Hi everyone,
Got a little problem with my '93 fzj80 and I don't know where to go from here.

It's underpowered, the exhaust smells weird and it's using a lot of oil - around 1.5 litres per 500km.

It doesn't have any oil leaks and a compression test game me the following results:

1 - 185psi
2 - 180psi
3 - 190
4 - 190
5 - 190
6 - 190

These results seem pretty good for an engine that has done 370000km I think, but I can't work out where the oil is going.

If anyone can point me in the right direction it would be much appreciated.

Thanks

 

[Dirty Koala]

Valve stem seals are likely shot.

 

[AnarchyNgine]

Thanks mate. If I pull the rocker cover off, will I be able to see them and see if they're worn?

 

[scrowley]

How bad is it to drive on bad valve stem seals? I'm thinking it will dirty up the exhaust/cat, sensors, and cost a bit in oil. But I believe there is no ill effect.

 

[LFD2037]

I was using a lot of oil & it turned out to be the PCV valve. I was using ~1.5qts per 600 miles. Now I'm using <1qt per 1,000 miles.

 

[Ozdunc]

Thanks mate. If I pull the rocker cover off, will I be able to see them and see if they're worn?

No.

Get a vacuum gauge and attach it to your intake manifold somewhere, maybe the brake servo hose, that will tell you if you have leaking valves.

If you pull the rocker cover you could check the shim clearances, if they are out of spec you could be getting the symptoms you're describing.

But using the gauge would be the quickest and easiest way of diagnosing the problem

 

[AnarchyNgine]

I'll check it out, I know the valve clearances haven't been done in at least 150000km... Lol.

Would I expect the vacuum gauge to read high or low if the seals are worn?

 

[centraloregoncruiser]

I have a 92 with190k the PO did not have it long and started to put synthetic oil 5/40 in it. When I got it it was smoking while cold and burned a lot of oil and also had some leaks. I switched to 10/30 high mileage and smoking stopped and hardly burns also leaks much less. Just my .02

 

[AnarchyNgine]

Thanks for the replies fellas, I'll try some stuff out and let you know how I went. Cheers.

 

[AnarchyNgine]

Screw it. I'm just going to get a reco head for it and be done with it.

 

[LFD2037]

Screw it. I'm just going to get a reco head for it and be done with it.

And what if that doesn't fix it?

 

[AnarchyNgine]

Lol. I'll have wasted $1200 on on a head... I've replaced pretty much everything else mate. I just want this thing to run well again. :/

 

[AnarchyNgine]

I can take it to a mechanic, and I'm sure he'll find the valve clearances off their nut, worn valve stem seals and probably a burnt valve or two (or 24). I can fit a new head myself rather than pay a mechanic $2k+ to fix my head. I've pretty much replaced everything else.
I don't know what to do...

 

[AnarchyNgine]

Took it to a mechanic and he told me there was nothing wrong with it mechanically... Cost me $400.
I replaced the injectors and fixed an oxy sensor problem, and it ran really well (still a little smokey) for a day or two, until It developed another problem with the o2 sensor - see my other post. :|

Thanks for the replies fellas, at least I can count on you blokes for some good advice. Cheers.