Is blue smoke an urgent problem? (1 Viewer)

[MikePL]

I am about to make a 5000 mile trip in a week or two. I have had blue smoke coming out of the exhaust for a long time. Either it's worn valve seals or PCV stuff obviously.

1. But is it a problem which will cause instant ka-boom within a few thousand miles or is it just a nuisance which I can 'cure' sooner or later if I prefer?

2. I am sure that my PCV system is toast but what happens if I plug the intake part of the PCV and redirect both hoses from the valve cover to a catch can, coca-cola can or anywhere else?

I just want to make sure the engine makes the 5K-mile trip and then I don't care.

 

[94SRUNNER]

Is the blue smoke on start up or all of the time?

I get it on start up, but not consistently. In the winter and cooler temps it seems to happen more frequently. I monitor the oil and try not to worry about it. As in my case it is very likely the valve seals are wearing out. Truck runs like a champ otherwise.

 

[Mixelplix]

Usually not a short term problem.

Here's the deal with oil in the combustion chambers: Oil dramatically reduces the octane of gas. What that means in practice is that it increases the chance of ping or knock.

If you take it easy and the oil consumption doesn't increase, then you could go quite some time without an issue. If you're towing a trailer at 6500', then there may be some long term effects.

Your PCV could play a part in the smoke.

 

[MikePL]

I am aware that smoke during startup happens to be quite common and it appears more visible because of condesation in colder weather. I have smoke most of the time when I revv the engine and probably while driving too but it's not noticeable unless you really look for it (truck stopped and around 3000rpm or during startup).

OK, so first question solved: it is not an urgent problem which will send my engine south.

And what about the PCV stuff? What if I disconnect it and plug the intake part?

 

[dannyp]

you cant disconnect the hose all together. its part of the vacuum lines. whats common though is adding an inline catch can. mine is for an air compressor to catch moisture but I took all the screen filter out of the catch can so its just an open can with a line in and a line out at the top and the oil settles into the can and I just empty it when I change the oil.

 

[dannyp]

Here is mine.

 

[MikePL]

OK, and what about the hose on the left side? What does it do and does it need a catch can as well?

 

[Kernal]

MikePL: what brand/weight of oil are you using, how much oil is the engine burning, got compression test results, and have you tried a different oil to see if it made a difference??

 

[dannyp]

the one on the left is also a vacuum line( I wouldn't think you could delete it) if you take the air intake hose off you can see into the throttle body. if you have quite a bit of oil in there you can add a catch can to it as well but I haven't seen any on my truck so I never did it.

 

[MikePL]

I use an almost no-name brand, Gulf. 10W-40. No need for anything better, it's a Land Cruiser.
Engine burns around 1qt per 1500-2000 miles. But much of it drips due to a leaking valve cover gasket and the torn thick PCV hose. No worries, it's a Land Cruiser.
No compression test, engine runs fine on 35's, it's a Land Cruiser.
Will not try any different oil. No need to throw money at the vehicle, it's a Land Cruiser.

 

[rubicondon53]

The previous owner was using Mobil I 5w40 and it was going through a quart every 1,000 miles.. I switched to Delo 15w40 @ $12 a gallon and cut the consumption in half.. and the cruzer loves it.. 14.5mpgs on trips now instead of 12.5..


...via IH8MUD app

 

[Howard705]

Can't be much smoke at that little consumption with leaks. Smell it too. May not be oil.

 

[mikedamageinc]

You should fix the torn PCV hose, if it's leaking then you're losing vacuum and some responsiveness. While you're at it, add a oil catch can and you're engine will run better from less oil in the CC, effectively raises the octane. The air compressor filter menioned above is cheap and works but fills up too fast in my exp. Get a ebay one and just make sure it is sealed, I also put a brillo pad in mine to help trap oil. They go for about 20 bucks or so and will hold enough to last between oil changes. I also use tranny line for the hoses, they seem to last longer. You definitely don't want to delete the PCV system, the engine runs better with it. BTW the line without the filter in above pic is the clean side, no need for a filter, the hose is 1/2" and the dirty side is 3/8".

As far as the oil, try something a little thicker, 10w-40, 20w-50

 

[BILT4ME]

If the blue gray smoke is happening under start-up, it is typically valve guides/seals. Smoke under acceleration is rings. Watch it during deceleration as well, that can also be valve guides.