Truck Smoking

[lepp1892]

So I did an oil change yesterday and today the truck is smoking really bad. It seems to be burning oil because its blue smoke and. It's a 1992 4.0... any ideas of what to check...

The oil level was also slightly high... not a lot but a little bit over the full line...

 

[MAKG]

Correct oil?

Should be 10W-30. Maybe 5W-30 if it's ridiculously cold (subzero).

 

[lepp1892]

I think i used 10W-40... it was what we had at my house... and I'm pretty sure thats was what I had used the last time i changed my oil too...

Is it really that big of deal on what oil gets used?

 

[Shran]

Oil isn't that critical, 10w40 will be fine. I'd run 5w-30 in your climate though because it's thinner.

If it's way overfull, you need to drain a little out so your crank isn't submerged.

Does it smoke all the time or just a little while? All the time could be rings, just on startup could be valve seals or something. Does it run OK other than the smoke?

 

[lepp1892]

It runs alright other then the smoke... it doesnt smoke well i am on the gas... only at idle and when i let of the gas.

 

[97ranger4x4]

is the smoke coming out of the exhaust? or out of the hood? if out of the hood, did you spill some on your motor which would cause the smoking once the engine gets hot?

 

[Shran]

I'd replace your PCV valve, and make sure you've actually got oil pressure and good compression...get your oil down to the correct level too. It might not be overfull by much but you're eliminating something.

If a couple cylinders are low on compression then it's either leaking out the valves, rings, or head gasket area. Where ever it's leaking at (if in fact it is) will probably be your problem.

 

[MAKG]

It runs alright other then the smoke... it doesnt smoke well i am on the gas... only at idle and when i let of the gas.

Assuming it's smoking out the tailpipe, these are CLASSIC signs of worn valve guides. They only smoke when there is vacuum in the intake.

The only way to fix it is a major valve job. You can try to replace the valve seals, but odds are, it will work temporarily at best.

Either that or you can give your truck a nicotine patch.

 

[lepp1892]

I'm pretty sure i blew a head gasket... i figure the blue smoke i was getting was from me cleaning the throttle body and it was just burning off all the carbon the broke loose because the blue smoke has stopped and now its basically straight white smoke... and it seems like i have some coolant in the oil...

 

[JohnPi]

I read "Truck Smoking" and I immediatly thought, "take away the cigarettes!"

Like the old children's joke: How do you stop a rhino from charging?

 

[fordktpjoe]

Like the old children's joke: How do you stop a rhino from charging?

.458 Win Mag.!

 

[JohnPi]

.458 Win Mag.!

Aaaaaaaaand THAT'S why I left the answer wide open

 

[jasonl]

I have a 96 4.0 with 194,000 miles and #6 is burning oil bad and actually will foul the plug in about 500 miles. I am assuming the valve guides are shot or could this just be the seals? Any advice on what to do? The engine purrs, and the compression seams to be fine. Would you all recommend just installing rebuilt heads or is too risky with the bottom half having so many miles? I am thinking junk yard engine and was wondering what the going rate is. I am in central PA. I am only going to put about 6,000 miles anually on this truck. Thanks for any help.

 

[dorman68]

jasonl

I recommend a good used engine form a reputable salvage source. The oil fouling could be the result of two things the first as you said a bad valve guide, head, or valve seal. The second being that the piston rings could be stuck, broken or worn and that would end up in an engine overhaul. If the rings are just stuck from carbon deposits perhaps GM goodwrench engine top end engine cleaner might help. If an engine is needed I would try LKQ online to source an used engine.

 

[jasonl]

Well I decided to tear into it today and do valve seals without removing the engine. I bought the vlave spring compressor and air hold hose from ebay. I found some pretty interesting things out about my engine. With 194,000 on it I was suprised the push rods and rockers looked fine. #6 which is where I was burning the oil, the intake seal was cracked a bit and the exhaust seal wasn't even down on the guide. It was riding half way up on the valve. I was loosing air pressure out the intake when I had the air hold hose on it which I kinda figured since the engine has been sucking oil around the valve. Cylinders 4 & 5 were sealed nice when I put the air to them. I also could not move the valves side to side so is it safe to say the guides are atleast ok?? I got it all back together and it seems the smoking is gone, I'll have to double check in the daytime to be sure. I do have a little bit of a mis at idle and low rpm cruising, I am thinking maybe low compression from the valve being gummed up. I am going to try to put some sea foam thru it and I also need to to take the egr valve off as I'm sure it's all caked up. I am keeping my fingers crossed that I have bought some time on thge engine replacement.