3.4 smoking but not running hot

I was working on my winch control box relocation today when I noticed some faint smoke coming from between the valve covers and behind the engine on the driver side. I have have noticed a burning smell ever since I’ve owned the truck which I thought was rubber (but may be burning oil?). I’m hoping it’s leaking valve cover gaskets that’s causing oil to drip on hot parts of the engine and burn off and nothing more serious. Truck runs fine and it’s running hot or anything according to my scanguage. Here’s a video of the smoke: https://youtu.be/1wrWRuVgQ9w

 

oil has a distinctive smell as does anti freeze. Leaking around the valve covers is not uncommon with the D/S being the difficult side to do. With all of the proper parts this is a saturday moring/done by noon project... lots of videos out there on doing it. If it is coolant my first suspect are the coolant lines that go to the IAC valve.

 

I guess I’m going to have to burn a little of both to smell the difference

 

On second thought, I think it may be oil. Just looked under the truck and noticed a few drops on the ground

 

Yeah the other thing that it might be if it's an oil leak is just loose 10 mm nuts that secure the valve covers. I just did mine and found that they were SUPER loose which made me wonder if my leak wasnt so much bad valve cover gaskets as it was loose valve covers.

 

To be honest I wouldn’t worry about it, i just did my valve covers because they leaked and usually it would smoke in the engine bay just from the little bit of oil dripping onto the exhaust manifold.

That being said, check around your valve covers to see if they are leaking, if so try looking on your exhaust manifold for any wet spots or while running look and try to see if any smoke is coming off of the exhaust manifold.

Coolant smells slightly sweet when burned and oil smells Kinda burnt. If you can describe what you smell I’m sure someone on here could help figure it out

 

like everyone else said. Looks like your valve cover seals leaking or to be exact the half-moon in the back might be leaking. valve cover seals usually go bad after 150k miles. the sealant and seals just go bad after time. If you have an inspection mirror. Put it on the back right and see if you see any oil seeping through. Timmy the toolman has some great videos and one on this project specifically.

 

Do you drive the truck regularly? If you do and you still get a good amount of smoke each time you start driving it might be worth fixing, can you notice on the dipstick How much oil you’re losing? I would also assume valve cover gaskets, if you see oil coming from between engine and trans it could also be rear main seal.

 

I've been driving it more lately. It's not a daily driver so the amount I drive it varies. She's about to go down for a while now that hunting season is over. I'm going to do an ARB bumper/ Smittybilt X20 install, E locker rear end swap + AAL and U bolt flip, CV axle replacement.. may as well just knock out the valve covers too if that seems to be an issue. I'm going to try tightening the bolts first to see if that does anything.

 

Yea my truck sits from time to time and I get a little smoke when I first start it up from a slow leak in the valve cover gasket but if I drive it regularly it doesn’t have time to let oil buildup. If I check the dipstick the amount of oil lost is negligible.

 

Be careful with this.

My 2003 FSM says the torque spec for the 8 valve cover bolts is 53 inch lbs. (not ft. lbs.). If you are counting, that isn't very much, barley more than finger tight.

 

Will do

 

99 percent its the valve cover gaskets half moon.
It’s very easy to just get a flashlight and get up in there and look on both sides. It will be obvious

 

The gaskets were still bad. They start out fat and squishy and then shrink over time, allows the bolts to feel like they've backed off

 

Tighten the valve covers down, if that doesn’t fix it, I’d ask if you are running synthetic oil, it will leak more easily on older vehicles in my experience. I run synthetic in my newer vehicles, I love the stuff, but some of my old vehicles will leak when I use it.

 

Thanks for helping me justify the time and money spent. Either way it gave me peace of mind just to get it done.

 

I've been researching the job and just found your thread on the tesa tape. I think I'm going to do the same thing. What size split loom did you use?

 

Just for the sake of saying it, I actually never put the tesa tape on and kept the electrical tape to see what would happen. I've put about 1k miles on it since then and checked the other day- hasn't melted at all. So I figure I'll check back later to see if the tesa tape is actually needed. Thus far, the electrical tape is holding up like a champ.

The loom I used was easy loom split line sleeving which was 1/2" in diameter. I had to double up on the driver's side since there is a lot more wiring on that side. The easy loom made doubling up pretty easy to do, you might have a trickier time doing it with typical wiring loom. It's hard to overstate how easy it was to get the valve covers off after replacing that plastic with loom. I highly recommend it.

 

I started the Tesa tape info here, IT DEFINITELY worth the few dollars and you won’t regret it.
the wire loom gets very hot in those head valleys,

I’ve put probably 50,000 miles since then and it looks perfect still.

The Tesa wiring harness tape is one of the best heat resistant 300 degrees ratings tapes available.
“Tesa 51026“

Product description
Product Features tesa® 51026 is a PET cloth wire harness tape with an acrylic adhesive. Major Features: High temperature resistance 150°C/3000h
(300 degrees) High abrasion resistance Color: Black Main Applications tesa® 51026 is designed for the engine compartment, providing high abrasion protection.

A comparison is black electric tape is rated at 180 degrees compared to Tesa heat resistant tape at 300 degrees. Tesa tape is NOT used for electrical purposes.

 

what size split tubing did you use?