New engine smell???

[68Blu]

Hey guys, just dropped a new 350 in the 68, now I notice the smell of burning oil after driving for about 15 mins. There are no leaks/ puddles after driving or sitting over night. It also doesn’t appear to be the heater core as it’s also isn’t leaking and there are no melted wires. Any ideas? Thanks

[Ol Blue K20]

Are you smelling oil or paint curing and burning off?

[Willys_MB]

Did you break in the cam and change the oil before driving it?

[68Blu]

Brake in was done as per GM instructions. It’s oil.

[sick472]

PCV working correcty?

Strong oil smell under the hood or out the exhaust?

It's not belt rubber smell?

A slight leak can run onto the headers/maniflods and burn off without any drips or puddles (so can antifreeze leaks).

Is it brake fluid on the discs/drums?

Ol Blue hit on something that always takes me by surprise...when a fresh motor starts up and starts smoking the paint (or oil residues from assembly) of the manifolds.

[Willys_MB]

How many miles since you changed the oil? I recently did my first break in and had a similar issue that went away after a second oil change.

[geezer#99]

Look on the back of the intake. Could be china wall gasket or oil pressure fitting. Any leaks there don’t show up on the floor. Just coats the top of the trans and underside of the truck.

[hamjet]

Originally Posted by geezer#99

Look on the back of the intake. Could be china wall gasket or oil pressure fitting. Any leaks there don’t show up on the floor. Just coats the top of the trans and underside of the truck.

or dripping on the exhaust pipe..

[zosoppp]

it might also be leaking/seeping valve cover gaskets, especially with the older flange bolted valve covers. that would leak out onto the manifolds and burn and likely not make it to the floor for quite a while.

[bigmac73]

Best thing is dust with baby powder and run engine and see if you see a wet spot or oil trail

[68Blu]

Thanks guys! I will checking all of these things in the coming days and will keep you posted ��

[fdbdw]

Did you by chance put in any new exhaust parts?I have had burning smell from new mufflers and headers in the past. Sometimes they are coated with an oil for storage , then it burns off in the first couple warm ups.

[68Blu]

Well, guys the mystery continues. I checked your recommendations and nothing. Thanks again

[Steeveedee]

Originally Posted by 68Blu

Well, guys the mystery continues. I checked your recommendations and nothing. Thanks again

Central coast- are you around Ventura somewhere thereabouts? Maybe there's somebody that could come by and take a look-see. Plenty of board members in California. Just saying. I'm about 40 miles from you. Maybe I can make an excuse to go to a store in Ventura if I can evade the popo.

[bcfishon]

Has to be an external leak somewhere,i would drive it till it smells and pull into dark shop with flashlight to inspect,smoke shows up better in the dark. Only so many places it could leak,intake,distributor,valvecovers,fuelpump,oil pressure,timing chain/oil pan or the rear seal,God forbid you have a leaky oil galley plug.

[geezer#99]

Could be internal too.
Poorly installed intake gasket that’s not sealing and oil is being pulled up from the lifter valley.

[Corts60]

If you can't find any external leaks, pull plugs and look to see if any cylinders are oil soaked. If you find one, perform a leak down test of that cylinder to see what exactly failed.

[68Blu]

I’m not getting emails from this site anymore, sorry for the late response. I’ll try to start checking in more. I’m actually over 1.5 hours from Ventura, Steeveedee- thanks for the offer though. I’ll keep looking and try your suggestions but it may be a week or 2... Thanks again everyone.

[bcfishon]

I would think a internal leak would let stink go out the tailpipe unless you have some serious exhaust leakage but one never knows how another rig blows. Do not forget it takes a little bit for new rings to seat and sometimes especially with high oil pressure systems oil can make it past the rings and give off a unburnt petroleum smell from the exhaust stroke,I love that smell but this sounds different,good luck.

[68Blu]

Found it. Not the engine but the transmission. New tranny and we’re off. Thanks everyone for the suggestions.

[Stocker]

Sure didn't see that one coming! Glad you found it & got it fixed!

[BigBird05]

Just before you posted the trans, I was thinking vacuum modulator. It doesn't happen often, but when it does, it's hard to find.