New engine smell??? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

68Blu · 04-28-2020, 01:18 PM

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** · 04-28-2020, 01:24 PM

Are you smelling oil or paint curing and burning off?

Willys_MB · 04-28-2020, 01:46 PM

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

68Blu · 04-28-2020, 02:44 PM

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

sick472 · 04-28-2020, 02:56 PM

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 · 04-28-2020, 02:58 PM

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 · 04-28-2020, 02:59 PM

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 · 04-28-2020, 03:02 PM

Quote:

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 · 04-28-2020, 04:08 PM

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** · 04-29-2020, 07:48 PM

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

68Blu · 04-30-2020, 11:56 AM

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

fdbdw · 05-01-2020, 09:13 AM

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 · 05-04-2020, 09:14 PM

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

**Steeveedee** · 05-04-2020, 10:49 PM

Quote:

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 · 05-05-2020, 12:21 AM

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 · 05-05-2020, 12:42 AM

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

**Corts60** · 05-05-2020, 09:11 PM

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 · 05-06-2020, 09:07 PM

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 · 05-08-2020, 05:29 PM

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 · 06-17-2020, 10:39 PM

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

**Stocker** · 06-18-2020, 12:22 AM

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

BigBird05 · 06-18-2020, 09:09 AM

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.

04-28-2020, 01:18 PM	#1
68Blu Registered User Join Date: Jun 2019 Location: California Central Coast Posts: 82	New engine smell??? 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

04-28-2020, 01:24 PM	#2
Ol Blue K20 Proprietor of Dale's Corner Join Date: Nov 2012 Location: Vacaville , CA Posts: 16,245	Re: New engine smell??? Are you smelling oil or paint curing and burning off? __________________ "Some Days Chickens And Some Days Feathers" Dale XNGH ECV Sam Brannan 1004 R.I.P. 67ChevyRedneck R.I.P. Grumpy Old Man R.I.P. FleetsidePaul

04-28-2020, 01:46 PM	#3
Willys_MB Registered User Join Date: Apr 2017 Location: Boise, ID Posts: 856	Re: New engine smell??? Did you break in the cam and change the oil before driving it? __________________ 1968 GMC C2500 Long Bed Fleetside

04-28-2020, 02:44 PM	#4
68Blu Registered User Join Date: Jun 2019 Location: California Central Coast Posts: 82	Re: New engine smell??? Brake in was done as per GM instructions. It’s oil.

04-28-2020, 02:56 PM	#5
sick472 Registered User Join Date: Jul 2015 Location: Sedalia Mo. Posts: 1,131	Re: New engine smell??? 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. __________________ He who is without oil shall throw the first rod. Compressions 8.7:1 1972 C10 1976 C10 (parts truck) 1985 K20

04-28-2020, 02:58 PM	#6
Willys_MB Registered User Join Date: Apr 2017 Location: Boise, ID Posts: 856	Re: New engine smell??? 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. __________________ 1968 GMC C2500 Long Bed Fleetside

04-28-2020, 02:59 PM	#7
geezer#99 Registered User Join Date: Aug 2009 Location: Bowser Posts: 13,731	Re: New engine smell??? 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.

04-28-2020, 04:08 PM	#9
zosoppp Registered User Join Date: Mar 2014 Location: Lincoln Park, NJ Posts: 190	Re: New engine smell??? 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. __________________ 1970 C10 LWB 350SBC, SM330 Muncie (not saginaw SM326) (on tree), 3.07 open (assumed), PS, PB, Idiot lights

04-29-2020, 07:48 PM	#10
bigmac73 Senior Member Join Date: Mar 2012 Location: Chesapeake, Va Posts: 1,275	Re: New engine smell??? Best thing is dust with baby powder and run engine and see if you see a wet spot or oil trail __________________ Mike 72 C-10 Cheyenne off frame resto and Upgraded to 4 wheel disk, Tilt, Dakota Digital Dash / Rear slider. 421 SBC / TH350 3000RPM Stall Progression Ignition /Holley 750 DP/3:73 gear Eaton Limited Slip unit / 2 1/2 exhaust glasspacks

04-30-2020, 11:56 AM	#11
68Blu Registered User Join Date: Jun 2019 Location: California Central Coast Posts: 82	Re: New engine smell??? Thanks guys! I will checking all of these things in the coming days and will keep you posted ��

05-01-2020, 09:13 AM	#12
fdbdw Registered User Join Date: Jan 2009 Location: colorado springs Posts: 479	Re: New engine smell??? 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.

05-04-2020, 09:14 PM	#13
68Blu Registered User Join Date: Jun 2019 Location: California Central Coast Posts: 82	Re: New engine smell??? Well, guys the mystery continues. I checked your recommendations and nothing. Thanks again

05-05-2020, 12:21 AM	#15
bcfishon Registered User Join Date: Nov 2012 Location: canby,oregon Posts: 356	Re: New engine smell??? 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.

05-05-2020, 12:42 AM	#16
geezer#99 Registered User Join Date: Aug 2009 Location: Bowser Posts: 13,731	Re: New engine smell??? Could be internal too. Poorly installed intake gasket that’s not sealing and oil is being pulled up from the lifter valley.

05-05-2020, 09:11 PM	#17
Corts60 Just here to tinker Join Date: Jun 2008 Location: Holland, MI Posts: 3,697	Re: New engine smell??? 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. __________________ 78 C10 SWB Diesel #1 (wrecked)http://67-72chevytrucks.com/vboard/s...1978+silverado 78 C10 SWB Diesel #2 (sold)http://67-72chevytrucks.com/vboard/s...d.php?t=650751 60 GMC Suburban (sold)http://67-72chevytrucks.com/vboard/s...d.php?t=445526 60 GMC 1000 (sold)http://67-72chevytrucks.com/vboard/showthread.php?t=298235 67 GMC 1500 (sold) http://67-72chevytrucks.com/vboard/s...d.php?t=803695 73 Chevy C20(Daily)http://67-72chevytrucks.com/vboard/s...d.php?t=852767 86 Suburban(summer unit) http://67-72chevytrucks.com/vboard/s...d.php?t=810697 88 Suburban 4x4(sold)



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05-06-2020, 09:07 PM	#18
68Blu Registered User Join Date: Jun 2019 Location: California Central Coast Posts: 82	Re: New engine smell??? 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.

05-08-2020, 05:29 PM	#19
bcfishon Registered User Join Date: Nov 2012 Location: canby,oregon Posts: 356	Re: New engine smell??? 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.

06-17-2020, 10:39 PM	#20
68Blu Registered User Join Date: Jun 2019 Location: California Central Coast Posts: 82	Re: New engine smell??? Found it. Not the engine but the transmission. New tranny and we’re off. Thanks everyone for the suggestions.

06-18-2020, 12:22 AM	#21
Stocker 20' Daredevil (Ret) Join Date: May 2003 Location: Jefferson State Posts: 13,722	Re: New engine smell??? Sure didn't see that one coming! Glad you found it & got it fixed! __________________ - Mike - 1972 K20 LWB 350/350/205 RIP El Jay

06-18-2020, 09:09 AM	#22
BigBird05 Registered User Join Date: Aug 2019 Location: Cheraw Posts: 1,300	Re: New engine smell??? 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.

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