Hot Oil Smell

[BB767]

This is more motor specific than car related but perhaps someone has had the same thing happen.

On firm acceleration there is an immediate hot oil smell in the cockpit. When the gas pedal is released the smell is instantly gone.

I am not talking about wheel spinning drag racing acceleration, just accelerating on an uphill freeway on ramp, or passing on a two lane road.

There is absolutely NO sign of oil escaping anywhere on the car! Engine is squeaky clean, oil cap is tight and properly vented, PCV valve is clean and vent tube is firm and in place, not a drop of oil on or under the engine, no sign of foam or mist escaping anywhere! Very mysterious. I am not really worried about it since I am not loosing or ejecting any oil, just curious.

Just wondering if anyone else has had this happen and what is it from?

[Higgybulin]

I was going to say PCV breather, and to switch it side to side so it was at the opposite end of the motor. But if your not leaking anything....

Is this a new thing or has it been happening every time since you have been driving it?

Higgy
P.S. I love the smell of hot oil in the morning!!

[BB767]

Agreed, mixed with that rich exhaust aroma at first start!

Well, I am just starting to feel out the performance curve, I have only been on the road for two weeks now, so I guess it has "always done it" when I push the go pedal more about 1/4 of the way down, which has only been about four or five times so far.

I swear, no leaks! I will consider your suggestion but I am pretty sure the oil filler cap and PCV holes are different and they could not be easily swapped.

[Boydster]

oil cap is tight and properly vented, PCV valve is clean and vent tube is firm and in place,

Oil cap is the breather, right? And the hose from this goes to the air cleaner? Not an open breather?

And the PCV hose goes to throttle body / manifold vacuum?

Just double checking what you are saying there...

[Itchief]

Do you have power steering?

If so make sure the pump isn’t getting to hot I kept trying to find the hot oil smell on mine ended up replacing the pump and adding an oil cooler

Good luck

Rick

[mike223]

Open throttle blow by (high cylinder pressures) on a loaded V8 engine is pretty much always going to be more than you can fit through a pcv valve.

Until it starts ejecting oil it's nothing to worry about.


An alternate additional venting method would be to vent the breather to the air cleaner - this was often done in the 1970s OEM.

https://www.jegs.com/i/Moroso/710 (https://www.jegs.com/i/Moroso/710/68781/10002/-1?CAWELAID=1710622920&CAGPSPN=pla&CAAGID=44693592161&CATCI=aud-224375369591:pla-224831528231&CATARGETID=230006180039217893&cadevice=c&gclid=EAIaIQobChMIlfK-l-XZ3AIVxBuBCh2LxAhtEAQYBSABEgLAQ_D_BwE)



Lots of drag racers used to vent both valve covers to the headers (I think NHRA banned it due to header fires on blown engines / oil on dragway).

https://www.jegs.com/i/Allstar-Performance/049 (https://www.jegs.com/i/Allstar-Performance/049/ALL34145/10002/-1?CAWELAID=230006180000860922&CAGPSPN=pla&CAAGID=44693592161&CATCI=aud-67754331191:pla-190198847111&CATARGETID=230006180039218446&cadevice=c&jegspromo=nonbrand&gclid=EAIaIQobChMI4--ysOXZ3AIVhbrACh2YHgPsEAQYBCABEgLf2fD_BwE)

[BB767]

Oil cap is the breather, right? And the hose from this goes to the air cleaner? Not an open breather?

And the PCV hose goes to throttle body / manifold vacuum?

Just double checking what you are saying there...


Yes to all

[BB767]

Do you have power steering?

If so make sure the pump isn’t getting to hot I kept trying to find the hot oil smell on mine ended up replacing the pump and adding an oil cooler

Good luck

Rick

Actually, I have been keeping an eye on that as well. After driving, and the car is parked in the garage for the night, I have been checking temps (with my handy new IR gun thingy) and oddly enough the hottest thing (after the headers) in the engine compartment is the PS pump. But would that cause the "instant on, instant off" smell? Seems that would either be there most of the time, or not.

[BB767]

Open throttle blow by (high cylinder pressures) on a loaded V8 engine is pretty much always going to be more than you can fit through a pcv valve.

Until it starts ejecting oil it's nothing to worry about.


An alternate additional venting method would be to vent the breather to the air cleaner - this was often done in the 1970s OEM.

https://www.jegs.com/i/Moroso/710 (https://www.jegs.com/i/Moroso/710/68781/10002/-1?CAWELAID=1710622920&CAGPSPN=pla&CAAGID=44693592161&CATCI=aud-224375369591:pla-224831528231&CATARGETID=230006180039217893&cadevice=c&gclid=EAIaIQobChMIlfK-l-XZ3AIVxBuBCh2LxAhtEAQYBSABEgLAQ_D_BwE)



Lots of drag racers used to vent both valve covers to the headers (I think NHRA banned it due to header fires on blown engines / oil on dragway).

https://www.jegs.com/i/Allstar-Performance/049 (https://www.jegs.com/i/Allstar-Performance/049/ALL34145/10002/-1?CAWELAID=230006180000860922&CAGPSPN=pla&CAAGID=44693592161&CATCI=aud-67754331191:pla-190198847111&CATARGETID=230006180039218446&cadevice=c&jegspromo=nonbrand&gclid=EAIaIQobChMI4--ysOXZ3AIVhbrACh2YHgPsEAQYBCABEgLf2fD_BwE)


As Boydster said, the oil cap is vented to the air cleaner already and the PCV valve is vented to the intake at the base of the EFI unit. I understand what you are saying but wonder where the smell is coming from.

[Itchief]

You could be getting oil from the pump overflow blowing onto the headers once the pump gets hot and you rev the motor do you have any ps fluid leaking after you park

Just a thought

[BB767]

You could be getting oil from the pump overflow blowing onto the headers once the pump gets hot and you rev the motor do you have any ps fluid leaking after you park

Just a thought

No, as I said the engine compartment is completely dry. Although I have been checking the PS fluid level regularly I have not been checking right after each drive. I have not seen a "pump overflow", I'll look closer, your idea sounds plausible, and I'll try and keep a closer eye on the fluid level, although if it is just putting out a fine mist very occasionally it will be a while before I expect to notice any measurable drop.

Did your pump exhibit any other warning signs besides being smelly?

[Itchief]

It just had a hot smell during that period of time I lost my sense of smell due to blood pressure meds my wife kept telling me something smells hot when I would park the car

Hope you find the problem

Rick

[BB767]

It just had a hot smell during that period of time I lost my sense of smell due to blood pressure meds my wife kept telling me something smells hot when I would park the car

Hope you find the problem

Rick

Thanks Rick,

Just checked it. The PS fluid was slightly (1/8 in.) over the cold full level (I lowered it) and there was a slight film on the valve cover edge just behind the reservoir. You may have found the problem, I'll let you know in a few days.

[j.miller]

1. Amazon Prime...….Nose Plugs $2.99 available tomorrow......B. Vicks Vapor Rub on the upper lip......DRIVE IT LIKE YA STOLE IT !!!.....I get accused of taking the easy way out all the time.....I concur !!!...da Bat

[BB767]

1. Amazon Prime...….Nose Plugs $2.99 available tomorrow......B. Vicks Vapor Rub on the upper lip......DRIVE IT LIKE YA STOLE IT !!!.....I get accused of taking the easy way out all the time.....I concur !!!...da Bat

All the right answers, all the time! I knew I should have asked you first...................:cool:

[Gumball]

Probably a different issue, but just something to mention.

I was getting an intermittent oil smell when turning right recently and found that after 12k miles, the foam in the sealed breather (emission tube goes to bottom of air cleaner) on my left valve cover was saturated with oil and a small amount was seeping from the pressed seam on the breather housing and dripping a very small amount down on the header flange under hard right turns.

New breather and the smell is gone - going to have to remember to replace that more often.

[GoDadGo]

Have you checked to see if you have any oil leaks on the China Walls?

On a big inch SBC a weak or ineffective breather system will often cause those gaskets to get pushed out.
While you may not see a leak, or have much or even any seepage, sometimes those gaskets can get compromised.
I've got two breathers with NO PVC valve at the present time.
I'll likely plumb tube type breathers up to the air filter base at a later date.

China Walls: The front and rear portion of the engine block that protrudes up to meet the intake manfold.

[Avalanche325]

A couple things to check:

Re-torque your intake. If may take a few times to settle in.
Check your dipstick. See if it has pushed up out of the tube.

All engines have blow-by. New high performance engines can have a HUGE amount at high RPM. I blew the dipstick out of mine about an inch and thought I blew the engine when the oil hit the headers. They do settle down when they break in.

If it is power steering, the silly angle that Ford pumps are on can cause you to sling fluid on a hard right turn. It shouldn't happen on the street, but does on the track. There is an easy fix for that. You cut the filler tube about 2 in from the top and put a 10 inch piece of fuel filler hose on, then put that top piece with the cap back on. Hose clamp on the top and bottom and you are good.

[GoDadGo]

A couple things to check:
All engines have blow-by. New high performance engines can have a HUGE amount at high RPM.
They do settle down when they break in.
.

Excellent Point Made So Is The Engine Broken In Or Is It Still Getting There?

[j.miller]

All the right answers, all the time! I knew I should have asked you first...................:cool:

I KNOOOOOW ! RIGHT !!!:rolleyes:

[BB767]

Good points, I'll pay attention to all of them going forward. Engine now has a whopping 305 miles on it!

[GoDadGo]

Good points, I'll pay attention to all of them going forward. Engine now has a whopping 305 miles on it!

You are still very much in the early stages of the break in period.

Consider changing the oil by the 500 mile mark and keep on driving that sucker.

[BB767]

It just had a hot smell during that period of time I lost my sense of smell due to blood pressure meds my wife kept telling me something smells hot when I would park the car

Hope you find the problem

Rick

Well Rick, I think you are the winner! First drive after adjusting the fluid level in the PS pump, and, no more hot oil smell! This forum is GREAT! Now, if I can only figure out where that burning rubber smell is coming from after hard acceleration................:rolleyes:

[Just puttering]

When you start getting the burning rubber smell, turn the wheel to left and count to one, you should be able to see whats causing it! :)

[Itchief]

Sometimes even a blind squirrel will find a nut

[BB767]

when you start getting the burning rubber smell, turn the wheel to left and count to one, you should be able to see whats causing it! :)

lol.............

[DavidW]

I have the same odor and found that its coming from oil leaking from the DS valve cover onto the header. I'm going to change the valve cover gaskets and hopefully that will fix the problem. Going to get the Fel-Pro PermaDryPlus and hopefully that will do it.