Creamy oil under a fill cap

[Joesdog]

Just dropped in a rebuilt 4.7 in my 2004 Ram and have noticed a small drop in radiator fluid as well as in the oil. I changed the oil at less than 1000 miles and no water is in the oil. I thought the timing chain cover gasket might be leaking. What are your thoughts? Before you ask, the oil fill was cleaned at the time of the rebuild, as well as all the other covers, pieces and parts. I know that old school engines used to use the intake to convey water from one side of the engine to the other. I don’t think the new plastic intakes do that, right? Thank you in advance for your thoughts and suggestions.

 

[Freakydude]

could be because its a rebuild! Any leaks anywhere? Any oil other than a drop in the rad? Engine smoke? Bad smell when its warm? I would double check everything and it may cost a couple bucks but an extra oil change will tell if it is coolant getting mixed. let the oil sit for a few minutes to allow things to separate if needed.
You could drain and flush the rad as well, that is fairly cheap and a well maintained vehicle isn't going to be hurt from it.

 

[HemiLonestar]

The oil cap is the high point in the system so that's where any moisture/condensation buildup ends up on it's way out. As long as your oil doesn't look like that you're good. Tends to happen less (this is my personal experience, so S-T-F-U oil nazis) with synthetic oil and proper warm ups. Start & go's and lotsa short trips aren't good for that engine. Besides emissions it's part of the reason modern vehicles run at higher temps.

 

[Travelin Ram]

A picture to illustrate the severity would be helpful. Modest amounts are not unusual particularly if operating in cool weather and short trips.

I would check the PCV system to verify it’s scavenging properly.

A one-time drop in coolant can be just replacing trapped air that burped from the cooling system. I’ve seen that on brand new vehicles. If it takes repeated addition, no bueno.

 

[EdGs]

+1 about condensation from short-tripping and burping of air in the cooling system.

Once the truck has sat for a day or so, crack the oil drain plug loose, but DO NOT remove it.

Loosen it just til it starts to drip and watch the drip. Coolant in the oil will make itself known in short order.

 

[jws123]

common on 4.7s this is normal to have gunk on filler cap

 

[Ole Buck]

did it look like this?

 

[HemiLonestar]

did it look like this?


View attachment 507443

I saw that pic yesterday with the caption that a lady poured a gallon and half of washer fluid in.

 

[GTyankee]

If you think the Oil Cap is dirty looking
Take a glance at the hose that goes from the EGR to the engine as a smog device, on the other hand, don't look at that hose.
You will be shopping for a Catch Can

 

[Lyle Longboat]

did it look like this?


View attachment 507443

This hurts just looking at it.

 

[Tadpole]

Clean the cap completely. Then take it for a 30 minute freeway trip. The trip will get the engine up to normal operating temp and will evaporate any remaining moisture. If you have a leak, there will be more foamy oil. Good luck!

 

[Dusty]

Just dropped in a rebuilt 4.7 in my 2004 Ram and have noticed a small drop in radiator fluid as well as in the oil. I changed the oil at less than 1000 miles and no water is in the oil. I thought the timing chain cover gasket might be leaking. What are your thoughts? Before you ask, the oil fill was cleaned at the time of the rebuild, as well as all the other covers, pieces and parts. I know that old school engines used to use the intake to convey water from one side of the engine to the other. I don’t think the new plastic intakes do that, right? Thank you in advance for your thoughts and suggestions.

Early 4.7s had the PCV valve mounted in the plastic oil fill tube near the oil cap. This had a tendency to pull hot, moist gases from the engine to a high point in the system that was relatively much cooler, thereby causing condensation to accumulate under the oil cap. A combination of water and oil produces that "creamy" substance.

Unless excessive, it's probably normal, especially when there's a lot of moisture in the air.

In 2004 they moved the PCV valve to the rear of the engine.

Regards,
Dusty
2019 Ram 1500 Billet Silver Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33-gallon fuel tank, factory dual exhaust, 18” wheels. Build date: 3 June 2018. Now at 80904 miles