source for milky oil?

[Krafty]

Ive got my 93 4.9 and for quite a while ive noticed under my oil cap there's been a milky residue, but the part that bothers me is the milky oil residue that gets sucked into my air box and drips out the bottom and makes the old truck look like some p.o.s.

I never get water in my oil when i do my changes, and my coolant level stays close to the same for months at a time.

so obviously I have a leak somewhere its just not excessive. its enough to steam in the valve cover but not enough to drip into the oil pan

my question is im debating between a head gasket, a complete rebuild minus the new rotating assembly, or **** it up and hope it doesn't get worse ( been like that for over a year)

the old gal has 230 000 k's or about 140 000 miles.

thanks in advance for the input,

 

[Fiero/Broncoman]

We had a old I6 amc that had the same issue. But it was cause we never drove it more than 10 miles at a time. So it never got hot enough to burn all the water from condensation pit of the oil. Once I got it from my parents i drove it 50 to 120 miles or more at a time. And i never had that issue with it.

 

[Krafty]

the milky fluid never goes away, not even with a 4 hour drive in the summer time. not the same problem.

 

[miesk5]

yo KRAFTY,

That does have lots of mileage. Ford says to fix it as advised below; a rebuild is in order before it gets worse and you end up w/ a yard engine or a reman unit (Consider a Ford Motorcraft long block because of warranty and quality)

For peace-of-mind;

if your 4.9 has an extternal oil cooler (as used in some V8's), check it out. If leak is found at oil cooler, the cooler must be removed and pressure tested for internal leaks. Repair or replace as necessary

then the usual tests

Get a Coolant Prssure tester Loan from a parts store

& do a Compression Check

this is by Ford...iggie the diesel info stuff; and as usual, I added more than asked, but worth the checks

NOTE: It is not sufficient to inspect only the coolant in the radiator coolant recovery reservoir (8A080). The coolant in the radiator coolant recovery reservoir may not be representative of the coolant in the rest of the system. For reservoir coolant to be representative of system coolant, engine must have been operated long enough and gotten hot enough for an extensive exchange of coolant between the radiator and the radiator coolant recovery reservoir since the last time coolant was added to the radiator coolant recovery reservoir.

Allow engine to cool and remove radiator cap.

Inspect coolant in both radiator and radiator coolant recovery reservoir. Coolant should be a green or blue color (depending on brand of antifreeze used).

Clear coolant or coolant only a very light green or blue indicates that there is only water or a very weak antifreeze mixture in the system. Advise the owner of the need for the correct 50/50 coolant mixture.

A very muddy brown color indicates an unauthorized brand of stop-leak has been used. This may eventually plug the system, causing overheating. Advise the owner that the best course would be to drain the system and repair the original concern, flush the system, and refill with correct 50/50 coolant mixture and, if necessary, Cooling System Stop Leak Pellet D9AZ-19558-A or Cooling System Stop Leak Powder E6AZ-19558-A or equivalent meeting specification ESE-M99B170-A.

Make clear to the customer that any stop-leak material is not a satisfactory repair for a serious cooling system concern such as a leaking water pump (8501), gasket, or radiator.

A reddish brown color indicates rust in the cooling system. Advise the customer that the best course would be to flush the cooling system and refill with the correct 50/50 coolant mixture. Ford Premium Cooling System Fluid, E2FZ-19549-AA or equivalent meeting Ford specification (ESE-M97B44-A and ESE-M97B43-A) contains corrosion inhibitors. In addition, add 1.4 liters (1.5 qts.) of Heavy-Duty Cooling System Additive FW-15 or equivalent meeting Ford specification ESN-M99B169-A.

An iridescent sheen on the top of the coolant indicates a small amount of oil entering the coolant. This is common in high-mileage vehicles.

CAUTION: If there is coolant in the engine oil, the cause must be corrected and the oil changed or engine damage will occur.Check the engine oil on the oil level dipstick (6750) to see if any coolant is entering the engine oil as indicated by drops of coolant visible in the oil or a milky appearance to the oil. If the oil checks out OK, inform the customer that, while not an immediate problem, the situation should be closely monitored during routine maintenance.

CAUTION: Severe oil leakage to the engine coolant, as indicated by a milky appearance to the coolant, must be corrected or severe engine damage will occur.If the coolant is a milky brown color (like coffee with heavy cream) engine oil is entering the coolant. On 7.3L diesel and 7.5L gasoline engines the most probable cause is a leak in the engine oil cooler. Remove and inspect to find the problem.

If the oil cooler checks out OK, the head gasket (6051) may be leaking around the oil passageway to the cylinder head (6049). It will be necessary to remove the cylinder head, inspect for the problem, and replace the head gasket. If the head gasket checks out OK, then a crack between an engine oil gallery and the cooling passageways could be the cause. Inspect the cylinder block (6010) and cylinder head. Refer to Section 03-00.

A reddish milky appearance to the coolant indicates that transmission oil is leaking into the coolant indicating a leaking transmission fluid cooler (7A095).

CAUTION: If coolant is found to be entering the transmission fluid, the cause must be corrected or transmission damage will occur.

Check transmission fluid to make sure coolant has not mixed into transmission fluid as indicated by a milky appearance. If it has, it will be necessary to flush transmission (7003) and replace filter outlined in the appropriate section. Refer to Group 07. Replace radiator assembly, flush cooling system, refill transmission, and refill cooling system with correct 50/50 coolant and antifreeze mixture.

If chunks of rust are visible on top of the tubes in downflow radiators or in the inlet tank in crossflow radiators, flush the cooling system.

If there is puffy white corrosion around the tubes where they are attached to the core headers, flush the system. If there is corrosion on aluminum radiator parts, there is going to be corrosion on aluminum engine parts that come in contact with coolant.

Advise the owner of the importance of using the proper 50/50 mixture of water and Ford E2FZ-19549-AA Premium Cooling System Fluid or equivalent meeting specification ESE-M97B44-A that contains corrosion inhibitors. In addition, add 1.4 liters (1.5 quarts) of Heavy-Duty Cooling System Additive FW-15 or equivalent meeting Ford specification ESN-M99B169-A.

 

[BroncoJoe19]

Krafty,

I can't speak from experience, but I have heard that the newer stop leak products are better than those of the past. A couple of mechanics on another site I frequent reported that they have sucessfully used (I think it was Bar's head gasket repair). You might want to search into that concept as a possibility. Then when the weather warms pulling the head and replacing the gasket may be in your future.

Just a thought

 

[Krafty]

one of my thoughts on doing the head gasket is since im going that far into the engine should I just pull it and do rings and mains anyways so when it goes back in I know its all brand new.

but unlike the v8s i cant seem to find much selection on full rebuild kits to compare prices.

what im going to do when I get it to my dads shop is im gonna do a compression test on the rad, do compression test on my cylinders and go from there.

 

[BroncoJoe19]

Pulling an engine is too big a job for me, so I'd lean towards just doing the gasket. Especially if the engine isn't burning oil, or isn't making any noises.

 

[Krafty]

So i did an oil change today cause it was due, while I was under the truck I noticed there was alot of oil accumulated at the front of the oil pan below the crank pulley, I put a socket on all the bolts in that area and a couple of them were barely snug, ill have to keep an eye on the oil situation to see if there is a change or not, but I had no milky color in my oil from my pan. its just a heavy build up on my oil cap and in my breather still.

 

[nelbur]

I think you are just seeing condensation from the blow by on a well worn engine. It will likely go away when it gets warm again. When the blow by gets high enough the PCV system can not evacuate the blow by fast enough to pull dry air into the crankcase. So the moisture from combustion just condenses on the coolest part of the crankcase, which is the valve covers. Your oil cap is a valve cover inspection port. Put in a new PCV valve to maximize crankcase ventilation. High blow by engines tend to oil up the PCV system filter in the air cleaner, so replace this as well so you get maximum ventilation when you are at idle, where blow by is low and vacuum is high. This might reduce the condensation in your valve covers/oil cap.

 

[Krafty]

that would explain why I would have milky oil in the valve covers and not in the pan, I was sure that if it was a gasket then my oil and coolant would show signs of contamination which they are not, I was considering doing rings anyways but now it sounds like the only way to go, thanks nelbur.

 

[nelbur]

I guess what I am saying is that what you are seeing is likely normal for a worn engine in a cold temperature area. I would not recommend doing the rings without doing the bearings, etc., etc. If it is running fine, just keep driving it. Worn engines happen and there are ways to live with the wear, like going to thicker oil to get better oil pressure and a bit more compression, and dealing with the oil that is forced into the PCV filter by adding a puke bottle of some kind to keep the air filter from getting oiled down. If you get tired of living with it, I would recommend you install a re-manufactured long block where everything has been gone over.

 

[Bully Bob]

I'm thinking best case scenario.

How 'bout a press. test on the radiator., & a compression test on the cylinders.

I'm guessing it's an intake man. water leak. :-"

 

[Krafty]

Im not afraid to dig in and get dirty, there's always the work truck if I hit a snag, my problem at this point is the money, the re-manned block sounds awesome but at an average price of 1100 to 1600 its just not an option, considering I only paid 1300 for the truck 2 years ago,

my other issue is when I do all this work there are a couple of other things I should address at the same time like my high pressure leak in my rad, my rotted out a/c condenser and my oil pan has some nasty rust on it, and im sure if I look hard enough I can find a couple more things.

at this point its not a matter of "if", its a matter of "when I can afford" to do all of this.

also I think I already know the answer to this but ill ask anyways, would moderate blow by cause an EGR code?

oh and on the intake leak, how would an intake that goes directly into the head without a lifter valley cause this without my valve seals being toast,

I know what bad valve seals do and this truck does not have ANY of those symptoms, nor do I have any white smoke but thanks for thinking outside the box.

 

[Bully Bob]

"oh and on the intake leak, how would an intake that goes directly into the head without a lifter valley cause this...?"

If not mistaken., water runs thru the intake passages & into the heads.

The intake & gasket seal the "valley"

A failed/faulty intake gasket, allowing water to drip into the valley, would muck things up... :angry:

 

[Krafty]

I don't mean to be rude but its a 4.9 and it doesn't have a valley or more than one head. if it was a 5.0 or 5.8 you would be right.

 

[Elmo]

if you didnt see any milky come out when you changed the oil i would say you can rest your mind and call it condensation collecting in the cap. I had a 79 F100 with the 300 I6 in it and it did the same thing never got better never got worse i scraped the truck when #1 cilinder lost compression there fore making it too week to drive very well. still had clean oil and was not loosing any coolant

 

[Krafty]

At this point your right, im not too worried about my oil anymore, but on the topic of blow by and bad rings, I have noticed some changes in the way it runs over the last couple years, made more noticeable by the 31's .

I have 3 options, run it into the ground see how long it lasts and eventually buy another truck.

fix it up right and put another 140 000 miles on it

or fix it up right and build it up to a level that I could sell it and make some good coin.

either way I have a feeling this will be the last of the 80 to 96 styles for me until I have room for more than one project.

I like option 2, but if I do a bunch of work to the motor and a little while down the road something in my trans starts going ill never hear the end of it.

but we'll see

 

[nelbur]

Option three is not workable. If you spend big money on an old bronco, you will be lucky to get half of it back when you sell. This is true of cars, trucks, and boats. The common sellers lament is, "but I have way more than that in it." Do what makes sense to you for your use. Forget about resale. It will sell for less than you think is reasonable anyway. The way to make money on fixing up and selling an old vehicle is to get one that is modestly used that can be fixed for small money. That, you can fix up and sell for a profit.