moisture

[jamie18]

I'am pretty sure I know what the answer is going to be but I just want to make sure before I replace the head gaskets on my truck. I'am getting some
moisture in the valve covers and on the engine oil dipstick. Any input would be appriciated. Thank you!!!

 

[Natedog]

I'am pretty sure I know what the answer is going to be but I just want to make sure before I replace the head gaskets on my truck. I'am getting some
moisture in the valve covers and on the engine oil dipstick. Any input would be appriciated. Thank you!!!

Head gasket, cracked head, cracked block....prolly the head and/or head gasket. Has it gotten hot or low on water?

 

[Jspafford]

Wait, how do you know you are getting in inside the valve covers? From the oil cap?

 

[AllanD]

Blown headgaskets on a 2.9? Unicorn

cracked heads? like potheads at a grateful dead concert.

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[Broncodude]

unless your just wanting to take it apart, I'd try some bars stop leak first..have you done all the test you need to first?

 

[jamie18]

I loose about a quart to a half gallon once a month. I have checked for leaks and there are no obivious leaks present. As for how do I know I took the oil filler cap off and notice white milky subtance inside and ran my finger around the inside the best I could and it was pretty thick. I really appreciate the replies I have received ,I hope its just the Headgaskets and not a cracked head. Again thanks for the input !!!

 

[Hahnsb2]

Have you drained your oil? If its milkshake, you've got a bad head or gasket. If its not, what you're seeing on the the oil cap is condensation, which is fairly common.

 

[Sunk]

As AllanD said, its probably not a head gasket, but a cracked head. This happened to me, so I swapped in another 2.9 with 60,000 less miles. I'd drain the oil to rule out condensation. From what it sounds like, its a pretty slow leak. You may get lucky and it could just be condensation.

 

[jamie18]

My oil is not milky looking so it sounds like I've got some condensation. In a fact I've noticed when I do add coolant it seems it drops to about the same level and pretty much stays their. I don't know about all the 2.9s but my brother has an 89 4x4 and he says his coolant drops a little and stays at that level. I really appreciate all the advice , Thank You !!!

 

[Tynaje]

I just logged on to ask about the same issue. This summer I removed my thermostat when the truck got hot, it didn't get steamy hot though. I got lazy and neglected to install a new thermostat. It recently got cold here in RI and it has become time to put one back in for some heat.
The truck actually lost temperature. It runs really smooth, not a sign of trouble. There was not a sign of heat, so I thought perhaps I might be low on coolant, could be why the heat wasn't working.
I was a qt low on oil, added it and noticed moisture on the inside of the cap. When I removed the radiator cap, brown foam! It runs so good, I can't believe it has a blown gasket. Reading these posts, I just can't believe it may have a cracked head, but I had no idea I had gasket issues.
What causes the temperature to drop when a gasket is blown? Or what other issue has caused the temperature to stay low. The truck never developed heat last year as well.

 

[Hahnsb2]

My oil is not milky looking so it sounds like I've got some condensation. In a fact I've noticed when I do add coolant it seems it drops to about the same level and pretty much stays their. I don't know about all the 2.9s but my brother has an 89 4x4 and he says his coolant drops a little and stays at that level. I really appreciate all the advice , Thank You !!!

Mine does it too.

 

[MAKG]

The temperature doesn't drop. Coolant stops flowing because it boils, and the temperature gauge is FOS because it isn't immersed in coolant. ANY unusual temperature reading at the gauge is cause for going over the cooling system.

And FYI, absence of baby barf in the crankcase does not rule out head cracks. It only rules out really big ones. Condensation is a likely possibility ONLY if the truck is driven only very short distances, to prevent full warm up of the oil. Get it above boiling there (which is very easy), and it will slowly purge out the PCV system.

Mystery coolant disappearance does suggest a head crack, but double check the water pump first. And just to be sure, leaks are NOT identified by puddles. Only really big leaks make those. They are identified by crusty deposits around the hoses, core plugs, radiator core, heater hoses, and so on, and ESPECIALLY corrosion tracks on the bottom of the water pump. Everyone seems to miss that last one.

If you are BURNING coolant -- which makes persistent sweet-smelling white smoke even when the engine is completely warm -- you likely have a head crack, but can easily confirm it by pressurizing each cylinder to 100 PSI at TDC/compression with the radiator cap removed. If it's blown, you'll see the air coming through the cooling system. There are no in-situ tests that can distinguish a head crack from a blown head gasket (excepting a borescope with a crack big enough to actually be seen), but either requires removing the head in question, and it can easily be Magnafluxed then. The pressurization distinguishes a blown lower intake gasket.

Note that head cracks do not have to enter the cylinder, and mild ones often don't.

The thing that nails people is that the vehicle can run nicely with a mild head crack, until it starts to eat the crank and rod bearings, or until it overheats enough to "flatten" the pistons. At which time a $500 repair has turned into a $2000 repair. By the time this happens, the engine will make all kinds of periodic knocking sounds, will start smoking (burning oil through scored cylinders), and may seize or break.

 

[Tynaje]

The temperature doesn't drop. Coolant stops flowing because it boils, and the temperature gauge is FOS because it isn't immersed in coolant. ANY unusual temperature reading at the gauge is cause for going over the cooling system.

And FYI, absence of baby barf in the crankcase does not rule out head cracks. It only rules out really big ones. Condensation is a likely possibility ONLY if the truck is driven only very short distances, to prevent full warm up of the oil. Get it above boiling there (which is very easy), and it will slowly purge out the PCV system.

Mystery coolant disappearance does suggest a head crack, but double check the water pump first. And just to be sure, leaks are NOT identified by puddles. Only really big leaks make those. They are identified by crusty deposits around the hoses, core plugs, radiator core, heater hoses, and so on, and ESPECIALLY corrosion tracks on the bottom of the water pump. Everyone seems to miss that last one.

If you are BURNING coolant -- which makes persistent sweet-smelling white smoke even when the engine is completely warm -- you likely have a head crack, but can easily confirm it by pressurizing each cylinder to 100 PSI at TDC/compression with the radiator cap removed. If it's blown, you'll see the air coming through the cooling system. There are no in-situ tests that can distinguish a head crack from a blown head gasket (excepting a borescope with a crack big enough to actually be seen), but either requires removing the head in question, and it can easily be Magnafluxed then. The pressurization distinguishes a blown lower intake gasket.

Note that head cracks do not have to enter the cylinder, and mild ones often don't.

The thing that nails people is that the vehicle can run nicely with a mild head crack, until it starts to eat the crank and rod bearings, or until it overheats enough to "flatten" the pistons. At which time a $500 repair has turned into a $2000 repair. By the time this happens, the engine will make all kinds of periodic knocking sounds, will start smoking (burning oil through scored cylinders), and may seize or break.

I have heard the periodic knocking, not bad, but I have heard it recently. I bought the truck little over a year ago. It has run really well, passed emissions with flying colors. It has always lost a qt of oil every couple of months with no signs of a leak, intil now. This truck must have gotten hot before I bought it I guess. I put nearly 40,000 miles on it in a year, all local and one 600 mile trip. It hasn't been the same since 6 hours at 70 mph.
It sounds as if this thing is toast, even though it is still running great. What is the next step, assuming I have parked it?

 

[Hahnsb2]

I have heard the periodic knocking, not bad, but I have heard it recently. I bought the truck little over a year ago. It has run really well, passed emissions with flying colors. It has always lost a qt of oil every couple of months with no signs of a leak, intil now. This truck must have gotten hot before I bought it I guess. I put nearly 40,000 miles on it in a year, all local and one 600 mile trip. It hasn't been the same since 6 hours at 70 mph.
It sounds as if this thing is toast, even though it is still running great. What is the next step, assuming I have parked it?

You're probably hearing a lifter tick, most 2.9s do it, and in most cases the engine is fine and will run like that for a long time. Mine only does it on start up, my dads does it whenever it feels like it. All our parts rigs with 2.9s tick.