my encounter with engine gnome
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Elder User
Joined: Dec 2002
Posts: 550
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From: Effingham,IL USA
my encounter with engine gnome
im pretty sure i had a visit from an engine gnome. i rebuilt my 83 f100's 302 last year and its been runnin greatever since. then on prolly the third oil change after the rebuild i was at work and pulled the truk in and changed the oil and about a quart of pure antifreeze poured out b4 the oil. i thought "dam there goes the intake gasket" and finished the oil change. have been checking for coolant in the oil ever since (loosening the drain plug and watching what comes out) and theres absolutly no coolant in it. it was just a one time thing. im forced to believe it was a visit from an engine gnome and he poured antifreeze into my oil, maybe cause i havent been working on the old girl as much as i should lol.
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Joined: Apr 2005
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A lack of pressure in the system can cause this. When you had the anitfreeze in the oil, the cooling system was sealed and under pressure. The pressure forced the water into the oil, either through a bad gasket, or through a pore in the block. Did you bore the block? Sometimes causes pores to release coolant into the oil. Another possibility is a crack in a head that only shows up under pressure. I would definately test the radiator and cap for holding pressure.
Do you have any pressure in the cooling system when the engine is hot? It is possible that the cooling system is venting somewhere (leaking) and not building pressure. This is bad. The water will boil in the block. If the water is boiling, then air bubbles are against the metal in the inside of the block, and the water will not transfer heat. The metal, although a temperature guage will not show overheat, will be too hot. The pressure on the water from the cap prevents the water from boiling, therefore providing cooling. To see if there is pressure, when the engine is hot, see if the upper radiator hose is hard ot squeeze. You could also get a radiator tester. It pumps up pressure in the system and allows you to test if the system leaks.
If you restore pressure to the system, be aware that the leak into the oil may start again.
Do you have any pressure in the cooling system when the engine is hot? It is possible that the cooling system is venting somewhere (leaking) and not building pressure. This is bad. The water will boil in the block. If the water is boiling, then air bubbles are against the metal in the inside of the block, and the water will not transfer heat. The metal, although a temperature guage will not show overheat, will be too hot. The pressure on the water from the cap prevents the water from boiling, therefore providing cooling. To see if there is pressure, when the engine is hot, see if the upper radiator hose is hard ot squeeze. You could also get a radiator tester. It pumps up pressure in the system and allows you to test if the system leaks.
If you restore pressure to the system, be aware that the leak into the oil may start again.
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Elder User
Joined: Dec 2002
Posts: 550
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From: Effingham,IL USA
well the cooling system always has held good pressure since the rebuild. the radiator was leaking a little and i had it repaired around the time of the incident. block is bored 60. engine never runs hot and always has very high oil pressure- 60 psi. heads and block arent cracked- they all went to machine shop and came back together. engine was never overheated since rebuild. oil was perfect after all previous oil changes. no smoke out exhaust. no leaks. drivin the truck more than 10,ooo miles since rebuild with no problems except the one time the coolant was in the oil. the oil and coolant were completely seperate when they came out. im assuming the water wasnt in there for long or it would have mixed with the oil. the engine was runnin minutes before the drain plug was loosened. im still thinkin it was the gnome.
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Joined: Oct 2004
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From: Winnipeg, Manitoba
I'd suspect a gaskt was seating itself.
One thing on rebuilds...head gaskets are especially prone to this issue. You need to follow exact tourque procedures. Normally you would tighten all bolts to a given spec, and then retourque to a higher spec, and then do so again, and then check those tourque specs after initial run-in and cool down.
This allows for gasket settling and seating. I'd retourque ever head bolt with the proper tourque config according to your manual on the head bolts and intake bolts. It never hurts to do this for all bolts after an initial run-in.
One thing to remember, even oil pan and valve cover bolts have a tourque value. Some are in inch/lbs, some are in ft/lbs. Best investment you can make is a good quality tourque wrench, never mind following procedure.
One thing on rebuilds...head gaskets are especially prone to this issue. You need to follow exact tourque procedures. Normally you would tighten all bolts to a given spec, and then retourque to a higher spec, and then do so again, and then check those tourque specs after initial run-in and cool down.
This allows for gasket settling and seating. I'd retourque ever head bolt with the proper tourque config according to your manual on the head bolts and intake bolts. It never hurts to do this for all bolts after an initial run-in.
One thing to remember, even oil pan and valve cover bolts have a tourque value. Some are in inch/lbs, some are in ft/lbs. Best investment you can make is a good quality tourque wrench, never mind following procedure.
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Elder User
Joined: Dec 2002
Posts: 550
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From: Effingham,IL USA
ya i followed the torque procedures to the letter with a torque wrench and used all fel pro gaskets. old fords dont need to retorque the head bolts, but my 91 pontiac i just did the head on did. u had to warm it up then retorque the bolts in sequence 1 last time. i really dont think its a blown head gasket or intake gasket cause the problem only happened once. blown head gaskets dont leak that much just once and not have any other problems. its that dam gmone!
