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Water in the Oil
Posted: Sat Jan 10, 2026 5:30 pm
by John_Aldrich
NOT good.
Pulled the engine to put a rebuilt transmission on.
Put the car back together and when I checked the oil prior to starting the car it had oil in it (I installed a dipstick years ago).
Changed the oil and pulled the head thinking I had a blown head gasket. Replaced the head gasket (didn't really look bad) and reassembled.
Started the car and it started fine although I got blue smoke out of the exhaust initially. Not sure why. The longer the car ran the worse it would run (maybe 3 minutes long)
Head bolts are tight and has a new gasket. All I can think of is a cracked block.
Anyone have another idea?
Re: Water in the Oil
Posted: Sat Jan 10, 2026 5:34 pm
by JTT3
Just spitballing here.
Any chance tightening the head bolts you went into the jacket?
Have you ever decked the block & head?
Any freeze plug leaking water into the valve gallery?
Crack running from valve sleeve to cylinder or a crack in the cylinder wall?
Crack in the head on gasket side
Re: Water in the Oil
Posted: Sat Jan 10, 2026 5:47 pm
by TXGOAT2
100% fresh gasoline? Did the engine run well before the work? How much water in the oil? Did it run with water in the oil? Plain water or water and antifreeze? Could be a a gasket issue, a crack, or condensation if the amount was small. Is there any chance that washing the powerplant prior to the work could have gotten water in it? T engines aren't water tight.
I'd recheck for water at the drain plug, and pull the plugs and look for any evidence of moisture. If none is evident, I'd run the engine to operating temperature and look for bubbles in the radiator tank and any evidence of excessive steam at the exhaust or at the oil fill cap.
Re: Water in the Oil
Posted: Sat Jan 10, 2026 6:34 pm
by Mike Silbert
Perform a leak down test and check for air out the radiator to test the head gasket seal.
Or look for radiator bubbles when running.
This will give the answer or rule it out.
Now it might only leak when warmed up.
A leak down test will tell other things besides head gasket condition also.
It is difficult and risky to pressurize the radiator and look inside for drips.
Look for green drips up inside the bottom of the engine with the inspection cover off.
Mike
Re: Water in the Oil
Posted: Sun Jan 11, 2026 7:39 am
by Joe Bell
Is it a 26-7 block? real problem cracks in the valve chamber between 2+3 cylinder going from main bolt to soft plug, i have pitched many blocks from this problem. take valve cover off and look up or use a mirror to see if rust is there or a crack.
Re: Water in the Oil
Posted: Sun Jan 11, 2026 10:11 am
by TXGOAT2
How much water was in the oil? Was a significant amount of water missing from the radiator?
Re: Water in the Oil
Posted: Sun Jan 11, 2026 11:31 am
by John_Aldrich
JTT3 wrote: ↑Sat Jan 10, 2026 5:34 pm
Just spitballing here.
Any chance tightening the head bolts you went into the jacket?
Have you ever decked the block & head?
Any freeze plug leaking water into the valve gallery?
Crack running from valve sleeve to cylinder or a crack in the cylinder wall?
Crack in the head on gasket side
Appreciate all the feed back.
How much water in the oil? The short time I ran it the water turned the new oil milky so it's getting there fast.
I'll start checking for cracks and yes, it's a 1927 block on a Canadian built car.
Z head never decked. Don't know if the block has been decked.
Engine ran well prior to repair. I did remove the distributor and went back to coils.
Re: Water in the Oil
Posted: Sun Jan 11, 2026 11:51 am
by TXGOAT2
Fresh oil will turn milky very quickly after start-up with even a small amount of water present. In cold weather, oil can turn milky after start up with NO free water present, due to water vapor normally released during the combustion process.
You may have a problem, or you may not. In colder weather, it's common for white moisture slime to form inside valve covers and oil filler caps on engines that have not reached full operating temperature and run for a period of time to drive off the moisture. In cold weather, some engines will accumulate condensate inside valve covers and oil filler pipes and road draft pipes even after being driven for miles.
Every gallon of gasoline burned releases about 3 gallons of water. Most of it goes out the exhaust as steam or condensate, but some of it gets past the rings and then it condenses in the crankcase and any other place inside the engine that is not hot enough to prevent it. This effect is more pronounced in damp weather. In engines that are not driven for miles in cooler weather once started, a considerable amount of water can accumulate in the crank case. Model T engines don't have the best crank case ventilation, and they can, under short trip driving in cooler weather, accumulate a substantial amount of moisture and even free water in the crankcase. On place that is very vulnerable to moisture accumulation is an accessory dipstick, which will stay much cooler than the rest of the engine, and thus condense moisture on the dipstick and inside the dipstick tube.
Re: Water in the Oil
Posted: Sun Jan 11, 2026 1:21 pm
by John_Aldrich
TXGOAT2 wrote: ↑Sun Jan 11, 2026 11:51 am
Fresh oil will turn milky very quickly after start-up with even a small amount of water present. In cold weather, oil can turn milky after start up with NO free water present, due to water vapor normally released during the combustion process.
You may have a problem, or you may not. In colder weather, it's common for white moisture slime to form inside valve covers and oil filler caps on engines that have not reached full operating temperature and run for a period of time to drive off the moisture. In cold weather, some engines will accumulate condensate inside valve covers and oil filler pipes and road draft pipes even after being driven for miles.
Every gallon of gasoline burned releases about 3 gallons of water. Most of it goes out the exhaust as steam or condensate, but some of it gets past the rings and then it condenses in the crankcase and any other place inside the engine that is not hot enough to prevent it. This effect is more pronounced in damp weather. In engines that are not driven for miles in cooler weather once started, a considerable amount of water can accumulate in the crank case. Model T engines don't have the best crank case ventilation, and they can, under short trip driving in cooler weather, accumulate a substantial amount of moisture and even free water in the crankcase. On place that is very vulnerable to moisture accumulation is an accessory dipstick, which will stay much cooler than the rest of the engine, and thus condense moisture on the dipstick and inside the dipstick tube.
Very interesting. Once I get a heli coil in this newly stripped head bolt I'll reassemble and try to see if I can "burn" the water out!
I live in a very humid and "wet" area of Washington state with a year round creek in my backyard.
Re: Water in the Oil
Posted: Sun Jan 11, 2026 3:11 pm
by TXGOAT2
I'd raise the front of the car about 8 to 10 inches, then drain the oil into a clean container and look for any free water. If there's very little or none, and NO evidence of antifreeze, I'd put the oil back in the engine, reserving and discarding any free water. But if the oil is very milky or visibly water cut, I'd replace it. If it's slightly milky, it isn't likely to do any harm. It's important to drive the car for at least ten miles on the open road, and more is better. 20 t0 40 miles at 30 MPH or so would be nice. It takes a while for the engine, transmission and the oil to fully warm up, and once warm (hot, actually) the engine needs to run for a while to allow time for the moisture to be driven out. Be watchful for any sign of water leaking from the radiator. It's best not to start a car unless you are going to drive it ten miles or more, and more is better. That's especially true in cool humid weather.
Re: Water in the Oil
Posted: Sun Jan 11, 2026 3:19 pm
by TXGOAT2
Z head? Aluminum heads require a specific torquing procedure and several re-torques. Stock head bolts may not be the right length for a Z head, and bolt heads must have steel washers under them when used with an aluminum head. The aluminum head is a different animal than the stock cast iron head.