Coolant in the oil?

usered

Senior Member
I have a 1939 v8 flathead that I had built several years ago. recently finally got to a point of starting it. Started fine went through a break in procedure. Several hours later I noticed coolant around some of the head bolts and spark plugs.
I restarted the motor warmed it up and re-torqued the head bolts. Same results coolant around the head bolts and plugs. It is now blowing smoke out the exhaust and when I checked the oil it appeared to be about 1/2 quart high. Oil was black not a milky color. Should mention I have Offenhauser heads on the motor.

Is it possible that coolant is leaking around the head bolts into the cylinders?

Any thoughts on what to check?
 
Studs or bolts? Check and see which ones are leaking, they may not have been sealed. If it is blowing water vapor out the exhaust that is another issue.
 
What radiator cap psi ? What head gaskets and any sealant under head bolt / nut flat washers ?
 
I always use sealant on the stud threads and for my initial run up start it with NO coolant in it and get it up to a temp where it feels too hot for my hand on the head and shut it off. Let sit overnight, Retorque, fire it up again, run it up to temp, shut off, let sit overnight, retorque.
After the 3rd cycle when cold after retorquing, I put the coolant in and then run it.
Aluminum heads should be torqued when cold, cast iron when hot.
 
Why hot for cast iron? I always let them cool also. Seems like they would grow when hot and shrink when cool thus affecting torque reading.
 
Thanks for the responses.

Using studs, smoke is much more then moisture in the exhaust. When you say sealant on the studs, all studs? What kind of sealant?

Its kind of hard to determine specific studs, seems to be the top ones leaking down to the low spots plugs etc.

Will have to check on radiator cap PSI, what should it be?
 
Radiator cap 0 or up to 7 psi . Steel flat washers used with aluminum heads under nuts . Permatex works for me . I also spray the head gaskets with silver paint , couple of Coates , both sides . Always retorque 3 times after a warm / cold cycle . I also start without water till warm to the touch and shut off , retorque, repeat . Then add water . Of course when cold .
 
Will try putting sealant on all the studs, use a flat washer and re-torque heads as suggested hot/cold three times without coolant.

Thanks
 
If there is smoke from coolant coming out the exhaust now i´m not sure just tightening up the heads is the way to go now.
If you can get to the exhaust manifolds easily take them off and start up then you now what or if multiple ports you have smoke coming out of.
Then take heads of and start from there.
First find the problem...before starting to aply random bandaids...
 
In a world were the head gasket seals tight. bolt leakage is annoying, but does not put coolant in the cylinder or crank case. Typically. Cycling the heads is good, but then Open it up. Leaky head studs are not what is going on. Maybe too much time on the head gasket? I don't think so... but I don't know.
 
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Will try putting sealant on all the studs, use a flat washer and re-torque heads as suggested hot/cold three times without coolant.

Thanks

Did you have the block tested before you rebuilt it ? Sorry if you already answered . What type of head gaskets ? Don't over torque!
 
Lots of good thoughts.
Couple of questions asked; the radiator cap is 7lbs., I torqued the head (aluminum) bolts to 40lbs. Not sure of what head gasket was used, I bought the motor completely assembled intake to pan. Had been assembled by a company in Dallas. I have all the specifications but doesn't indicate the gasket brand.
I think I will at this point I will remove the heads and try to see what's going on.

Thanks for the feed back.
 

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Lots of good thoughts.
Couple of questions asked; the radiator cap is 7lbs., I torqued the head (aluminum) bolts to 40lbs. Not sure of what head gasket was used, I bought the motor completely assembled intake to pan. Had been assembled by a company in Dallas. I have all the specifications but doesn't indicate the gasket brand.
I think I will at this point I will remove the heads and try to see what's going on.

Thanks for the feed back.

Good luck and please keep use posted .
Gary
 
May I ask which company in Dallas? Reason for the ask is that I am located just north of there and am looking for a rebuilder. Need to know who to stay away from.
 
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