MACK MAN Posted July 14, 2008 Share Posted July 14, 2008 I have a 1959 Mack B81 with an END 673. Pulled out the dipstick today to check the oil and found antifreeze. I pulled off the valve cover and definitely have water in the oil. According to the Mack service manual, it could be one of several things. (1) Defective oil cooler core (2) defective water pump oil seal (3) blown head gasket. I've always assumed water in oil was a blown head gasket. Any advice? There is no additional guidance in the service manual to determine which of these three things it might be. I hate to pull the heads off if its an oil cooler core - anyone have an idea to figure out which of these it might be?Thanks,Al Quote Link to comment Share on other sites More sharing options...
HK Trucking Posted July 14, 2008 Share Posted July 14, 2008 Does your engine even have an oil cooler?I had a 1958 B81 with a 673 and it did not have an oil cooler.That said, an oil cooler if present would be the most likely source of oil getting into the coolant.Leaking head gaskets could cause it also, as could an air compressor with a blown head gasket.The water pump would not be a source of engine oil in the coolant, as the water pump bearings are packed in grease, not lubed by engine oil. Quote "If You Can't Shift It Smoothly, You Shouldn't Be Driving It" Link to comment Share on other sites More sharing options...
Rob Posted July 14, 2008 Share Posted July 14, 2008 Does your engine even have an oil cooler?I had a 1958 B81 with a 673 and it did not have an oil cooler.That said, an oil cooler if present would be the most likely source of oil getting into the coolant.Leaking head gaskets could cause it also, as could an air compressor with a blown head gasket.The water pump would not be a source of engine oil in the coolant, as the water pump bearings are packed in grease, not lubed by engine oil.Herb, Al has coolant in the engine oil, not the other way around as written. Could very well be the oil cooler heat exchanger has broken a seam internally and is a factor in the problem. A 1959 truck with an oil cooler would be rare, but not impossible if not added later, or an engine change.Al, if you have an external oil cooler; Remove it, find a way to plug the inlet, or outlet of either the oil section, or coolant section. Apply compressed air to the other end while the cooler is submerged in water with about 30 psi. Any leaks will appear as bubbles. Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment Share on other sites More sharing options...
HK Trucking Posted July 14, 2008 Share Posted July 14, 2008 Herb, Al has coolant in the engine oil, not the other way around as written. Could very well be the oil cooler heat exchanger has broken a seam internally and is a factor in the problem. A 1959 truck with an oil cooler would be rare, but not impossible if not added later, or an engine change.Al, if you have an external oil cooler; Remove it, find a way to plug the inlet, or outlet of either the oil section, or coolant section. Apply compressed air to the other end while the cooler is submerged in water with about 30 psi. Any leaks will appear as bubbles. RobGuess my dyslexia must be flaring up.But actually the same factors which would cause oil in the coolant could also cause coolant in the oil. Quote "If You Can't Shift It Smoothly, You Shouldn't Be Driving It" Link to comment Share on other sites More sharing options...
Rob Posted July 14, 2008 Share Posted July 14, 2008 Guess my dyslexia must be flaring up.But actually the same factors which would cause oil in the coolant could also cause coolant in the oil.You're getting more like me everyday.......I agree with your diagnosis. Most times I've seen oil in the coolant, it has been related to an external cooler failure. The higher pressure of the oiling system overcomes the lesser coolant pressure and attempted equalization takes place with the transfer of fluids.Most everytime I have seen coolant in the oil, it has been related to the cylinder head(s). This is of course due to cracking, or blown head gaskets. Never seen an air compressor cause this symptom myself, but I'm certain someone with more experience has several times.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment Share on other sites More sharing options...
ciw65 Posted July 14, 2008 Share Posted July 14, 2008 You're getting more like me everyday.......I agree with your diagnosis. Most times I've seen oil in the coolant, it has been related to an external cooler failure. The higher pressure of the oiling system overcomes the lesser coolant pressure and attempted equalization takes place with the transfer of fluids.Most everytime I have seen coolant in the oil, it has been related to the cylinder head(s). This is of course due to cracking, or blown head gaskets. Never seen an air compressor cause this symptom myself, but I'm certain someone with more experience has several times.RobYep, our E-tech did it. When I did the in chassis rebuild down the pit doing the bearings I felt dripping down my neck, figured it was oil so ignored it. Then got a drip on my glasses and could see through it so gulped and went Oh dear, this doesn't look good. You know that feeling, sump off, heads off, liners out, cooling system drained and you still got water dripping. So investigated and found water dripping from under the cam. Now this just isn't right! Near climbed inside the crankcase at this point and found it coming from a "hole" in the block. The compressor mounting hole that is. Got fingers in there and found water in the compressor drive adapter housing. Pulled compressor head off and found water tracks to both cylinders from water jackets in the head. Was a first for me, but lesson learnt, Never say never! Quote Link to comment Share on other sites More sharing options...
theakerstwo Posted July 15, 2008 Share Posted July 15, 2008 As already been said cant be the water pump but pull the oil pan and pressure and you may find it but dont over look the ideal of a hole in the block about 2 inches up from the bottom betwwen the liner and block on the air compressor side due to electraices or somthing like that . Those engines due to their age was known to do that. Even a 675 or 711 will do that . It can be repaired and i think i could tell you of some one you know that i repaired one for about 5 years ago and it runs ever day and i ran with it to day. glenn Quote glenn akers Link to comment Share on other sites More sharing options...
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