6v92 detroit coolant in oil?

[Vetech63]

Your best bet would be to drain the engine oil, top off your radiator, and pressurize your cooling system. It would be ideal to have the oil pan off the engine so you can see where the coolant is coming from. At least it would help you narrow down a specific area of concern. You are correct in that the upper liner area is wet sleeved (meaning antifreeze makes direct contact with the liner) and the lower part of the liner is dry sleeved. Leaks at the liner orings generally have antifreeze in the air box which is normally drained through the air box tubes to the ground providing they are not plugged up. Leaks at the injector tubes on the tip side usually end up in the airbox also depending on the position of the piston in the liner. I have found more times than not that these leaks accumulate antifreeze to create a hydraulic lock when trying to start the engine which ends up in a bent connecting rod. There is orings under the top side of the injector tube outer flange that can leak also.....you would see this with the valve cover removed and the cooling system pressurized, in which the antifreeze would go straight to the oil pan. Leaking head orings usually go straight to the oil pan. An intercooler under the blower can leak antifreeze but that also usually ends up in said airbox.

If you have found no antifreeze in the airbox at all, then I would first suspect the water pump itself. They can leak water from the driver shaft side straight into the oil pan. JMHO of course.

 

[kshansen]

Your best bet would be to drain the engine oil, top off your radiator, and pressurize your cooling system. It would be ideal to have the oil pan off the engine so you can see where the coolant is coming from.

If it is possible to get the pan off that would be an excellent idea.

I would be tempted to start by pulling the valve covers and look in there.

Next maybe remove at least one airbox cover on each side to see if there is any signs of coolant there, coolant runs down hill so if one end of engine is lower than the other remove cover from lower end.

And if you have not already started the engine I would not try that until you are sure where the coolant is coming from and going to, bent rods are not a good thing! If you must start I would suggest turning over a couple turns by hand to besure you do not have a hydrostatic lock condition.

 

[nodwell]

Thanks again for all the terrific advice!! I don't need to start it, since 6v92 just runs the blower. The truck is driven by a smoking 471. Pan can certainly be pulled with some "remodeling." If I don't update you all right away it's because my day job is a rancher and we are going to be calving soon. I really appreciate everyone's generous advice and help!!

 

[kshansen]

So looks like you maybe using one of these for a while:
https://www.ebay.com/bhp/calf-puller

 

[DMiller]

We only ever had chains and come alongs.

 

[DMiller]

Emeryville con queen cab. Mid sixtyish? The w/p is a whole lot easier to rebuild OFF the engine.

 

[kshansen]

The w/p is a whole lot easier to rebuild OFF the engine.

My thoughts too. And looking at the upper hose on that pump I'm thinking replacing the hoses to the pump would also be good insurance no matter what!

But let's not forget we still need to find the source of the leak and not just start shooting at the hip replacing things! Would sure suck to pull that pump and rebuild it and put it back on and find out the leak is a bad o'ring on the top of an injector tube and have to tear the engine back apart again.

 

[lg junior]

Pull the valve covers before you do anything else.Ive had three detroits that had injector tubes leak. Easy to see the problem, not an easy fix. The weep holes on the back side of the pump, hard to see but my thought is that's not he problem. I've never had a water pump seal leak to oil. I have had them seize up and break shafts and lose the impeller and leak out the weep hole but never lose both seals.
Good luck keep us posted!

 

[nodwell]

We hope to not use a calf puller too much. I haven't used it at all for at least a couple of years. The cab on the truck is an international. I think the running gear is supposed to be a fwd. Supposedly, a fella from North Dakota bought it out in Idaho and when he fixed it up did a cab swap. I hope I can get time to pull the valve covers before the calves start coming fast. Thanks so much for all the terrific advice!!

 

[kshansen]

The weep holes on the back side of the pump, hard to see but my thought is that's not he problem. I've never had a water pump seal leak to oil. I have had them seize up and break shafts and lose the impeller and leak out the weep hole but never lose both seals.!

Won't say it is common but did have a coolant in oil problem on a 16V-71 that I spent most of a day watching with air pressure in radiator trying to find source of leak.

Four valve covers off watching 16 injector tubes, looking down oil drain holes in four heads dropping oil pans, yea two sumps on that engine, not a drop seen anywhere. Nothing out of air box drains that were checked to be open.

Left for the night and came back in morning to see a trail of coolant across the shop floor. Followed it back to truck and see it coming down from front right side of engine. Shine flashlight up inside and drips coming down the inside of the front cover right below the water pump. No other water near that point so knew it had to be the pump.

Removed the pump and find the weep hole plugged solid with mud dauber crap! For some reason the pressure on the coolant had actually helped the water seal block the coolant but when pressure was off it leaked!

 

[nodwell]

The 16v-71's look like really sweet engines!! I wish I had an excuse to get one! LOL!

 

[wornout wrench]

I have had much the same findings as Kshansen.
When I was a younger man, everything we had was detroit powered.

While it was not a common failure, it did happen so it was one of the first things we looked for when we found coolant in the oil.

 

[kshansen]

While it was not a common failure, it did happen so it was one of the first things we looked for when we found coolant in the oil.

And not just with Detroits, recall at least a couple 3306 Cats that had the same problem.

I would say any gear driven water pump is susceptible to those dang bugs sealing up weep holes. Just wish the designers took that into account and put the weeps in an easy to see and clean out position!

Now that I'm thinking, second cup of coffee kicking in, recall I believe it was Cat that came up with the idea to put a little foam filter in some weeps holes. Another brilliant idea that probably looked great on paper! Who would have guess water and dust would seal off the pores in that foam plug?

 

[DMiller]

Kind of like the old compressed bronze fiber fuel and hydraulic tank vents that would seal off from goo accumulation!

 

[kshansen]

Kind of like the old compressed bronze fiber fuel and hydraulic tank vents that would seal off from goo accumulation!

Yea. they have a JD back-hoe at the quarry and a couple times a year I would be told there was a problem with it, no power hardly able to climb hill out of the pit. Remove fuel cap and flush out that bronze vent and runs like new engine!

 

[nodwell]

Finally found the w/p weep hole. LOL. Don't think it was plugged, but did try to clean it some just to make sure. I'm assuming the weep hole lets any coolant drain that gets by the water seal in the pump to protect the engine??? Therefore, if it's not plugged there's approximately a 98% chance the coolant in the oil is not coming from the water pump??? Is this correct??? Hopefully, I can get the valve covers pulled before too long. Good thing I bought a radiator pressure set at an auction a couple of years ago. Thanks for your help!!

 

[nodwell]

 

[DMiller]

That's a wicked looking machine.