AC 170 Oil Flowing Out Dipstick

[Andy682]

I am borrowing an Allis Chalmers 170 from someone and the oil is bubbling out of the dipstick once it gets hot. By bubbling I mean overflowing pretty steady, I had to add more oil to keep operating. None of the gauges work, but the tractor otherwise starts and runs strong. I'm prepared to change the oil in hopes it is a clogged oil filter, but does anyone know any other reason it may do this? I have no idea when the oil was last changed, and he didn't seem to either. Some general web searching is find a lot of possible reasons, but I'm hoping there may be some tractor specific knowledge here

 

[old]

I've hear of that happening due to a hole in a piston or real bad rings. I had a MH30 that when I started it to drive it to the shop the dip stick went flying and the engine died. Pulled the head off and #2 piston was AWOL as in got completely all that was there was the rod and wrist pin the piston was who know where

 

[Aaron SEIA]

Check the crankcase breather. I think it's on top of the valve cover. Could be so plugged it's building crankcase pressure.
AaronSEIA

 

[Andy682]

Yikes! Let's hope it's the breather I will check tonight. It seems to run smooth and have good, consistent power.

 

[DrAllis]

Talk about lack of information....ENGINE OIL DIPSTICK?? OR HYDRAULIC DIPSTICK OR TRANSMISSION DIPSTICK?? GASOLINE OR DIESEL???????????????????? IS THE RADIATOR FULL ???????????

 

[Andy682]

Good point Dr, funny how when I'm picturing it in my head those other elements are just there and oil seems to be most commonly referred to as engine. It's a diesel engine, and like the other guys correctly assumed, I am referring to the engine oil. The radiator appears to have plenty of coolant. And the hydraulic fluid appears to be satisfactory as well.

 

[DrAllis]

Are you sure you aren't gaining oil?? There is the possibility of diesel fuel getting into the oil thru the lift pump and/or injection pump to get the oil level overfull which would make the dipstick leak.

 

[DrAllis]

The breather is a hose that comes off of the valve cover. It cannot be plugged.

 

[Dieseltech]

That would be a Perkins diesel. If engine oil rises it and looks thin like diesel fuel it can either be the fuel transfer pump, and/or the injection pump drive hub seal. I'd start with the transfer pump first. I have been repairing more CAV DPA injection pumps due to drive hub seal leaking fuel into engine oil..

 

[4wdtom]

Is the oil level on the dipstick coming up or high? Is the oil thin? Does it smell like diesel fuel? If not maybe breather. If so a fuel leak as others have said.

 

[Andy682]

Follow up for future reference. I finally got around to servicing this tractor and the problem was the breather. As someone mentioned, this tractor has a tube coming from the top down below the frame and some mud dobbers did what they do best and clogged up that tube. Cleaned it out and the problem is solved. Thanks for everyone's input!