453 Detroit Fuel In Oil - Diesel Forum

smttractor · 10-15-2009, 11:58 AM

I have a 453 detroit on a 1970 international 1700 truck (factory engine). Recently I noticed oil level over full and determined it was diesel fuel. I checked the lift pump and found no problem. I removed the rocker cover and plugged the return line and actived the pump with a drill and could not find any leaks on the lines or aound the injectors. The engine has many miles on it and smokes blue smoke quite a bit when cold and black smoke when loaded hard. I am not looseing any coolant. Can the injectors be bad and leaking causing this?

aekrogh · 10-15-2009, 12:57 PM

I had a similar problem on my 6V53 it was a bad injector tip/plunger. It was stuck to were there was always a small amount of fuel dribbling into the cylinder......did not find mine soon enough and had to resleave the one cylinder. If the motor is running and you put your hand on the exhaust manifold (like when you first start it in the morning) look for the cylinder that is putting out less heat than the others. That is the injector that i would pull first. Let me know what you find.

smttractor · 10-15-2009, 01:24 PM

Thanks. I will give that a try.

Gone Fishen · 10-15-2009, 11:04 PM

Plug off the return line to the tank, install a hand pump and pressureize the fuel system AFTER the fuel pump to 70 psi. The leak will show up. Usually a damaged jumper line or a loose line under the rocker cover. I have also seen the 3/8 washer under the fuel line connector at the top of the head leaking. Remember AFTER the fuel pump. ANy pressure greather than 15 lbs at the fuel pump will blow the seals out.