I have an International 7500 with the HT 530 engine and I am noticing that when I idle it in the driveway that there is a little bit of oil coming out of a rubber tube that is coming out of the bottom of the engine. There is also what looks like exhaust coming out of the tube as well. I am not shure what this tube is for as I know very little about diesel engines. Is this a breather tube? Should I be alarmed if I see oil and exhaust coming out of it? What is this an indicator of? The engine has 460,000 miles on it and should not be ready for an overhaul yet. Need some input as I just recently bought the truck and it is still under warranty. What should I tell them to fix if I take it in? Thanks.
Oil in the Driveway
- Thread starter gavinsdad
- Start date
rode2rouen
Expert Expediter
What you are seeing is residual oil from the road draft tube. The road draft tube allows the crankcase to "breathe" as the pistons do their up and down thing inside the engine. It also allows the "blow by" (combustion gasses that pass the piston rings) a vent to atmosphere so pressure doesn't build up in the crankcase and blow out gaskets.
A small amount of oil is no big deal...let's say a puddle the size of a 50cent piece.
Rex
A small amount of oil is no big deal...let's say a puddle the size of a 50cent piece.
Rex
dieseldoctor1
Expert Expediter
If you are getting oil out the breather tube you are probably getting close to needing an overhaul. I would take it to an International dealer and have them check the crankcase pressure with a manometer. It will check the pressure in inches of water pressure and they have specs to go by. International dealers are probably the only shops that will have the special adapter that MUST to be used to get an accurate reading.
Those engines normally run high crankcase pressure (a lot of vapor)but it shouldn't carry oil out with it. That's why you need the test to get an exact figure and compare it to the specs.I agree your engine shouldn't need overhauling yet but you never know how it was mantained in the past. If the owner changed the air cleaner too often or incorrectly, then the rings could have been damaged by dust. Does the engine use oil? If not and the power is good you have to decide if the small amount of oil out the breather bothers you enough for an overhaul.
You mentioned it still being in warrenty so you may want to try to force the issue and get them to pay for at least part of the overhaul. Get a seperate International dealer to check the crankcase pressure though. Have them record the readings on the workorder so you have something in writing to show the dealer that sold you the truck. Good Luck!
Dieseldoctor
Those engines normally run high crankcase pressure (a lot of vapor)but it shouldn't carry oil out with it. That's why you need the test to get an exact figure and compare it to the specs.I agree your engine shouldn't need overhauling yet but you never know how it was mantained in the past. If the owner changed the air cleaner too often or incorrectly, then the rings could have been damaged by dust. Does the engine use oil? If not and the power is good you have to decide if the small amount of oil out the breather bothers you enough for an overhaul.
You mentioned it still being in warrenty so you may want to try to force the issue and get them to pay for at least part of the overhaul. Get a seperate International dealer to check the crankcase pressure though. Have them record the readings on the workorder so you have something in writing to show the dealer that sold you the truck. Good Luck!
Dieseldoctor
arkjarhead
Veteran Expediter
if the tube you are talking about is hanging straight down towards the front it is you blowby or engine exhaust. exhaust coming out of the is perfectly normal.
It is 100% normal to see the vapor and a little bit of oil drip from the crankcase vent tube especially while idling after running at high speeds. Cars have had a system called PCV (Positive Crankcase Ventilation) that sucks the crankcase vapors back in to the intake to be burned again, but big diesels have been allowed to vent the unburned fuel blowby and water vapors in to the open air still. Rex said it right. Mudflap