The fuel pressure from the injector rail cast into the head (small hole to the left of the arrow) is far greater than the pressure in the cooling system. When a crack occurs, diesel fuel easily passes into the coolant.

What causes diesel fuel in coolant?

The fuel pressure from the injector rail cast into the head (small hole to the left of the arrow) is far greater than the pressure in the cooling system. When a crack occurs, diesel fuel easily passes into the coolant.

Why does my coolant smell like diesel?

if you coolant smells like diesel you have a cracked head not cup and here is one of the ways you can fined it or a leaking injector. take the head with injectors and rail everything together put it in a tub of water and apply air.

What does it mean if there’s oil in the coolant?

If there is oil in your coolant or vice versa, it generally means there is a failure in one or more of your engine’s gaskets or seals. Your engine is designed so that there is one system that controls engine oil to lubricate your vehicle and another that manages coolant to keep your car from overheating.

Why does my coolant reservoir smell like gas?

Fuel smell in the radiator without a cloud of steam usually indicates a head cracked in or around the exhaust port, since this area is almost always under some kind of pressure and won’t allow much — if any — water to enter the exhaust stream.

Why is there oil in my coolant but no coolant in my oil?

When the engine cools and the cooling system goes into a vacuum, small amounts of oil are drawn into the cooling system from around the gaskets. When the engine is restarted the cylinder heads and intake manifold expand faster than the cooling system pressurises so no coolant leaks into the oil.

What does gas in the coolant mean?

Exhaust gases in your engine’s coolant are usually a sign of a blown head gasket or cracked cylinder head. Continuing to operate your vehicle in either of these cases will quickly lead to full engine failure. If you suspect you have either of these issues, you should perform this test immediately.