Skip the auto shop - Our mechanics make house calls
  1. Home
  2. Articles
  3. Symptoms of a Bad or Failing Crankshaft Seal

Symptoms of a Bad or Failing Crankshaft Seal

crankshaft seal

The crankshaft seal is the seal located on the front of the engine that seals the end of the crankshaft with the timing cover. Most crankshaft seals are made of rubber and metal and are round in shape. They are usually installed in the front timing cover and seal the end of the crankshaft as it rotates. While they are a relatively simple component, they serve an important purpose in keeping the oil that is constantly being used and tossed by the crankshaft as it rotates from leaking out of the engine’s crankcase. When they fail they can cause leaks which can make a mess, and if left unattended, can put the engine at risk of serious damage. Usually a crankshaft seal will display a few symptoms that can alert the driver that there may be an issue that should be serviced.

High mileage

If your vehicle is approaching high mileage, perhaps upwards of one hundred thousand miles, then the crankshaft seal may be approaching the end of it’s recommended service life. All manufacturers have a recommended service interval for most of the components on a vehicle. Servicing the crankshaft seal according to the recommended service interval can prevent the seal from failing in the first place, which can cause other problems.

Oil leaks

Oil leaks are the most common symptom of a problem with the crankshaft seal. If the crankshaft seal dries out, cracks, or breaks, it can cause an oil leak. Small leaks can cause oil to accumulate on the undersides of the engine, while larger ones may produce a drip of oil from the front of the engine.

The crankshaft seal is mounted behind the engine’s main crankshaft pulley, so servicing it requires the removal of the belts and crankshaft pulley and harmonic balancer before it can be accessed. For this reason, if you suspect your crankshaft seal may be leaking or near the end of its service life, have the vehicle inspected by a professional technician, such as one from YourMechanic. They will be able to look over your car and determine if it needs a crankshaft seal replacement.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Still not sure about your car's issue?
Diagnose your car
What kind of issue are you experiencing?
Brakes are squeaking
Car is not starting
Car is overheating
Car is shaking (vibrating)
Fluids are leaking
Heating and A/C
Smoke or steam is coming out of the car
Warning light is on
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

P0222 OBD-II Trouble Code: Throttle/Pedal Position Switch/Sensor B Circuit Low Input
P0222 code definition Throttle/Pedal Position Switch/Sensor B Circuit Low Input What the P0222...
How to Transfer a Car Title in Idaho
In order to prove ownership of a car, you must have the title. However, when a car is sold, given away or inherited, the title needs...
How to Get a Louisiana Driver's Permit
s licensing program. The first step in this program is to obtain...


Related questions

Q: I can't get my bike to roll in gear when the clutch is pulled.

Try adjusting the clutch cable until you have very little free travel before it starts to pull the clutch in. You should be okay then to put it together and start the engine in neutral and exercise the clutch in...

Q: I have 16 valve stem seals and then 15 other little things

The valve cover on your engine is held on by 15 bolts. In certain applications, grommet seals, 15 of them, were used along with the bolts. However, rubber grommets were used as seals in only certain applications. Upon disassembly if...

Q: Water leak on the passenger floorboard w/defroster and AC running.

If the leak does not contain any antifreeze or other "engine coolant" AND the leak is not due to A/C condensate backing up (if the A/C is working, just check for flow of condensate onto the ground or if this...