How do you inspect a camshaft?
How do you inspect a camshaft?
Inspect the camshaft cam faces and bearing journals for roughness or obvious excessive wear. Measure the cam height with a micrometer, taking measurements at the outer edge of the cam on both sides. The surface of the cam must be clean to ensure accurate readings.
What is cam spalling?
After this process starts, the constant pressure between the cam lobe and lifter wears off more and more material even though the engine is being lubricated during operation. This process is referred to as “spalling” of the lifter. The removed material and the rough lifter face will eventually wear the camshaft lobe.
What causes camshaft pitting?
In many cases, pitting on the lobes is due to normal part wear from many hours of operation. Even so, it’s important to identify and replace before the camshaft fails completely or causes damage to other components due to improper operation. In other instances, the pitting might be caused from debris in the components.
Do camshafts fail?
A broken camshaft is usually caused by a connecting rod or other rotating part coming loose and striking it. Sometimes the cam will break after a short time of use because of a crack or fracture in the cam due to rough handling during shipping or improper handling prior to installation.
How do you know when a camshaft is bad?
To help you prevent all of this, here are common camshaft wear symptoms to look out for:
- Active check engine light.
- Loud ticking or tapping sounds.
- Metal debris in the engine oil.
- Cylinder misfire.
- Increased emissions as a result of misfiring.
- Visible signs of damage.
How do I know if I have a bad camshaft?
1. Vehicle does not drive like it used to. If your vehicle idles roughly, stalls frequently, has a drop in engine power, stumbles frequently, has reduced gas mileage, or accelerates slowly, these are all signs your camshaft position sensor could be failing.
What happens when camshaft goes bad?
A vehicle with a damaged camshaft may suffer from reduced engine performance due to cylinder misfire. Your vehicle may hesitate and lose power, jerk or shake aggressively, consume more fuel than usual, and produce more emissions.
How do I know if my camshaft is bad?
What can damage a camshaft?
A cracked camshaft.
- Excessive Wear. This usually refers to cam lobes wearing out too quickly.
- Mechanical Interference. When moving parts are not given adequate clearance, things can start to break.
- Broken Pieces. In some cases, the dowel pin (or key) will break off the end of the camshaft.
- A Cracked Camshaft.
Where is the camshaft located on a Lycoming engine?
The camshaft on Lycoming engines is located in the top of the crankcase above the crankshaft. Its position in the top of the case means that oil drains off it first once the engine is shut down. On Continentals, the camshaft is located beneath the crankshaft, but it is still above the oil sump and residual oil eventually drains off it as well.
What kind of lifter body does a Lycoming O-235 have?
A lobe on a Lycoming O-235 camshaft that has been damaged from a spalled lifter. The spalled and corroded lifter face. Most Continental engines use cylindrically-shaped lifter bodies that can be removed without splitting the crankcase. Lycoming engines use mushroom-shaped lifter bodies that have a larger diameter at the face of the lifter.
How do you check if a camshaft is still airworthy?
Continental Service Information Directive SID 05-1B contains inspection criteria which should be used to determine if a camshaft is still airworthy. Continental recommends using a mechanic’s pick to probe any surface deformities. If the pick catches, the camshaft most likely will need to be replaced.
What are the parts of a Lycoming valve train?
The valve train components: camshaft, lifter, pushrod, rocker arm and valve. A solid Lycoming O-235 lifter. The lifter consists of a cast-iron outer body that houses a hydraulic unit. There are a couple of Lycoming engines that still utilize solid lifters with no hydraulic unit, but the vast majority of engines have hydraulic lifters.
