Many KA24e owners go through the dreaded ticking from faulty/seized hydraulic valve lifters (HVL). My engine was no different - especially as there was high mileage already on the drivetrain.
For those who don't know, the KA comes with hydraulic valve lifters (fancy words for an oil-pressurized valve lash adjuster) embedded within the rocker arms.
Best case scenario they dynamically adjust the valve lash making for a trouble-free setup. The problem is that over time most eventually fail and either seize shut (compressed) or do not maintain sufficient pressure causing a lot of play and hence the ticking.
It's pretty easy to find the faulty HVLs. Remove the valve cover and by pressing with just your finger (making sure the cam isn't acting on the rocker arm) you should have no more than 0.5mm of movement. In my case, I had one with 1-1.5mm and two others just over 0.5mm.
Finding replacements was a PITA. I eventually figured out that ordering full replacement rocker arms will include the HVL and remove the hassle of swapping them out. Rock Auto had them for about $32 each. An alternative is to go solid lash adjusters but that requires quite an investment in cash and maintenance.
To swap out the arms, which took all of 15min:
- Removed the valve cover
- Remove the rock arm shaft bolts from the outside - in.
- Carry the Shaft/arm assembly to a clean work bench
- Remove the spacer clips off the shaft, then the rocker arms slide right off the shaft.
- Soak the new rocker arms in an oil bath and then manually pressed the HVL when submerged. You will see air escape out of a bleed hole on top.
- Once bled I put them on the shaft, reinstalled the spacer clips, and bolted the shaft down. Working outside - in, starting with 15lbs/ft then repeating with 30 lbs/ft.
- I started the car and idled for a few minutes at 1500 RPM.
- They were still ticking a bit so I took the car out for a run. As soon as a load was placed on the engine the HVL quieted right up.