I have my EJ205 out of my 2003 WRX. I pulled the engine in the first place to troubleshoot a 90% pressure loss in Cylinder 4 (measured via a leakdown test with the Engine still in the car). The remaining cylinders all had ~5% pressure loss. After removing the heads, I found that Cylinder 4 had a burnt out exhaust valve. I took this opportunity to replace:
- All intake/exhaust valves (lapped)
- All valve springs
- All valve stem seals
- Ordered new bucket cover (shims) to put all valves in spec
- New head gaskets on head install
After putting the heads back on, getting the timing belt together, and valve covers on, I decided to run a leak down test while the engine is out and before I do any further work.
Here are the results of the leak down test, each cylinder couldn't exceed 75 psi. Using an endoscope, I put each cylinder to TDC for each test:
- Cylinder 1: leaks ~90% pressure loss from intake valves
- Cylinder 2: leaks ~25% pressure loss from both intake and exhaust valves
- Cylinder 3: leaks ~25% pressure loss from exhaust valves
- Cylinder 4: leaks ~25% pressure loss from exhaust valves
This is the second time I've done a valve job and I'm a bit alarmed. Did I mess things up that bad? Is excessive leaking on a new valve job (with engine outside of car/before first start up) expected?
My first guess might be the timing belt? After installing the timing belt and engaging the tensioner, I verified that all the timing marks lined up. Any other theories before I remove the heads again?
Edit: Verified timing belt is aligned correctly.