I have a 1.3 Skoda 136 engine in my felicia rally car, and the engine has just been rebuilt, retaining the previous Piper 285 Cam profile (timed to 108 degrees, as pre-rebuild), but with the addition of a new cylinder head and increased compression ratio (up from 10:1 to 11.5:1). This engine has been run in for a few hours and was running well, but had not been dynoed; I am running a wideband O2 meter on it and a logging setup and the fuelling has been correctly set, but the advance is currently not set up and has been set conservatively less than the previous (dyno-set) settings, awaiting a dyno run.
However, on Saturday the engine started to run poorly, feeling like it was semi-missing on one cylinder, and a compression test showed cylinder 1 to only be compressing to 6 bar, while the others were at 13 bar. As I've had to remove the engine and gearbox to replace the input shaft oil seal on the gearbox, I removed the head, and found that the head gasket looked to be in very poor condition - on one side of the cylinders only, with all four cylinders affected by this, but looking clear where No.1 was losing compression; the liner protrusions are still within spec, and examination of the gasket shows that they have left a good impression on it, but the appearance of it worries me; the pistons and head are both in good condition. Cylinder head gasket was a pattern one (due to postal damage of the OEM one, and my error for not waited another week, I guess), but i have OEM (Temac) ones here now. Cylinder head is unwarped.
Looking at the photos of the head and the gasket, is there anything you can suggest or recommend?
- Marking on head from gasket failure?
- skoda_head_fail_1.jpg (24.05 KiB) Viewed 4722 times
- Cylinder Head Gasket
- skoda_head_fail_2.jpg (19.06 KiB) Viewed 4722 times
- Cylinder Head Gasket, No.1 cylinder
- skoda_head_fail_3.jpg (20.02 KiB) Viewed 4722 times
Darren