Part 7 - Component by Component

15. Head gasket

Must be standard and unmodified and will at all times have a minimum thickness at all points of 0.88mm when used on K, E and T1 engines.  Alternatively these engines can use 4 off gasket part number 12251-ZLO-003 which, when measured together at all points, must have a minimum thickness of 0.80mm.  The T2 engine will use one off part number 12251-ZLO-003 which, when measured at all points must have a minimum dimension of  0.20mm.

6. Piston

The dished piston must only be used with the cylinder head from the K type engine. The flat-top pistons are interchangeable between the E and T1 type engines only and must not be used in the K type engine or with the K type head. Piston rings will be standard unmodified.

Only standard size rings, (marked 1R, R, T, 1T, NT, 1N/T or N on top ring) can be used. Either the single or three-piece oil control ring can be used on all engine types. The rings must always be free in their grooves and function as designed. T1 and T2 pistons are not interchangeable. The T2 piston is shorter and has an additional curve under the oil ring. The top two piston rings are visually similar to the T1 but the oil control ring is thinner (2mm as against 2.5mm on the T1) and the ring groove in the piston is correspondingly smaller. All dimensions on the T2 piston must comply with the ABkC piston gauge (see Appendix 2).

Piston early T1Piston late T1Piston T2