Rocker problem

[Seraman]

Ive replaced the head on my KE engine but have replaced the original (bigger valves) with a head that has smaller valves (already had so not ideal) with head number 219015. I know the original head was better but it needs all new valves seats valves etc and as the replacement head was already on the shelf ready to go it was fitted. The problem is that when fitted the adjustment of the tappets is not possible as the gap between the rocker and valve is way to big and there is not enough thread on the adjuster to close the gap. Possible causes are smaller valve length, shorter push rods or head dimensions different but all checks seems to show similar heights etc between both heads so Im at a loss. All I can think of is that the push rods are too short but is there any different heights etc between both heads?

[glang]

wow youre brave! I believe there all sorts of different head thicknesses and certainly different push rod lengths. Perhaps you can measure your existing rods and see how much longer you need and then give Rimmers or someone a call to see whats available. This chart is pretty useful as well:

https://www.chriswitor.com/cw_technical/head_applications_chart.pdf

[RobPearce]

Is yours an early or late KE engine? The heads are decidedly NOT compatible between them!

Early engines have flat-top pistons and need a low-height head to get compression. These are likely to be smaller valve as they were set up for the 2litre to get good air flow.

Later engines have dome-top pistons and need a significantly thicker head. This was done to commonise castings with the 2.5 and is sub-optimal for combustion chamber shape. They may also have over-sized valves (certainly the late 2000 saloon engine has valves that are too big for best performance) to match the mild cam fitted for emissions.

If you swap heads between early and late you will get messed up compression figures. I'm not even sure the early head wouldn't foul the late pistons.

[Gt6s]

Yup wrong head

[Seraman]

Ok a bit of info this is not the original engine it came in bits and I’ve rebuilt it from scratch but  as stated it is KE stamped. It must be an early one as it is none recessed and has flat top pistons. The push rods came with the engine and are 8 inch long exact. According to the data the 219015 should fit the early KE and having checked all measurements It measures up with the head that came off except for the valve head size all the stems and springs etc are the same measurements. It seems that the longer push rods would sort the problem but info on these longer ones say that they are for USA/Aussie derivatives. Anyhow to cut a long story short I have decided to overhaul the original head and dump the 219015 head although in theory as all the measurements add up it should fit with longer push rods.  just curious as to what was different on the head as the height etc etc are all  the same but it has to be the rocker shaft pedestal base that is thicker for some reason although it is flat with a straight edge across the rocker cover faces as the original head is also so no idea why longer push rods are needed . Why did they do longer rods originally? Moral of the story? Stick with known originals and also thanks for your input.