The Rocker arms are guided by a steel support witch is cast en bloc with the zylinder head.
Later models came with a aluminium cylinder head. On the aluminium cylinder head, the support is screwed on the head.
Around the outlet valve is a lot of residue of combustion. Maybe this is the reason for the low compression?
The outlet valve in detail.
The inlet valve in detail.
In driving direction from left port.
In driving direction from right port.
Here you cann see, that the rust remover is flown between valve and valve seat.
Combustion chamber after cleaning.
Before cleaning, i put some rust remover into the combustion chamber with closed valves. After a view hous, it was easy to clean the combustion chamber (with closed valves).
After cleaning it was possible to turn the outlet valve in the seat without any tools. Which means, that there was a gap between valve and valve seat.
Probably there was some debris of combustion on the shaft of the valve, which blocks the valve from sliding back onto the valve seat.
On the inlet valve was no turning possible without tools.
This is the seat of the outlet valve after cleaning.
On the color of the seat you can see, that the valve has no contact to the seat due to the residue of combustion.
This is the seat of the inlet valve after cleaning.
The valve guide looks bad.
Between vlave and guide is also a lot of space.
On the picture are all the parts, which belongs to the inlet valve.
There is a cap on the picture, which is only used with the old valves. The old valves are not hardened at the end of the shaft, so they put a hardened cap. New valves are already hardened. So donīt use the cap. Compare also the lengh of the valves. They must have the same lengh, as the old ones with the caps.
On the edge of the cone, where the valve contacts the valve seat, is not enough material for a new seat grinding.
On the picture are all the parts, which belongs to the outlet valve.
On the color of the cone you can see, that there was no cantact to the cone seat.
The material of the valve guides is not suitable for a cast iron cylinderhead.
On a cast iron cylinderhead cast iron valve guides should be used.
Also it turned out, that the new inlet valve was 1mm greater in diameter, than the old one.
So i have bought new guides and trimmed the new valve to the original diameter.
I have bought the first parts by a known Horex dealer, trusted on his expert knowledge.
But: Trust is good, control is better!
New inlet valve in detail.
New outlet valve in detial.
The new iron valve guides were mounted by using liquid nitrogen to shrink them, before placing them into the head.
After this i have to bring them to size, by using a expanding reamer.
The vlave cones were revised and the valves grinded in.
I covered both sides of the head to protect them from sand blasting.
Here the cylinderhead after sandblasting and painting.
The new valves are already mounted.
