Forum:
Hello Everyone.
I hope someone can give me a little advice on my Hijet 993 CB42.
I changed the head gasket and skimmed the head. When I put it all back together
The engine runs fine but there is a Knocking/rattle/tapping sound as if the valves are not adjusted correctly. I have double checked them and they seem ok.
My big fear is that the head might have been skimmed to much causing the valves to bang against the pistons.
Any ideas or advice would be very welcome.
Thank you.
Paul.
Yes they do run very close on
Yes they do run very close on some Daihatsu engines and in the workshop manual skimming head is not allowed on some.
But also worth a mention, The valve clearances on Daihatsu's are often only quoted for a HOT engine. So if the head has been rebuilt and valves set when cold (using the hot settings) It will sound tappy as hell.
As a rule of thumb, subtrack 0.10mm from the hot setting if you want to adjust valves cold (alloy head with cast iron block)
Thanks for a quick reply, I
Thanks for a quick reply, I will redo the valves and see if it helps.
Fingers crossed.
Ps. Do you mean make the gap 0.1 less or more
Adjust less gap. For
Adjust less gap.
For example, Inlet valves maybe listed as 0.27mm Hot.
So adjust down to about 0.15mm-0.17mm when cold
With over head cam engines, The valve gap becomes wider with engine heat.