So yesterday I finally got round to refitting the valves which I had reground in the head of the spare engine I'm rebuilding.
Thought it would be prudent to do a wet leak test so inverted the head and left it over night with each chamber filled with liquid WD40. Looked at it his morning and found that each chamber was still fairly full but nearly all of the ports had some seepage.
Now to my mind considering that valve seats are a metal seal and thus not a perfect seal this is to be expected or am I wrong?
Did you have the seats and valves ground, or just the valves? I ask, 'cos the seats are not designed to be ground.
If it was just the valves, did you lap them in?
They should hold petrol back, so WD 40 should stay put.
Hi Carolyn, sorry, when I said ground I really meant lapped (both coarse and fine) as they were in quite good shape.
Currently I've cleaned out the WD40 and trying them with petrol which seems better but looks like I may have to do some more lapping :(