Rocker arm oiling

[loon]

I am rebuilding a KA24E. I have always had problems with rocker arm tap with this block, even changed heads last rebuild, same problem. It would be fine sometimes but then would start tapping like a sewing machine. I was wondering if anyone has tried enlarging the oil hole in the block for the rocker arms.

[loon]

bump

[dcino]

Depending on your mileage, your problem might stem from worn lifters.pull the cam and clean the oil gallery with pipe cleaners, soak the rocker arms in wd40 and be sure the lifer plunger will actually move.I think that there is a tech article in this system that explains how to re-work these but I have not had much luck doing this.On several sohc engines I have found the bolts on the rocker arm standoffs have been stripped and allow the rocker arms to clatter when the cam flexes.I've found some springs that add about 10lbs to the exhaust valves which seem to be the ones that make noise first.(this usually only happens if you have reworked the PCM and taken off the rev limiter)If you have a really hi mileage unit you just need a new oil pump.good luck