it's pushing bubbles out of the line from the oil pump, and the sump is full - air is being sucked in - strip it
TheMiniMan wrote:
ah,,, we`ve been using STP for more than 40 years, me , my dad, all our mechs (probly more than 40 mechs that have come through our workshops over the years) Robbo & his mechs & there`s plenty plenty more who also swear by it also
not one broken pump drive from using STP,,, period
i`d imagin that`s well into the "Thousands" of engines we`ve collectively built using STP
I took your advice on that Matt with my last 2 engine builds (mine and one for a mate) and it worked a treat. The last one I also mixed moly grease in with the STP and used it as assembly lube. Made the most beautiful black sticky goo

peterb wrote:
I take out the oil pressure switch and using a bit of 3/16" rubber vacume hose and oil can, pump as much as you can in. Works every time for me.
I do that also, but with a 1l pressurised oil tank- fill the tank up with oil, then pressurise it with the compressor and blow it through - oil comes up through the rocker shaft