- Sun Dec 21, 2014 10:21 am
#42604
2nd thought if you re-route the oil away from the bottom of the barrels does this reduce lubrication to the piston skirt. Ed
Oversize tappet guides are available, OR you can copper plate the worn ones...
At best the return pump was designed to pump a mix of 50/50 air-oil. In reality the timing side only picks up 7/8s of SFA. Pretty much what oil there is, is dumped in there is from the rocker Oil pressure relief valve.
Now depending on your engine, and how original it is and or what may have happened to it over the years there are several variations to the oiling over the head and through the barrels into the sump.
Oil that drains down the inlet push rods mostly ends up running down the back of the bores and into the sump. Some drains into the timing chest. And if your oil level in the exhaust tunnel is flooded, (many are) then most of that oil also ends up in the sump, and not the timing cover.
Have a look at your barrels and the mouths of the crankcase and you should be able to see why…
Which is the primary reason why there is usually too much oil flying around the engine, and the poor old sump side is unable to cope. Hence the oil that is passed out the breather off the left side of the motor…
The more oil that you can direct away from the sump, the better the return pump is able to keep it clear of oil.
No, you have absolutely nothing to worry about with the pump sucking more air than oil; it was designed to work exactly that way.
Worried about not getting enough oil in the bottom of the bore?
Don’t be, aside from the fact that there is already too much oil being spun around the cases for the return pump to cope with.
The Interceptors (heaps more power) don’t have the lower barrel oil drillings. They return all the inlet rocker oil and pressure relief oil straight back to the tank and use both side of the scavenge to drain the sump…