TR7 engine "breather" problem

[justincaton]

hi
i have been chasing a air / oli leak around my engine all winter - TR7 2.0ltr v4

now i have oil / smoke from the dip stick pipe

I have checked all pipes and breather (i.e. metal and rubber pipes from carbs to rocker cover)

have i missed something or is it worn pistons and engine out ? :-(

thanks for any help

Justin - DK

[tapkaJohnD]

An engine crankcase normally has a positive presure in it, due to blow by from the piston rings. The usual venting to the intake or a catch tank takes car of the combustion gases and oil vapour. If that cannot cope because it's blocked or the escape is excessive then pressure will rise and oil leaks appear.

Try removing the oil filler cap frm the rocker cover once the enegine is warmed up and idling. Does the oil leak from the dip stick stop? It will! Is there a mild zephyr of a breeze coming out of the filler hole, or a mighty wind? More than the first indicates excessive blow by. Further check, compression test. This will tell you if there is one piston, or pistons, whose rings are failing, by a reduced pressure compared to the rest.

Could just need new rings. Only measuring the bore will tell you if a rebore is needed.
JOhn