Blue smoke out the tailpipe keeps people from getting right up on my
rear end to see "what kind of car is it?" I have a no-lead head and the
generous tolerances needed for the bronze valve guides contributes to
the smoke.
Mike MacLean
60 Sprite
56 BN2 (Just back from the sandblasters!)
Guy Weller wrote:
>Brad,
>I guess there are tollerances quoted somewhere for rocker shaft wear. On
>mine the shaft had distinct wear ridges, and the case hardening was breaking
>down in high pressure areas. If you start the car with the rocker cover off
>you can see just how much oil is leaking out from the rocker bushes. I got
>another shaft from the local scrap yard which looked a lot better and had
>very little wear. It certainly slowed down the excessive flow of oil.
>
>In theory, the exhaust valve stems should not suck oil down them as when the
>valve is in the open position, the piston is rising to dispell exhaust
>gasses. Opposite of the inlet valves which suck - if you get my drift.
>However, it may have something to do with valve overlap. On mine oil was
>certainly leaking down the exhaust valve stems and producing lots of blue
>smoke. Oil seals stopped it. But don't put oil seals on the exhaust valve
>stems if this is not the problem - they do need some oil. If putting seals
>on makes no difference, then take them off again.
>
>AND, you do not need to remove the head to do this. Use the string in the
>combustion chamber trick . Easy to do and much quicker!
>
>Quick way to check if the crankcase breather system is causing the smoke is
>to disconnect it at the manifold. put a bung in the manifold orifice and go
>for a drive. It will probably start to leak oil out of the crankshaft
>"seals" but if it stops blowing out oil smoke then you have found your
>problem.
>
>Guy
>----- Original Message -----
>From: "Brad Fornal" <toyman@digitex.net>
>Cc: "mg" <spridgets@autox.team.net>
>Sent: Monday, April 19, 2004 6:34 PM
>Subject: Re: Rebuilt motor
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