probably either cam bearings or rocker arm/shaft wear or a combination of both.
jerry wall
BN6
Paul Baker wrote:
>
> After 3 years racing and 12,000 competitive miles (not all by me), I thought I
> would treat my BJ8 to an engine rebuild. Prior to the rebuild, the engine
>used a
> little oil and smoked a bit on overrun, but the oil pressure was 4 bar (60
>psi)
> cold tickover and 2 bar (30 psi) when hot and on tickover. I have always used
> Castrol RS 10-60 (fully synthetic). During the rebuild the main and big end
> bearings were replaced although there was very little wear to the old set, the
> piston rings were changed, the oil pump was replaced for a new D. Welch h/c
>pump
> (due to excessive wear in the gears of the std BJ8 pump) and the cam, valve
> springs, seals and bucket followers were replaced (valve guides were fine).
> Overall the engine was in very good condition.
>
> I have since run in the engine using Castrol No 2 running-in oil for the first
> 300 miles and replaced it with a 10-40 mineral oil for the next 500 or as many
> miles as I can get on it before the next race season starts, when it will be
> replaced with Castrol RS 10-60.
>
> The problem is that the oil pressure since the rebuild and is now 3 bar (45
>psi)
> on cold tick over and 1.8 bar (26 psi) when hot. I can't see that this is
>going
> to improve greatly when I replace the 10-40 with the 10-60. My engine
>rebuilder
> is somewhat baffled by this outcome. We plan to check the oil pressure relief
> valve but this was not touched during the rebuild but what else could be
>causing
> this problem?
>
> As always, any suggestions greatly appreciated.
>
> Paul
>
> 66 BJ8 works rep
> 67 BJ8
>
>
>
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