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Re: is this engine blown?

To: "Daniel Neuman" <neuman@RadOnc17.UCSF.Edu>,
Subject: Re: is this engine blown?
From: "Mark Sedlack" <msedlack@neo.rr.com>
Date: Tue, 30 Dec 2003 23:07:13 -0500
Daniel,
It sounds like your pump's pressure circuit went south.  In a SBC, the pump
is driven by a tang on the end of the distributor shaft, and since the car
still runs, that would rule out a shattered distributor drive gear.  Pull
your HEI and inspect the bottom of the distributor shaft for damage to the
tang on the end.  If that's OK, then its the pump.

You'll have to drop the pan to get at the pump.  If you can get the pan off
without pulling the motor (sometimes you can unbolt the mounts and jack the
block up slightly for clearance) , you can can replace the pump, and pop the
main caps ( one at a time ) to inspect the crank and bearings for damage.
Hopefully the noise you heard was just the rockers clattering from from lack
of pressure in the hydraulic lifters.  Small blocks have pretty generous
bearing clearances and since they don't normally operate at high revs, can
survive a period of low oil pressure better that smaller displacement higher
revving engines.
A replacement pump, like most SBC parts, is a cheap replacement - you can
get a good quality Melling for about $20.
Mark Sedlack
ZROC
Cuyahoga Falls OH
66 1600 http://www.mildevco.net/chevypowereddatsuns/
77 280Z http://www.mildevco.net/chevypowereddatsuns/

----- Original Message ----- 
From: "Daniel Neuman" <neuman@RadOnc17.UCSF.Edu>
To: <datsun-roadsters@autox.team.net>
Sent: Tuesday, December 30, 2003 5:04 PM
Subject: is this engine blown?


> Hello All,
> I need y'alls collective engine wisdom.  On xmass day we were
> cruising to the big family gathering in Irene's Jag- the one with the
> 350/350 combo.  Something must of happened along the way and it started to
> overheat...I watched the oil pressure go from 40-20-10-ish as I was
> attempting to make it to an off ramp.
> Had the car towed home and checked it out over the weekend.  The oil
> was really really foul-burnt nasty smelling.  I changed the oil and the
> coolant and the plugs and started the car up.  It started up fine and at
> idle it sounded a little noisy like a rocker arm was not adjusted
correctly.
> When I rev'd it up above idle it starts to make a horrible racket and
there
> is no oil pressure showing on the gauge.  If I had to guess I would say
the
> racket is coming from the lower part of the engine.  I popped the valve
> covers off and the rocker arms and pushrods look okay.
> What do you guys think is wrong?  Did I destroy the crankshaft
> bearings?  The engine is not leaking oil why do I not have any oil
pressure?
> Thanks,
> Daniel Neuman
> Oakland CA
> 69 2000 (which still runs great)





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