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Re: [GMCnet] Blackstone Labs and ZDDP oils [message #109521 is a reply to message #109503] Wed, 22 December 2010 22:53 Go to previous messageGo to previous message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma:
Senior Member
Fred, one of the GMC Cascaders just rebuilt his 455 and it was using oil
like crazy. He was using a Rockwell aluminum intake manifold with throttle
body FI. What he found was his intake manifold didn't have a good seal to
the valley, and it was injesting oil from that source. He removed the intake
& resealed it & his oil burning stopped. Engine ran very well and the plugs
looked good. Had us scratching our heads for a while before he found it.
Jim Hupy
Salem, Or
78 GMC Royale 403

On Wed, Dec 22, 2010 at 6:19 PM, Dennis S <dennisfsexton@aol.com> wrote:

>
> Fred,
> I can appreciate how frustrating this has been for you.
> If I remember you have also done compression tests and the results were
> guite good -- indicative of a strong engine. Really a puzzler.
>
> Dennis
>
>
> Dennis Sexton
> 73 GMC
> Germantown, TN
> USA
>
>
>
> -----Original Message-----
> From: fred veenschoten <fredntoni@cox.net>
> To: gmclist@temp.gmcnet.org
> Sent: Wed, Dec 22, 2010 5:42 pm
> Subject: Re: [GMCnet] Blackstone Labs and ZDDP oils
>
>
>
> Robert Mueller wrote on Wed, 22 December 2010 16:54
> Larry,
>
> I went to SAE 40 Royal Purple because I think it is an oil consumption
> issue
> related to engine speed and going to a single viscosity oil might help.
> This
> may be wishful thinking but I had a chat with the manager of the NAPA
> store
> where I bought the oil and the Royal Purple customer service engineer and
> the consensus that it would be worth a try to see what happens. If it
> didn't
> help it was an engine / ring / valve guide issue.
>
> The engine in Double Trouble was rebuilt by Ken Frey about 50,000 miles
> ago,
> had no sludge in the valve covers when I replaced the gaskets, no sludge
> in
> lifter valley just the "normal" burnt on crud when I swapped over to the
> aluminum manifold, and virtually none in the crankcase when I replaced the
> single drain oil pan with the dual drain.
>
> Regards,
> Rob M.
> USAussie - Downunder
>
> -----Original Message-----
> From: gmclist-bounces@temp.gmcnet.org
> [mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Larry
> Sent: Thursday, December 23, 2010 4:19 AM
> To: gmclist@temp.gmcnet.org
> Subject: Re: [GMCnet] Blackstone Labs and ZDDP oils
>
>
>
> you are aware that it takes some time for all the oil to run back to the
> pan
> so when you stop for gas your oil will always read low for about 20
> minutes.
>
> Fred V
> i've had consumption problems since buying my coach in '06. i first went to
> obil 1 oil with no change. since then i've changed the intake valve seals
> to
> he "positive seal" type, changed to the proper PCV valve, changed to the
> orrect valve covers, calibrated the dip stick, all with no change in oil
> onsumption. my engine was rebuilt 20K miles ago by the PO. i suspect a bad
> ebuild, probably rings or loose fitting pistons. i gave up and am looking
> for
> n engine to build and have ready when needed.
> --
> red V
> 77 Royale RB 455
> 'cola, Fl
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