[AJD] Antique-johndeere Digest, Vol 82, Issue 4

Michael mpmbd at yadtel.net
Tue Jan 10 13:34:37 PST 2012


And it is also true that propane has never had lead content. The tetraethyl 
lead was a low cost way to boost octane.

--------------------------------------------------
From: "David R. Gerber" <drgerber at fuse.net>
Sent: Tuesday, January 10, 2012 2:28 PM
To: "'Antique John Deere mailing list'" 
<antique-johndeere at lists.antique-tractor.com>
Subject: Re: [AJD] Antique-johndeere Digest, Vol 82, Issue 4

> My machine shop guru claims there is no need to put hardened valve seats 
> in
> any 2 cylinder engine, unless of course the valve seats need replaced
> anyway.  Reason:  the hardened valve seats are only needed in high rpm
> performance engines because the unleaded gas burns a little hotter, and 
> over
> time damages the valve seats.  Never going to be the case in the low rpm
> engines.  He has rebuilt several motors for me, and all continue to 
> perform
> without flaw, without hardened valve seats.  His recommendations are
> different with the four, six, and eight cylinder engines.
>
> Rev. Gerber
>
> -----Original Message-----
> From: antique-johndeere-bounces at lists.antique-tractor.com
> [mailto:antique-johndeere-bounces at lists.antique-tractor.com] On Behalf Of
> Michael
> Sent: Monday, January 09, 2012 5:29 PM
> To: Antique John Deere mailing list
> Subject: Re: [AJD] Antique-johndeere Digest, Vol 82, Issue 4
>
> I believe that the issue of lead and engine valves is a myth. Amoco ( now
> part of BP) premium gasoline ALWAYS has been unleaded. I easily recall the
> introduction of the Oldsmobile and Cadillac overhead valve V-8 engines in
> 1949. The largest and most powerful previous engine for Oldsmobile was
> straight-8 used from 1937 to 1948 inclusive. Not considered high 
> performance
>
> nor high compression. The V-8 was, relatively speaking, a powerhouse. 
> Owners
>
> seeking the best from the engine often used Amoco Premium- unleaded. Amoco
> even often pictured the Oldsmobile in their ads. I knew some owners who 
> used
>
> the Amoco Premium exclusively. I never ever heard of valve problems
> resulting and some of those cars were driven very hard.
 




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