Marc,
Thanks. Another myth that was wrong,
Mike
----- Original Message -----
From: Marc Sayer <msayer1@concentric.net>
To: datsunmike <datsunmike@nyc.rr.com>
Cc: <CalSpeed@aol.com>; <datsun-roadsters@autox.team.net>
Sent: Wednesday, October 04, 2000 10:42 PM
Subject: Re: Starter / Compression
> This concept seems to have more lives than a cheap politician. I don't
> know where or how it got started for sure but I think it has to do with
> some of the older cars and trucks that used heavy gear oils in the
> trannys or something. Anyway it is dead wrong. No better way to load the
> engine than to depress the clutch. The only exception would be cold
> weather starts in cars with very heavy gear oil in the trans (a sure way
> to ruin the trans and there is no need with today's lubricants). In that
> case the fluid drag and friction losses in the tranny might create more
> drag on the crank than depressing the clutch would.
>
> When you depress the clutch you are loading the thrust washers with the
> full load of the clutch (0n the comp clutch that's 650 kg or about 1400
> lb.) before there is any oil on the thrust faces (and before the crank
> has developed any gyro effect but that's a whole other thing and
> opinions differ on that quite a bit so lets just stick with lubrication
> factor). It is absolutely the worst thing you can do to your crank and
> thrust washers. Over the years I got so as I could identify clutch
> riders by the wear in the cranks and thrust washers. When you ride the
> clutch at idle you are loading the thrusts surfaces the same way as when
> starting but at least oil is being supplied to them. Do it before you
> crank the engine and you are pushing bare metal to bare metal and then
> spinning the one against the other. Yikes!
>
> Not only does it load the engine and make starting harder, it wears out
> the crank and thrust washers much faster.
>
> > BTW, do you start it with the clutch depressed? I read that it is a good
> > idea and makes it easier to crank over.
>
>
> --
> Marc Sayer
> Editor/Publisher
> Z Car & Classic Datsun Magazine
> http://zcarmag.com
> Voice 541-726-6001
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