Yeah, the lobes aren't exactly at 10 and 2, that's just a convenient way to
think of it when adjusting the valves. But if you had serious resistance when
turning the engine over by hand, then I'd suspect there has been valve-to-piston
contact. It doesn't sound like the shop that assembled it knew what they were
doing with the timing chains. If it was my engine, I'd tear it down and start
over. But if you do that, you won't have any recourse with the shop.
Gordon Glasgow
Renton, WA
> -----Original Message-----
> From: owner-datsun-roadsters@autox.team.net
> [mailto:owner-datsun-roadsters@autox.team.net]On Behalf Of Allen
> Blackmon
> Sent: Tuesday, November 26, 2002 2:04 PM
> To: datsun-roadsters@autox.team.net
> Subject: B cam lobes and timing
>
>
> To List,
>
> What's this? Another timing question from that moron? Okay, here's the
> latest. I suspect the shop that put my engine together screwed up. When
> the engine is at TDC, what are the positions of the cam lobes for #1 with a
> B cam? Should the cam gear top screw be at 12? If so, then my lobes are
> not at 10 and 2 (more like 11 and 2:30). Or should the cam lobes be
> equidistantly apart from the "noon" position and pay no attention that the
> cam screw is not at noon?
>
> If you've read my prior posts, you are aware of my problems starting this
> car. As it is now, I can only get it to run when the ignition is set at
> about 35 - 40 degrees BTDC. Which if my cam gear is off one tooth,
> corresponds to about 20 BTDC. Also, my car backfires and I see a bit of
> exhaust coming out of carbs, as well as fule coming back out of both carbs.
> In this condition it does not run as intended. I've checked timing and it
> is firing 1-3-4-2 counter clockwise as required. Also have Gary's EI, so
> that is not a problem.
>
> Further, if I turn the crank by hand (w/o plugs) it is very hard at a few
> points, so hard that I need a bit of help to get it to move.
>
> In looking in the cylinders, I can see in #1 a slight mark that would
> correspond to a valve hitting it. So it looks like the shop set it up
> wrong.
>
> I have moved the cam gear over one tooth. Turning the engine by hand is
> easier than the way it was set up by the shop. I have not yet turned the
> engine over by teh starter as I would like List advice on my issues,
> including cam lobe positions. TIA
>
> Allen
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