Finding TDC for piston #1
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Racer
Joined: Sep 2012
Posts: 369
Likes: 59
From: North Georgia
Finding TDC for piston #1
In order to "properly" torque the rocker bolts I first have to find TDC for piston #1. Can I do that by pumping up another cylinder with air? And what # cylinder would that be? When I pumped up the cylinders with air to swap out valve springs, it sounded like the whole engine turned over, but I might be wrong on that.
Spaggs
Spaggs
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2020 Corvette of the Year Finalist (performance mods)
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stock rockers?... if so don't waste your time setting it to tdc, just go down the line and tighten them
Drifting
Joined: Jul 2015
Posts: 1,844
Likes: 375
From: San Jose, CA
No. You want to rotate the crank itself. There are various ways of doing this, the simplest is to stick a rod through the spark plug hole to feel the piston top, get it to near tdc, and fine-tune by hand till you're satisfied. A better way includes using a gauge to measure the height of said rod, or otherwise measure the height of the piston, and move to (eg) 60 thou before tdc and 60 thou past tdc and split the difference.
Safety Car
Joined: Jun 2017
Posts: 4,786
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From: North Georgia, USA
In order to "properly" torque the rocker bolts I first have to find TDC for piston #1. Can I do that by pumping up another cylinder with air? And what # cylinder would that be? When I pumped up the cylinders with air to swap out valve springs, it sounded like the whole engine turned over, but I might be wrong on that.
Spaggs
Spaggs
