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Old 01-25-2016, 01:17 PM   #255
davepl
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Join Date: Aug 2006
Location: Redmond, WA
Posts: 6,332
Re: Starting my engine build

Make sure you get the right "grade" of bolt. I assume cam bolts -could- be Grade 8, but do not know. They're marked on the top of the bolts, you can find a little chart online if that's news.

Setting the valves really isn't tricky but I think you need a mentor on that one, or lots of reading, or more posts!

Here's my nickel take on it:

- Get the cylinder in question to TDC by method of your choice
- Feel the up-down slack in the pushrod (there must be some, if not, back off nut until there is)
- Tighten the nut -just- until that up-down slack goes away - stop /right/ at the point where you've taken up all slack
- Tighten the nut 1/2 turn more (or 3/4 or 1/4, whatever the setting is, but 1/2 if in doubt)
- Move to next cylinder

Now I'll tell you two things I've observed watching my engine builder. The first is that he ignores my advice of looking for up-down slack. He feels the rotation of the pushrod. That's OK if you've been doing it 40 years, but a well-lubricated pushrod will still rotate long after the slack is taken up, even if the lifter is a little collapsed, so it's a bad way to do it. Any mistakes he made are 35 years ago though, but you don't want 5 years of mistakes :-) You want to know when there's no room left without collapsing the plunger, and slack tells you that.

The second thing is that he can work his way down the firing order... 1, then 8, then 4, then... actually he's got a shorter system so he doesn't have to walk around as much, I'll have to ask what the pattern is. But I bring each cylinder to TDC one after another, I'm not that fancy. Wastes a few rotations and a little walking I guess.

Others will no doubt have more detail and fill in some of the blanks.
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