valve adjustments

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mattbaker302
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Joined: Fri Sep 06, 2019 2:54 pm

valve adjustments

Post by mattbaker302 »

hey guys so I'm a new member was told about this site by a guy who sold me a timing cover. well here's what's going on
I built my 302 into a 306 after I installed the cam and lifters and rocker arms, I did the 0-lash then 1/2 turn for "best results " but when I started her she runs really rough and will hardly idle(the motor will rock).
so I backed them all off and I'm trying to adjust them while its running and I get her ticking then turn until it stops and it sounds okay until I do the other half turn to set it, then it starts idle rough and tries to die....
I don't know what to do next
Mach428
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Re: valve adjustments

Post by Mach428 »

How long does it run rough? You should turn 1/4 turn each time and wait until the idle smoothed out, then proceed.
RottenAppleRed
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Location: Anderson, Indiana

Re: valve adjustments

Post by RottenAppleRed »

I have never went past 1/4 turn after zero lash on a small block Ford (including Cleveland) ever. I adjust the rockers when the opposing valve is open...so basically, if the #1 intake valve is open, adjust the #1 exhaust valve...and so on. The trick is to wiggle the pushrod up and down as you slowly tighten the rocker nut to zero lash. Spinning the pushrod can give a false zero, where the lifter is actually compressed a bit. Remember to make a line on the rocker with a sharpie, after you adjust it.

Another thing to check is the cam card for the correct firing order and route the plug wires accordingly.
mattbaker302
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Re: valve adjustments

Post by mattbaker302 »

well the 1/4th turn seemed to be the sweet spot, runs like a champ(ish) have 1 or 2 tappers that need some adjusting but other than that it's all good.
hard to tell the tapping of lifters apart from the exhaust leak:) that's my fault, thanks to 16-year-old me buying the cheapest eBay headers that were shiny. but for right now its good enough for the girls I go with. Thanks for the replies!
RottenAppleRed
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Location: Anderson, Indiana

Re: valve adjustments

Post by RottenAppleRed »

Here’s a tip for the headers...lose the gaskets. Get some high temp sealant, put a thin bead on the header ports and install the headers. Let them cure before firing the engine. I know this method is unorthodox, but it works every time.
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