74 302 valve adjustment
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From: maui.HI
74 302 valve adjustment
I tried posting this in the engine forum but got no response so I'd like to try it here.<HR style="COLOR: #666666" SIZE=1>
It's been over ten years since I did this and I don't remember how its done. I've got a 74 early bronco with a 302. Its got the stock heads with stock rockers. I wanted to check valve clearence. My manual says to bleed down the lifters but I can't remember how to do it. Can someone give me a valve adjustment refresher? thanks
It's been over ten years since I did this and I don't remember how its done. I've got a 74 early bronco with a 302. Its got the stock heads with stock rockers. I wanted to check valve clearence. My manual says to bleed down the lifters but I can't remember how to do it. Can someone give me a valve adjustment refresher? thanks
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From: Denver, CO
Is it smoking? Mine does and I keep saying I am going to do something about it, but I keep holding out waiting for the deal on a 5.0 EFI to come along. Wish I could help, but if I were to fix mine, I would be relying on my mechanic cousin.
J.D.
J.D.
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From: Southern Oregon USA
According to my manual, a '74 should have positive stop rocker studs.
The only way the valves can be adjusted is by using different length pushrods.
To determine if you need different length pushrods: Turn engine over to TDC compression on the cyl you are checking. Count the number of rocker arm nut turns it takes to bottom each rocker arm pivot on its stud shoulder from the point all slack is taken out of the pushrod and rocker arm, but before any lifter plunger moves. Wiggle the rocker arm and rotate the pushrod to check for slack. Look at the lifter to see if the plunger has moved. Run the nut down while keeping track of the turns. When the pivot bottoms or the turning torque increases, stop turning. The specs for the 302 are between 3/4 and 1 3/4 turns. Fewer turns will mean that a shorter pushrod is needed, more turns call for a longer pushrod. If it is in spec, torque to 18 ft/ lbs.
If your engine is in good running condition and the valve seats are still in good shape and not beat into the head, you shouldn't need to adjust them.
Jason
The only way the valves can be adjusted is by using different length pushrods.
To determine if you need different length pushrods: Turn engine over to TDC compression on the cyl you are checking. Count the number of rocker arm nut turns it takes to bottom each rocker arm pivot on its stud shoulder from the point all slack is taken out of the pushrod and rocker arm, but before any lifter plunger moves. Wiggle the rocker arm and rotate the pushrod to check for slack. Look at the lifter to see if the plunger has moved. Run the nut down while keeping track of the turns. When the pivot bottoms or the turning torque increases, stop turning. The specs for the 302 are between 3/4 and 1 3/4 turns. Fewer turns will mean that a shorter pushrod is needed, more turns call for a longer pushrod. If it is in spec, torque to 18 ft/ lbs.
If your engine is in good running condition and the valve seats are still in good shape and not beat into the head, you shouldn't need to adjust them.
Jason
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