H/C/I 331, rant

Are the valves adjusted properly? Once it warmed up it could be hanging them open.

Stud mount I assume?

Zero lash is the point when you feel resistance when turning the pushrod. As soon as you feel resistance to rotate, tighten the rocker nut 1/2 turn and lock.

If you are turning the pushrod and tightening until you can not longer turn the pushrod by hand, then your valves are adjusted too tight and hanging open.

Do a search. There are plenty of threads that discuss this topic in detail.

FROM CRANE CAMS

Adjusting Hydraulic Lifters for Proper Preload
In order to adjust the preload the lifter must be properly located on the base circle or “Heel” of the lobe. At this position the valve is closed and there is no lift taking place. You will need to watch the movement of the valves to determine which lifter is properly positioned for adjusting.
1. Remove the valve covers, and pick a cylinder you are going to set the preload on.
2. Hand rotate the engine in its normal direction of rotation and watch the exhaust valve on that particular cylinder. When the exhaust valve begins to open, stop and adjust that cylinder’s intake rocker arm. (Why? Because when the exhaust valve is just beginning to open, the intake lifter will be on the base circle of the lobe, the correct position for adjusting the intake.)
3. Back off the intake rocker arm adjuster and remove any tension from the pushrod. Wait a minute or two for that hydraulic lifter to return to a neutral position. The spring inside the lifter will move the pushrod seat up against the retaining lock if you give it time to do so. (If you are installing brand new lifters they will be in the neutral position when they come in the box.)
4. Now spin the intake pushrod with your fingers while tightening down the rocker arm. When you feel a slight resistance to the turning of the pushrod, you are at “Zero Lash”. Turn the adjusting nut down one half to one full turn from that point. Lock the adjuster into position. The intake is now adjusted properly.
5. Continue to hand turn the engine, watching that same intake. It will go to full open and then begin to close. When it is almost closed, stop and adjust the exhaust rocker arm on that particular cylinder. (Again, when we see the intake almost closed, we are sure that exhaust lifter is on the base circle of the lobe.) Loosen the exhaust rocker arm and follow the same procedure described before in steps 3 and 4 to adjust this rocker arm.
6. Both valves on this cylinder are now adjusted, and you can move on to your next cylinder and follow the same procedure again.
Do Hydraulic Lifters Need to be Primed with Oil?
Many people mistakenly believe that hydraulic lifters must be soaked in oil overnight and be hand pumped up with a pushrod before installing into a new engine, however this is not necessary. In fact, this could cause the lifter to act as a “solid” and prevent obtaining proper preload. What is very necessary is the priming of the entire engine’s oil system before starting up a new engine for the first time. This is done by turning the oil pump with a drill motor to force oil throughout the entire engine. Crane Cams offers oil pump primers for Chevrolet and Ford engines

It's just easier to find zero lash while turning and feeling resistance then trying to feel up and down movement. Plus you have to think of the minor turn it takes to use one or the other method.


To the poster, once it starts missing, shut it down and do a compression test quickly. I bet you will find some are hanging open. You could try and readjust the valves, maybe some lifters were bled down and you didn't feel the right preload.

Did you check proper pushrod lenth?

Plug wires aren't layin on the headers right? Any codes? Mine had a similar problem and it was the wire to the injector, a running engine test would tell tell you if that was something with it.

I'm voting for something with the wires or ignition related.....

90five0oh said:

see when we first tried to crank it they were too tight. so we tore it back down and loosened em up. we went 1/2 turn past the point when the pushrod stops turning, at first it was 3/4 past

Click to expand...

thats prolly your problem.your only supposed to turn the nut (with fingertips) until u feel SLIGHT resistance with the pushrod. goodness, you probably have those suckers way too tight

there should be one that says vids too

It feels good being right

Good job. Glad it's fixed!!!

90five0oh said:

i cant get my computer to upload the video i made. any suggestions?

Click to expand...

make it work

90five0oh said:

i cant get my computer to upload the video i made. any suggestions?

Click to expand...

What type of camera is it. Does it use a DVR tape? disc? or memory card?