No power after engine swap...
#21
I will be checking the rocker adjustment. No one seems to be able to tell me if, while doing the engine on method of adjusting the rockers, I can loosen the rockers and tighten them til the poly lock just stops (instead of listening for when the clanking goes away, as I likely won't be able to hear it) and then add the preload.
#22
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I've not researched rollers much, but I thought you initially were supposed to use a feeler gauge *shrug* Why don't you like the 'rocker adjustment with the motor running' way? I mean, you say you won't be able to hear it, but it's worth a go right? Better than ripping everything off to look at the Opti
#23
I've not researched rollers much, but I thought you initially were supposed to use a feeler gauge *shrug* Why don't you like the 'rocker adjustment with the motor running' way? I mean, you say you won't be able to hear it, but it's worth a go right? Better than ripping everything off to look at the Opti
#24
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I will be checking the rocker adjustment. No one seems to be able to tell me if, while doing the engine on method of adjusting the rockers, I can loosen the rockers and tighten them til the poly lock just stops (instead of listening for when the clanking goes away, as I likely won't be able to hear it) and then add the preload.
"Step 7: Adjusting Intake Valves
We recommend you work with one cylinder at a time. Using the crankshaft dampener bolt in the snout of the crankshaft, turn the engine over by hand in the direction of its running rotation until the exhaust pushrod just begins to move upward to open the valve. Stop rotation. The lifter is now on the base circle of the cam and the intake valve is ready to be adjusted.
Hydraulic Lifter Cams: Tighten the polylock until all the slack is taken out of the rocker arm and pushrod. By lightly turning the pushrod with your fingers as you tighten the polylock, you will discover or feel a point at which there will be slight resistance. At this point, you have taken all the excess slack out of the pushrod. You are now at what we refer to as zero lash. Turn the polylock one-half turn more, and while holding it with a wrench tighten the set screw using a T-handle or allen wrench. This will give you the ideal pre-load of the rocker arm, pushrod, and lifter. Repeat this procedure for each cylinder and carefully adjust all intake valves.
Solid Lifter Cams: Consult cam spec card or cam manufacturer for correct lash specifications.
With the proper feeler gauge between the roller and valve stem, turn the polylock until a slight drag is felt on the feeler gauge. Hold the polylock with the wrench and then tighten the set screw using a T-handle or allen wrench. Repeat this procedure for each cylinder and carefully adjust all intake
valves.
Step 8: Adjusting Exhaust Valves
To adjust exhaust valves, turn the engine over until the intake pushrod moves all the way up.
Rotate past maximum lift, approximately one-half to two-thirds of the way back down. The lifter is now on the base circle and the exhaust valve can be adjusted.
Hydraulic Lifter Cams: Rotate the exhaust pushrod with your fingers and begin to tighten the exhaust polylock. When you feel the resistance on the pushrod, you are at zero lash. Rotate the polylock one-half turn more and then tighten the set screw. Go through the exhaust valves and repeat the procedure carefully. Now all of the valves are adjusted with the proper pre-load.
Solid Lifter Cams: Tighten the polylock, with the proper feeler gauge between the roller tip and valve, to the point at which there is a slight drag when moving the feeler gauge. Hold the polylock with the wrench and tighten set screw. Following this procedure carefully adjust all exhaust valves."
This is a cut and paste from the pdf. I was not able to attach the pdf, the software thought it was too large.
Last edited by koolaid_kid; 12-09-2008 at 08:12 PM.
#27
I swapped the distributor for the old one and no change. I pulled the valve covers and they were very off. I adjusted them with the engine running and I could feel the difference immediately. But just as I tried to get on it, bamm, I thing the opti blew. I just swapped the damn thing, now I have to do it again tomorrow.
#28
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I swapped the distributor for the old one and no change. I pulled the valve covers and they were very off. I adjusted them with the engine running and I could feel the difference immediately. But just as I tried to get on it, bamm, I thing the opti blew. I just swapped the damn thing, now I have to do it again tomorrow.
#31
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Get a dynotune. I got a tune from madz28....ran rich low, and LEAN up top. I was having the same issues you are, mine was a combination of valves adjusted wrong and a **** tune....
#32
I pulled off the opti and sure enough the rotor screws had backed out. I thread locked the rotor screws on the new opti and swapped in on. The car fired right up and ran well. I put the car in first, brought up the rpms, nailed it and the car got sideways, straightened it out, shifted into 2nd and the car got sideways again. So far so good. I still have to get another allen set screw, I lost one while adjusting the rockers, hopefully that rocker doesn't come way out of adjustment before I get a new one soon.
#33
I was never very lucky with the roll the push rod in your fingers and then another half turn method. I can always get the PR to turn if I try even after I bottom out the plunger in the lifter which can make you loose compression (holds the valve open and can damage the cam, lifters, bend PRs, etc. Not to mention it is easy to adjust them inconsistently). I have found one cylinder at a time and EO-IC. Here us a copy and paste that simplified my confusion. I have never had a problem adjusting valves since I found this.
---We like to start at the front of the driver-side engine bank with No. 1 cylinder. Contrary to what you might think, the first valve at the front of the left bank on the small-block Chevy is actually the exhaust valve. If you're not sure about whether a valve is an intake or an exhaust, the easiest way to tell is to line up the valve with either an intake or an exhaust port. If the engine has headers, the exhaust is easy to identify. Since our small-block only has two valves per cylinder, if the rocker is not lined up with an exhaust port, then it must be an intake port and vice versa.
To set the first pair of rockers, bump the engine over and watch the exhaust rocker arm. When it opens roughly a third of its total >> (exhaust opening--EO), stop and set the intake rocker arm. If you were to look at a cutaway of any four-stroke engine, when the exhaust valve just begins to open, the intake lobe would be on its base circle. That is when you want to set the intake.
To set the intake, back off the poly lock or adjustment nut until you know there is clearance. Then slowly tighten the nut until you can feel a slight resistance while twirling the pushrod between your fingers. This is zero clearance between the lifter, pushrod, rocker, and valve. If the engine is equipped with solid lifters, use a feeler gauge to establish the proper clearance between the rocker arm and the valve-stem tip. This is usually around 0.018 to 0.024 inch of clearance, but use the manufacturer's recommended lash. You want to establish a "feel" or slight tug on the feeler gauge and use that same amount of resistance for all 16 valves.
If you are setting preload on a hydraulic lifter-equipped engine, the process is a little different. Again, tighten the poly lock until all clearance is eliminated, and then tighten the adjuster another half-turn. This preloads the small piston in the bore of the lifter. Hydraulic oil pressure inside the lifter will maintain this preload throughout engine operation. Some manufacturers may require more preload, but a half-turn is a safe setting that most companies use. This half-turn also reduces the amount of distance the lifter's internal piston travels if the lifter "pumps up" due to an engine over-speed condition.
Now that we've set the intake lobe, we're ready to set the exhaust. Bump the engine over again and watch the intake lobe this time. Continue to bump the engine past max intake valve lift and stop when the intake is about halfway down on the closing side (IC--intake closing).
Now set the lash or preload on the exhaust valve for the same cylinder. Once you've done that, you're ready to move to the next cylinder. You don't have to do the engine sequentially. In fact, you could set lash by the firing order. However, we like to run down the cylinders from front to back to make sure we don't lose track of which rockers we've set. We end up bumping the engine over a few extra times this way, but it minimizes the chance of losing track of where you are and possibly missing a valve or two.----
After I adjust a hydraulic lifter valve I like to push down on the back of the rocker and make sure it moves (this is how you know that you haven't bottomed out the plunger and caused your self problems) If you can't move it at all back it off and try again. If I remember right they have about a .060 throw and you want them set in about half way meaning that between the valve stem and rocker tip you want about .030 when you press the back of the rocker down ( to check your plunge take the slack out of the rocker and then press the back of the rocker down, measure the distance between the rocker and valve tip when you adjust shoot for half the distance). If you want to get them nuts on consistent use a feeler gauge under the tip when you press the back down and make sure they all come out the same (this eliminates the the 1/4, 1/2, 3/4 turn controversy). If you have roller tip rockers you can still use the feeler gauge, just go in from the side so the tip doesn't "roll" onto the feeler gauge. I just use a $15 bump start remote starter switch from Schuck's to turn the motor over. It takes time, but I always know it is right and have had zero problems with my adjustments not to mention peace of mind instead of "I think I adjusted them correctly". Hope this helps.
---We like to start at the front of the driver-side engine bank with No. 1 cylinder. Contrary to what you might think, the first valve at the front of the left bank on the small-block Chevy is actually the exhaust valve. If you're not sure about whether a valve is an intake or an exhaust, the easiest way to tell is to line up the valve with either an intake or an exhaust port. If the engine has headers, the exhaust is easy to identify. Since our small-block only has two valves per cylinder, if the rocker is not lined up with an exhaust port, then it must be an intake port and vice versa.
To set the first pair of rockers, bump the engine over and watch the exhaust rocker arm. When it opens roughly a third of its total >> (exhaust opening--EO), stop and set the intake rocker arm. If you were to look at a cutaway of any four-stroke engine, when the exhaust valve just begins to open, the intake lobe would be on its base circle. That is when you want to set the intake.
To set the intake, back off the poly lock or adjustment nut until you know there is clearance. Then slowly tighten the nut until you can feel a slight resistance while twirling the pushrod between your fingers. This is zero clearance between the lifter, pushrod, rocker, and valve. If the engine is equipped with solid lifters, use a feeler gauge to establish the proper clearance between the rocker arm and the valve-stem tip. This is usually around 0.018 to 0.024 inch of clearance, but use the manufacturer's recommended lash. You want to establish a "feel" or slight tug on the feeler gauge and use that same amount of resistance for all 16 valves.
If you are setting preload on a hydraulic lifter-equipped engine, the process is a little different. Again, tighten the poly lock until all clearance is eliminated, and then tighten the adjuster another half-turn. This preloads the small piston in the bore of the lifter. Hydraulic oil pressure inside the lifter will maintain this preload throughout engine operation. Some manufacturers may require more preload, but a half-turn is a safe setting that most companies use. This half-turn also reduces the amount of distance the lifter's internal piston travels if the lifter "pumps up" due to an engine over-speed condition.
Now that we've set the intake lobe, we're ready to set the exhaust. Bump the engine over again and watch the intake lobe this time. Continue to bump the engine past max intake valve lift and stop when the intake is about halfway down on the closing side (IC--intake closing).
Now set the lash or preload on the exhaust valve for the same cylinder. Once you've done that, you're ready to move to the next cylinder. You don't have to do the engine sequentially. In fact, you could set lash by the firing order. However, we like to run down the cylinders from front to back to make sure we don't lose track of which rockers we've set. We end up bumping the engine over a few extra times this way, but it minimizes the chance of losing track of where you are and possibly missing a valve or two.----
After I adjust a hydraulic lifter valve I like to push down on the back of the rocker and make sure it moves (this is how you know that you haven't bottomed out the plunger and caused your self problems) If you can't move it at all back it off and try again. If I remember right they have about a .060 throw and you want them set in about half way meaning that between the valve stem and rocker tip you want about .030 when you press the back of the rocker down ( to check your plunge take the slack out of the rocker and then press the back of the rocker down, measure the distance between the rocker and valve tip when you adjust shoot for half the distance). If you want to get them nuts on consistent use a feeler gauge under the tip when you press the back down and make sure they all come out the same (this eliminates the the 1/4, 1/2, 3/4 turn controversy). If you have roller tip rockers you can still use the feeler gauge, just go in from the side so the tip doesn't "roll" onto the feeler gauge. I just use a $15 bump start remote starter switch from Schuck's to turn the motor over. It takes time, but I always know it is right and have had zero problems with my adjustments not to mention peace of mind instead of "I think I adjusted them correctly". Hope this helps.