LT1 Rocker adjustment?
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From: Isla Darwin
St. Jude Donor '03-'05-'06-'08, '14
GATORS Chomp OU 4 St. Jude '09
LT1 Rocker adjustment?
Question #
1: The book says there is a casting mark on the crank pulley so you can align it in the 12:00 pos. I can't find it using a flash light and mirror.
Is this on the face of the pulley or on the back?
2: The book says to tighten the rocker nut until all lash is removed, and then go one more turn. I did this and the valve compressed about a 1/4", and I'm pretty sure that is no good. Any advice here?
1: The book says there is a casting mark on the crank pulley so you can align it in the 12:00 pos. I can't find it using a flash light and mirror.
Is this on the face of the pulley or on the back?2: The book says to tighten the rocker nut until all lash is removed, and then go one more turn. I did this and the valve compressed about a 1/4", and I'm pretty sure that is no good. Any advice here?
Burning Brakes
Joined: Nov 2004
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From: Warren Ohio
1. The mark should be on the outside rim of the harmonic balancer....at least mine was on my '95. I had to scribe one on the new set when I installed my underdrive though.
2. You're not going to open the valve a 1/4" on a single turn. What procedure (step-by-step) are you using to determine zero lash?
2. You're not going to open the valve a 1/4" on a single turn. What procedure (step-by-step) are you using to determine zero lash?
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Joined: Dec 2003
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From: Isla Darwin
St. Jude Donor '03-'05-'06-'08, '14
GATORS Chomp OU 4 St. Jude '09
1: The mark wasn't there, or could not be found.
2: I got her done as perscribed by another method found on google that worked wonderful. It was my dumb azz that forgot hydraulic lifters have to be preloaded to cushion the mechanical action from the cam to the rocker. She idled 110% better after the adjustment and new plugs.
After adjustment, I ran her low RPM (with valve covers off) and still heard ticking coming from the rockers ( the tickinig seemed to be coming from all rockers). I tried to isolate by placing my finger on the rocker stud and sense the vibration, but all were pretty much the same. My guess is that the lifters are shot, or this is normal.
2: I got her done as perscribed by another method found on google that worked wonderful. It was my dumb azz that forgot hydraulic lifters have to be preloaded to cushion the mechanical action from the cam to the rocker. She idled 110% better after the adjustment and new plugs.
After adjustment, I ran her low RPM (with valve covers off) and still heard ticking coming from the rockers ( the tickinig seemed to be coming from all rockers).
I tried to isolate by placing my finger on the rocker stud and sense the vibration, but all were pretty much the same. My guess is that the lifters are shot, or this is normal.
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Team Owner
Joined: Dec 2003
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From: Isla Darwin
St. Jude Donor '03-'05-'06-'08, '14
GATORS Chomp OU 4 St. Jude '09
Originally Posted by 95PoloVert
1. The mark should be on the outside rim of the harmonic balancer....at least mine was on my '95. I had to scribe one on the new set when I installed my underdrive though.
2. You're not going to open the valve a 1/4" on a single turn. What procedure (step-by-step) are you using to determine zero lash?
2. You're not going to open the valve a 1/4" on a single turn. What procedure (step-by-step) are you using to determine zero lash?
Burning Brakes
Joined: Nov 2004
Posts: 1,057
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From: Warren Ohio
Some additional noise is normal, and varies depending on the rockers used. (I assume you also installed the LT4 Knock Module? If not, the additional noise will be interpreted as knock, and the computer will retard your timing to compensate.)
Sounds like you were doing this "cold" with the engine off....so if you weren't on the base circle of a given cam lobe when setting lash, you would get ticking as well. If you think this may be the case, go back and back off all the rockers, give the lifters a few minutes to pump up, then follow your procedure again, making sure that you are the on the base circle when doing a specific rocker.
Sounds like you were doing this "cold" with the engine off....so if you weren't on the base circle of a given cam lobe when setting lash, you would get ticking as well. If you think this may be the case, go back and back off all the rockers, give the lifters a few minutes to pump up, then follow your procedure again, making sure that you are the on the base circle when doing a specific rocker.
Safety Car
Joined: Apr 2004
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From: Lahaina Hi
