How to tell if I overtightened the rocker arms ?
Cressidaadr
03-05-2009, 12:09 AM
I am putting my 98 Venture 3.4 engine back together after a bad headgasket. I pulled the heads and sent them out to get them checked out and had new valve stem seals installed.
I have it all sealed up and almost all back together but I am starting to worry that I may have overtightened the rocker arm bolts when I put the push rods back in place.
I was thinking I do not want to have open this engine up again for a loose rocker arm so I tightened them up more than I should have. I normally follow the specs but I was up to my elbows in oil and I remember something about another 30 degrees more and how in the heck am I suppose to get 30 degrees on that back head with all the wires and hoses back there in the way. So I just made sure they were all really tight - I would guess 45-50 ft. lbs.
I read that too loose will result in noise from the valves but too tight may cause poor idle or may not show any symptoms until you burn valves.
Are they any other symptoms I need to watch out for to know if I over did it? I am so tired of fighting with this darn engine maybe I am just over paranoid for now.
Since I haven't read of anyone really screwing up the rocker arms on this forum maybe the lifters have some range of adjustment ?
I have it all sealed up and almost all back together but I am starting to worry that I may have overtightened the rocker arm bolts when I put the push rods back in place.
I was thinking I do not want to have open this engine up again for a loose rocker arm so I tightened them up more than I should have. I normally follow the specs but I was up to my elbows in oil and I remember something about another 30 degrees more and how in the heck am I suppose to get 30 degrees on that back head with all the wires and hoses back there in the way. So I just made sure they were all really tight - I would guess 45-50 ft. lbs.
I read that too loose will result in noise from the valves but too tight may cause poor idle or may not show any symptoms until you burn valves.
Are they any other symptoms I need to watch out for to know if I over did it? I am so tired of fighting with this darn engine maybe I am just over paranoid for now.
Since I haven't read of anyone really screwing up the rocker arms on this forum maybe the lifters have some range of adjustment ?
merc81
03-05-2009, 07:38 AM
Maybe some confusion as to how the rocker arms work in this engine? It used to be that when doing a valve job, you had to reinstall the rocker arm nuts and adjust valve lash by adjusting the torque on the rocker arm nuts.
This engine is not adjustable in that way. The rocker arms are roller rockers (needle bearings in the rockers) and you can't overtighten them in any functional way. I mean you can have any torque on the rocker arm bolts and the valve will work the same regardless.
It may be that the bolt snaps because its too tight, or it falls off because its too loose, but those are extreme cases and I doubt you did either of those mistakes. Regardless of the torque on the bolt, the valve and rocker arm are still going to perform the same.
The spec is 14 lb ft + 30 degrees.
I imagine you would have done a reasonable job of getting the bolts all close to the same value and that would be reasonably close to the correct value. There is no problem with slight imperfections as there was with the old GM engines with valve lash adjustments.
This engine is not adjustable in that way. The rocker arms are roller rockers (needle bearings in the rockers) and you can't overtighten them in any functional way. I mean you can have any torque on the rocker arm bolts and the valve will work the same regardless.
It may be that the bolt snaps because its too tight, or it falls off because its too loose, but those are extreme cases and I doubt you did either of those mistakes. Regardless of the torque on the bolt, the valve and rocker arm are still going to perform the same.
The spec is 14 lb ft + 30 degrees.
I imagine you would have done a reasonable job of getting the bolts all close to the same value and that would be reasonably close to the correct value. There is no problem with slight imperfections as there was with the old GM engines with valve lash adjustments.
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