pulling out rocker arm posts and bending pushrods!???
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Joined: May 2003
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From: Georgia
pulling out rocker arm posts and bending pushrods!???
When we pulled the valve cover off we noticed that some of the springs were sticking which caused some bent pushrods. We replaced the pushrods and then noticed that the post for the rocker arms on the cylinders that didn't work were quite a bit higher than the other ones.
Does anyone have any suggestions about what to do?
What would cause this?
How to get them back down to the right height?
Any help would be greatly appreciated. Thanks
Greg
Does anyone have any suggestions about what to do?
What would cause this?
How to get them back down to the right height?
Any help would be greatly appreciated. Thanks
Greg
Elder User
Joined: Aug 2002
Posts: 662
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From: CA
pulling out rocker arm posts and bending pushrods!???
A couple of thought come to mind:
Are you running racing valve springs and/or a high lift cam? If so, check the fully compressed spring heigth and the installed heigth. Check the difference with the lift specs of the cam. Your springs might be fully compressing before the cam lobe is fully up, in which case something has to give. A pushrod will bend, or the rocker studs will slowly pull up. You might have springs that are just too darn strong, or a cam that lifts too high.
If that's not the case, check the lifters. If there's dirt in them, they might pump up and then stay in the pumped up condition, which can cause these problems, particularly if your rockers are torqued down too far.
It's even possible that, prehaps due to an oiling problem, some of your valves are sticking in a closed position. That will bend pushrods and pop rocker studs pretty quickly.
These might not cover your problem, but I've seen them all. I've even seen this from valves hitting piston tops (too much cam or no relief in pistons).
Are you running racing valve springs and/or a high lift cam? If so, check the fully compressed spring heigth and the installed heigth. Check the difference with the lift specs of the cam. Your springs might be fully compressing before the cam lobe is fully up, in which case something has to give. A pushrod will bend, or the rocker studs will slowly pull up. You might have springs that are just too darn strong, or a cam that lifts too high.
If that's not the case, check the lifters. If there's dirt in them, they might pump up and then stay in the pumped up condition, which can cause these problems, particularly if your rockers are torqued down too far.
It's even possible that, prehaps due to an oiling problem, some of your valves are sticking in a closed position. That will bend pushrods and pop rocker studs pretty quickly.
These might not cover your problem, but I've seen them all. I've even seen this from valves hitting piston tops (too much cam or no relief in pistons).
Elder User
Joined: Dec 2002
Posts: 925
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From: Quaker Hill ,CT U.S.A.
pulling out rocker arm posts and bending pushrods!???
I have seen a '73 460 bend push rods due to it sitting . The valves rusted/stuck to the valve guides and thus bent all the push rods .
What engine are you talking about ? Sounds like a 360 or a 390 if so check out this link:https://www.ford-trucks.com/articles/pushrods.php
What engine are you talking about ? Sounds like a 360 or a 390 if so check out this link:https://www.ford-trucks.com/articles/pushrods.php
