Gt40p loose rocker?

[PeteK70]

I have a 2000 explorer 5.0 engine in a 76 bronco. I was noticing a ticking sound, mainly at idle so ended up removing valve covers and was wondering if this is normal for the rocker to be loose? I can move only one a little but enough to make a noise. Any help would be appreciated. Here is a link to the video:

 

[DirtDonk]

Do you know for a fact that this is the one that is making the noise? Did you verify that with a stethoscope or other device to pinpoint sound?

Reason I ask is because from here at least, it’s hard to tell if that one is actually loose. It’s very common to be able to move a rocker arm around side to side and easily spin the push rod when the valve is closed. There is a point after which they do make noise. But it’s hard to tell from the video if that’s the case here.

 

[Germd]

Agree with dirtdonk. Suggest using a stethoscope to listen on the valve cover surface over each set of rockers with the engine running. If you don’t have access to a stethoscope, you can even use a long screwdriver or long ratchet extension & touch one end to the valve cover & the other end to your ear. Just be extra careful with the second method !

 

[lars]

P heads use pedestal mount rockers. The mounting bolt should be tight (there is a torque spec but I don't remember it offhand). In any case, DirtDonk and Germd are right. If the valve is closed the rocker arm can move and the pushrod can be spun easily. If there is noise coming from the valve, either the valve is bad or the lifter is collapsed.

 

[jamesroney]

Pedestal rockers are tricky...because you have to be careful how much you back them off, and they limit how tight you can go.
I'm not a big fan of stethoscopes, and I have little patience for playing "where's Waldo" with lifter noise.

So I just fire it up, and back off the pedestal mounting bolt about a turn. They will go "clackety clack" and then the noise goes away when you tighten the bolt down to it's positive stop. When you find the one that doesn't make more noise when you loosen it...that's the bad one.
If it's really loose, you can just put your hand on it to find the one that's noisy.

It turns out that Ford did not build the engine with a loose rocker, or a short pushrod / valve stem. So once you figure out which one is loose, you have identified which roller lifter has collapsed and needs to be replaced. I suppose that might be useful information if you plan to replace just one. I have NEVER pulled an intake just to replace a single lifter. I always replace the set. So then you have to wonder why you are bothering to do the diagnosis. But you asked a specific question, and so you are getting specific answers.

The answer to the question that you didn't ask is "no." It is not normal for a rocker to be loose. Your video does not help to determine whether the rocker is loose or not. In either case, you don't have a loose rocker. You have a collapsed lifter. The collapsed lifter presents itself as a loose rocker. If this was a Small Block Chevy...(or an adjustable stud mount SBF) then you could tighten the lifter, stop the noise, and burn the valve.

So the bottom line is that is wasn't ticking for 25 years, now it ticks, and it cannot be fixed by tightening anything.

 

[Timmy390]

Yes.......I had one on my junk yard GT40P heads off a 2001 Mountaineer. Only one.......to verify it I went to the salvage yard and grabbed a factory valve cover. Once home I cut the top out of it so I could see the rockers and not get oil all over.

Worked great......you can also verify proper oiling with the "windowed" valve cover.

Tim

 

[PeteK70]

I appreciate all the comments. I put this engine in a couple years ago and have had the ticking sound since then. Not right after startup but after about a minute or so it starts ticking. It has drove fine and never had any issues besides the ticking. I have tried the stethoscope and dowel rod to try and find where it comes from but have never been able to identify exactly where. I got some different valve covers hoping maybe it was barely tapping the valve cover so had it opened up and was just feeling around for anything strange. If a lifter was bad, would I be able to drive very far before the engine self destructed? It has been driving mountain passes with no issues other than the annoying ticking sound. I guess I will put the new valve covers on and see if that changes anything, then try the window valve cover method.