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Misfires on 4,5,8. Iím going to document what I try.

 
  #16  
Old 04-12-2019, 08:47 AM
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Originally Posted by Krewat View Post
They're not "rockers" they are "followers".

4.6L head, but same thing as the v10:
Thanks for posting the photo. Iíve only ever had cars with OHC and the cams on those depressed lifters that actuated the valves. This helps.
 
  #17  
Old 04-12-2019, 08:48 AM
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Originally Posted by Im50fast View Post
That one injector is scary-bad. No way will that cylinder run properly. I wouldnít run that injector until having it professionally cleaned and flow tested. (Might as well do the others while youíre at it)

The question is why/how it got that bad. You should use your scope to look into the intake passages- you have to find the cause of sludge on the injector tip.

Im subscribing to this thread - I want to see how this turns out.
good idea to stick the scope down the intake. Iíll do that!
 
  #18  
Old 04-12-2019, 09:12 AM
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Ah followers, right. Bad habit to use old terms for referencing things. My fault.
 
  #19  
Old 04-12-2019, 10:15 AM
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Originally Posted by johnfist View Post
Ah followers, right. Bad habit to use old terms for referencing things. My fault.
I can totally see why youíd call those rockers.
 
  #20  
Old 04-13-2019, 06:08 AM
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Originally Posted by johnfist View Post
Ah followers, right. Bad habit to use old terms for referencing things. My fault.
Originally Posted by wbubble View Post
I can totally see why youíd call those rockers.
Moot point perhaps but a rocker would be a part that changes the direction of something, in this case the lift of an in-block camshaft pushing up on a lift rod and in turn pushing downward on a sprung valve.

The follower simply following the camshaft lobe without changing direction of the cam lift.

Not sure that's the true technical explanation but it works for me, at least understanding the different terms.
 
  #21  
Old 04-14-2019, 01:49 PM
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Cam looks good.

Looking under the cam cover while the coils and TB are off. Cylinders 5 and 4 cam and followers appear to be smooth and operational to my eye and touch.

To to be honest, other than scratched metal or broken followers Iím not sure what else to look for here. It looks good to me.


Cylinder 4.


Cylinder 5

Another view
 
  #22  
Old 04-14-2019, 01:51 PM
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A theory.

Iím starting to wonder if the cylinder 4 injector went bad, which caused the plug to foul badly and the fact that 4 is dead made the ECU also register that 5 had a misfire too.
 
  #23  
Old 04-14-2019, 02:56 PM
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Iím not an expert but Iíd say your cam lobe wear looks questionable. I just had mine apart and none of them had that pattern like yours.
The followers can go bad to where they look ok but in actuality the rollers donít roll.
By my theory yours would be in the early stage of failure though. Which probably wouldnít couldnít make it run bad. Probably would just cause some noise.
I also noticed that a few of my 335,000-mile lifters were bad. Maybe thatís your root cause.

Keep us posted.
 
  #24  
Old 04-14-2019, 03:35 PM
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Originally Posted by Im50fast View Post
Iím not an expert but Iíd say your cam lobe wear looks questionable. I just had mine apart and none of them had that pattern like yours.

Keep us posted.
Perhaps itís just the very direct light for my photos. Running my fingers over them, gloves and bare skinned, I couldnít feel anything uneven.

Iím proceeding with optimism.
 
  #25  
Old 04-14-2019, 05:13 PM
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Originally Posted by wbubble View Post
Perhaps itís just the very direct light for my photos. Running my fingers over them, gloves and bare skinned, I couldnít feel anything uneven.

Iím proceeding with optimism.
i respect your optimism. Iíd say to have a close look at all the others and compare. Not sure if your pics show other cylindersí cam lobes
 
  #26  
Old 04-14-2019, 06:56 PM
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Originally Posted by Im50fast View Post
i respect your optimism. Iíd say to have a close look at all the others and compare. Not sure if your pics show other cylindersí cam lobes
I think they look good.

 
  #27  
Old 04-15-2019, 07:38 AM
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My opinion is while you have it open, get the tool for removing them, and pull the questionable ones out and feel if the bearing is rough or sticky. It'd be unfortunate to have to open her back up in 10-20k miles and see big problems.
 
  #28  
Old 04-16-2019, 06:06 AM
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Originally Posted by johnfist View Post
My opinion is while you have it open, get the tool for removing them, and pull the questionable ones out and feel if the bearing is rough or sticky. It'd be unfortunate to have to open her back up in 10-20k miles and see big problems.
i agree fully with this guy. Those rollers could be bad in such a way that they look ok as they are. But if you take them out and they be wobbly or something.

Youre already in this deep; might as well keep digging.
 
  #29  
Old 04-16-2019, 09:13 AM
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Originally Posted by Im50fast View Post

Youre already in this deep; might as well keep digging.
If I knew what I was looking for, I would agree, but I need to stop somewhere and nothing on the cam or followers indicates what caused my misfire. I have a good friend whose pal is a ford tech. Iím gonna have him take a peek and advise if Iím safe putting her back together to test the injector theory.

Im very hesitant to ďjust keep digging.Ē Next thing you know Iíll have the head off and will have spend a bunch of money on replacement parts that were working fine but I felt I had to replace just because I was in there. Not to mention the time Iíd rather spend with my wife and kids.

Feels like Iím between a rock and a hard place. Iíll report back if Iím able to get the tech out to put his hands on the cam.

Valve cover gaskets arrive today.
 
  #30  
Old 04-16-2019, 09:08 PM
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Originally Posted by wbubble View Post
If I knew what I was looking for, I would agree, but I need to stop somewhere and nothing on the cam or followers indicates what caused my misfire. I have a good friend whose pal is a ford tech. Iím gonna have him take a peek and advise if Iím safe putting her back together to test the injector theory.

Im very hesitant to ďjust keep digging.Ē Next thing you know Iíll have the head off and will have spend a bunch of money on replacement parts that were working fine but I felt I had to replace just because I was in there. Not to mention the time Iíd rather spend with my wife and kids.

Feels like Iím between a rock and a hard place. Iíll report back if Iím able to get the tech out to put his hands on the cam.

Valve cover gaskets arrive today.
i donít know how to multi-quote so I bolded in your message.

I completely agree. I started with #5 getting tiny amounts of coolant, which lead to the head removal and replacement.

ďMight as wellĒ get the replacement head rebuilt. ďMight as wellĒ do the full valve job... guides... seals...
oh crap donít forget the lifters... sumbee, now we have to get the exhaust manifolds surfaced and the studs replaced...

for crap sake itís half apart so letís just do the other cylinder head while itís down...

a thousand + dollars later ....
 

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