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Another Rocker Arm Failure

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It's a 2008 6.4L with 88,000 miles, misfiring and smoking badly due to a broken y-pipe. Cylinder #1 intake rocker failed at the fulcrum. The ball shows some wear and the socket in the rocker has split on both sides. I found the rocker, ball and the clip laying on the head. The pushrod is in excellent condition. The valves are fully closes and freely open and return so that is not an issue which I expected as if this were the exhaust side things might be different.

 

I looked at other rockers and found them to be perfect. I pulled the turbo oil feed banjo bolts looking for signs of poor maintenance but found no crust. So I am approaching this as a simple isolated part failure. Anyone else see this?

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I'd be checking cam lobe lift on the affected cylinder... Both of the times I saw the problem, the affected cylinder was #1 and both times the cam showed significant loss of lift measured at the lobe. Both times, the concern appeared to be a rocker arm concern and, IIRC, both engines had an odd squeak coming from the right front corner.

 

The time I did it, I had to replace the cam... the time another diesel tech did it - he got to put a motor (lucky shit).

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I have seen alot of these lately. Replaced the broken rocker arms and checked for correct valve train operation. I have had no problems just replacing the broken parts yet. I have ran into a few were there was lifters that were damaged but cam was ok. Replaced lifters and rocker arms.

 

Now we are seeing alot coming in where the tips are badly worn and digging into the bridges and all the rocker arms are loose and about to fall off it appears.

 

These engines are absolute crap and I had someone tell me the other day that he wished he would of kept his 6.0 liter.

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I'd be checking cam lobe lift on the affected cylinder... Both of the times I saw the problem, the affected cylinder was #1 and both times the cam showed significant loss of lift measured at the lobe. Both times, the concern appeared to be a rocker arm concern and, IIRC, both engines had an odd squeak coming from the right front corner.

 

The time I did it, I had to replace the cam... the time another diesel tech did it - he got to put a motor (lucky shit).

Might be a good time to employ a borescope.

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Now we are seeing alot coming in where the tips are badly worn and digging into the bridges and all the rocker arms are loose and about to fall off it appears.

 

 

Funny you mention that. Pretty much all 6.4L engines I've have the valve covers off of, have worn the ball pivot off almost completely where it contacts the valve bridges. Yet on 6.0L engines with equal or higher mileage they all seem intact. The design setup between the two are almost identical. What gives?
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Here comes a SWAG... the 6.0 has HEUI injectors that spill oil into the rocker box (along with whatever comes up the push tubes). Some of this oil is going to wind up as mist that will help lubricate the valve mechanism.

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This makes me wonder if this is why Ford designed the 6.7L with individual push rods and rockers for each valve... with no bridge and a flat tip... along with a lubrication manifold and jets to lubricate (and cool) the valves and rockers.

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Let us know how that one works out. I had the same thing and that truck put on 80 miles before coming back. I could move the valves the rocker and ball were intact the rocker was cracked in half

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I have one in the bay right now that I took apart before going on vacation, a 2008 F550 rescue truck 93K 5372 hours, they said they were in no hurry for the truck so they give it to me to tear apart and then let it sit a week. Really makes you want to come back after a week off. Engine has lots of thick sludgy oil on the insides of the valve covers. They were changing the oil, it has had 17 oil changes in 93K and 5300+ hours, and they found a small metal clip stuck to the drain plug. It was the clip on the end of the rocker arm pivot. FSE and hot line says not caused by lack of maintenance but probably caused by running too hot and to check the thermostats and cooling system per the TSB, WTF??? Posted Image My calculations say it should of had around 27 lofs. All rockers tips and balls, bridges, push rods worn. Replaced them all cleaned out the goo as best as I can. Start it up and have a skip on #7. here popping out intake and relative compression is down 15% on #7. Took the valve cover back off to see if I missed the push rod or bridge location, all is ok. If the idle is raised there is a loud rapping in the engine. Valve lift looks ok but I can't wiggle the #7 intake rocker like the rest when the valve is closed. Any one run in to issues like this on the POS engine? I am thinking stuck lifter due to sludge or valve recession. I fucking hate these 6.WHORE engines. Posted Image Give me a E Series 6.0 any day of the week to work on. Got E 350 sitting outside with roller beings in the pan and no oil pressure. Another short block for this one. Posted Image

I have never seen this type of rocker arm wear on the 6.0s.

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I'm thinking the valvetrain oil feed rails in the 6.7 are a direct address to this concern. I just did the 6.7 course, and it seems to me they have directly addressed alot of common problems we have seen over the past 7 or so years.

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I've heard there is a valve train service kit out there for the 6.4L I've used the one for the 6.0L which gives you all new push rods, rocker arm assemblies, valve bridge carriers and head bolts. You remove one head bolt at a time to perform.

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The 6.4L does not require head bolt removal to service the rockers. They are mounted on separate plates bolted to the head under the fuel rails. You can order individual parts or a complete rocker assembly for each cylinder that comes with the plate, fulcrum balls, intake and exhaust rocker arms and the plastic clips. I didn't see anything resembling another kit in the parts catalog... doesn't mean it's not out there though.

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Still waiting on back ordered parts to arrive but I wanted to update you guys - After further inspection I discovered most of the rockers have worn out and binding valve bridge balls... or whatever they are called.

 

Speaking of back order parts, is it true that the high pressure fuel pump is now on back order? Our parts guy says we only have one in stock and that they don't know when they are going to restock.

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Just want to update this topic: Inspection of ALL rocker arm tips revealed wear on every one. Most no longer rolled freely by finger tip and many were worn down leaving the contact point level with the rocker socket.

 

In the image below, the rocker on the left is from the #1 intake and as you can see the tip is missing. The rocker on the right is from the same engine and you can see that the tip is worn. As this continues to wear the retainer will eventually let go and the fulcrum will eventually contact the mounting plate damaging the rocker and or causing the rocker to eject from the assembly.

Posted Image

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