6.0l bent valve broken rocker
 

Ok, first off I have to say this is a great site for expert advice. I have used it several times for work until the military thought it was a good idea and now the site is blocked at work. Now I have to work at home at times for good advice. That being said, here is my current issue. I recently replaced head gasket, front and rear seals, new oil cooler and numerous other gaskets and "O" rings on our 2003 F350 with the 6.0l. After I got it all back together I started it up and let it run for a minute or two. I had a miss and a little popping noise as if it was coming from a valve. At first I thought maybe an injector still had air in it so I reveved it up a notch. Well my small hiss and pop turned into a load banging. I pulled the valve cover off the passenger side and found a bent push rod. I replaced it wih new but failed to inspect the rocker arm first. I put it all back together again only to still have the load banging noise. That is when I found the broken rocker. Both items were on the exhaust side. So, two questions. First, why did they bend and break? I torqued everything to spec. I was VERY adament about following instructions. Second question. Can I reuse the one head bolt that I removed? Engine only ran for a moment or two. Would that make a difference? Ok, that was three questions. Now I haven't put it back together yet and I'm hoping the broken rocker arm was my load noise. Thanks again in advance for all the great advice.

Is there any way that the motor went out of time? Usually push rods and rockers get bent when the piston pushes a valve up. I would go through your valve set up again. Make sure your on tdc#1 piston both rockers should be loose, follow valve adjustment. Turn the motor 180deg. Then do the other ones. The two valves that had problems i would try to check them and make sure they are not bent or broken off. Mabye take the rocker arm off and pull up on the head of the valve. And find a way to push it down on it without letting the valve keepers come off. Reusing the bolt shoild be fine, i am suprised u went through all that and didnt do head studs to avoid further head gasget problems that are comnon in these trucks.

Unless the cam gear as removed, the motor will still be in time, as in the cam opening the valves in synch with piston movement. Although I'm not so certain what kind of damage can result from not torquing the rockers in proper sequence.

Was it one valve or two? If it's one, are you certain the valve spring is seated properly? A spring not in the pocket could bind and bend/break stuff.

Just taking stabs at logical possibilities. :humm:

Iv'e seen this happen 2 times after headgasket install, I bought a complete motor, not running for $500 it just had new headgaskets installed and it broke a rocker and had bent pushrod, the second one was at a buddys shop and he sent the motor out to be rebuilt and when they fired it up same thing happened, confused how this could happen I came home and went throgh the process on the spare motor.
After just dropping the pushrod tubes in I went and checked how they were sitting in the lifter,and there it was, one of the pushrods was sitting up on the lip of the lifter and not in the pocket so I installed that rocker assembly and it stayed right there on the lip, if I were to try to start that engine it would have failed.
When you drop the pushrods in pick them up a little and let them down and make sure it seats in the pocket.

Do not re-use that bolt. I have extras if you need some, but once they're torqued, they' basically junk after that. They're stretched to yield to hold that clamping force.

Cfarley, nothing to adjust, it's hydraulic.

My guess is it just wasn't set in there right like Bob said.

Because I have a full view of the lifter valley when assembling my gas V-8s I never considered that the push rod not going into the cup right as a possibility. :tu::c:

Ive seen this happen before after a hg replacement. The push rod wasnt seated in the lifter and caused a badly bent push rod and broken rocker, the push rod guide in the hg was also ruined and there was a nice valve indention on the piston. Always double and triple check and quadruple check your pushrods when going back together.

Thanks for all the suggestions and ideas. Tomorrow I will be extra carefull while assembling the engine. Thanks Mdub707 for the offer but we already bought a new set of bolts for the right bank. I sure hope this works. Peace!

Probably too late asking now, but was there a reason you didn't just use ARP headstuds? :pca1:

Let us know how you make out with it!

I checked the price on them and couldnt justify spending that much of tax payers money. I'm sure it would have been the better choice but we are on a REAL tight budget now.