While driving at 60MPH, constant load, my 2003 E350 7.3L (4,900 miles) developed a loud, machine-gun, rat-tat-tat noise and loss of power. I had to drive about 3 miles to get off the freeway with what sounded like the engine coming apart. When I pulled to a stop at the bottom of the offramp, the noise suddenly stopped but the engine continued to miss and ran at about 2/3 power. One of LA's biggest dealers found the #2 cyclinder with two broken rocker arms and pushrods. Dealer replaced the broken push rods, broken rocker arms, #2 injector and misc. seals/o rings, new oil & filter. 6 miles from the dealer it failed again....same noise/symptoms but this time a cyclinder in the other bank. Dealer is stumped. After they fixed it the first time they drove it 50 miles without a problem. I started it at the dealer and drove it 5 miles to a stop. Then restarted and drove 1 mile before it failed again. Someone suggested this is an injector problem causing one cyclinder to go hydraulic and reverse loading the valve train. No fault codes on the ECM. Can't get anyone at Ford to go deeper than just fixing the broken parts again. Regional tech rep. has no solutions. Any experience/ideas out there? Thanks,
David

 

I would call Ford higher up and get me a new motor, that is ridiculous. I would think they would like to bring that one in and see what the flaw is on it. I hope you have better luck!!

 

This is no injector problem. If the cyclinder hydraulic the con rod wuold bend or break and go outside the block. It sounds like valves are sticking when the head gets up to temp.. If they won't put in a new engine, they should at least pull the head and check valve guides. I've run into this problem before with 3500 series and 3412 caterpillars. Sometimes people don't use the right oil or machine shops don't reem the guide to the proper size. Let us know what happens.

 

Either its faulty parts or look in the area of the cam. Maybe the camshaft is "walking" and is the cause of the problem. I have never seen that though. Could be lifter problem as well.

 

It must be something that all the cylinders have in common. Are you the original owner? Has the engine had any major work done in the past? What about your engine oil- has it ever had fuel in it or run low? I think that 700hp may be on to something with valve guides. If the pushrods were bent it means that the cam tried to move them but they would not move. That means that the rocker arms are sticking and or the valves are sticking. maybe an oil passage is being plugged also? I am very interested to see what it turns out to be.

 

First, thanks to all of you who repsonded with your ideas. I am the original owner, the van had 4,950 miles when the first cyclinder pushrods/rocker arms broke and then 5,006 when the second cyclinder in the other bank broke, and there has been no maintenance/repairs other than the 1st oil change at 3,500 miles and then again as part of the first cyclinder repair. No fuel or coolant in the oil. Ford went ahead and repaired it again by simply inspecting the head and replacing the broken parts. Things will heat up tomorrow because I want Ford to demonstrate that they know what caused the problem and will fix it. 3rd time here in Calif and it's a lemon and Ford will own it. David

 

dcverde,
Was the vehicle sitting unused for any length of time (you don't have many miles on it for a 2003 model). The reason I say this, is my mechanic, an experienced person with 7.3's, says that if a 7.3 sits for any longer than a month a sticky film can form around the valve guides, making it hard for the valves to open, and then bending the push rods. The only way to fix it is replace all the valve guides, and clean the valves with some fuel to remove all the sticky film. Keep us posted on how you go with Ford, and good luck.

BigF350

 

dcverde-
Were the pushrods bent or did it look like something came loose?

 

In response to a question, yes the van did sit for a few weeks prior to the first failure and then again for 10 days at the dealer after the first fix before the 2<SUP>nd</SUP> failure. I don’t understand how if the valve stems/guides did gum up, why did the first failure happen after 1 ½ hours of freeway speeds when the temps had been normalized for almost all that time. Why didn’t it happen shortly after startup?

After a long morning with the dealer’s service manager and the mechanic who did the work, I now have the van back but I have no confidence that the cause has been identified, only the damage fixed. I don’t recall what Ford calls his level of training but he is their most senior level diesel mechanic. Both he and the service manager spoke with Ford’s Hot Line rep. who would not authorize the replacement of the heads which was approved on one of the other vans I tracked down with the exact problem, mileage and failure timing. Both of my repairs included removing the heads (both since the second time it was the #3 cylinder), replacing the broken rocker arm (and the paired, undamaged one) and the broken (not bent) push rod, and although not apparently damaged, a new injector and seals were installed. The mechanic inspected all the other pushrods and found none bent/damaged/rubbing. With a compression device he checked all of the other valves and found none binding or signs of scoring on the valve stems. He was advised by the Hot Line rep to check the heads for casting defects which could cause the pushrods to bind and found none and found no signs of contact between any of the valves and pistons. Ford believes I simply ended up with defective rocker arms and/or pushrods, what was going to break now has, and I should be a content, albeit somewhat inconvenienced, Ford owner. I think the lottery has better odds than any of this being true. If it breaks again, under Calif. law, Ford will own the van for my full purchase price less a nominal mileage deduction. I’ll post back either when it breaks again or I get past 10,000 miles, after which it appears this problem doesn’t happen. If it was a valve guide problem, maybe they open up enough by then?

 

It's been 5 months and since I last posted on this problem and I'm pleased to report that after Ford replaced the broken push rod and rocker arm (for the second time but on the other bank) I've put 6,000 miles on the van without further problems...just like Ford said. I still don't believe it was a simple coincidence but nevertheless replacing the failed parts seems to have solved the problem. Thanks to all who responded to my initial request for help.

 

i bet its got a stuck lifter mine did it a few months ago and it had two siezed up lifters in it. Gotta pull the head to get to the lifter, i would be willing to bet its the lifter over a stuck valve. They need to check the lifter hold downs, if they get bent that will cause the lifter to stick also, if its busted some tubes i bet the hold downs are damaged also.

 

Ford never mentioned stuck lifters although it makes more sense than a stuck valve. They removed the heads to change the broken pushrods and rocker arms but did not replace lifters. As I mentioned in my previous post, it's now been over 6k miles and no further problem.