strange noise coming from air fiter box

[kevin phillips]

have a 06 f-550 that has a thumping noise coming back through the air filter at idle and at higher rpms.A thump,thump noise rythmic to the engine.It gets louder when the air filter is removed almost like it is backfiring through the intake.the vehicle had heads replaced recently for coolant in the combustion chambers.the engine is not missing and seems to perform fine with no misfiring just the noise in the air box.the noise sounds like some of the trucks do when you let off the fuel after a hard accel but this truck does it just idling.any ideas guys on where to go or what to check? thanks

[DwayneGorniak]

Have you done a power ballance or relative compression test on it? Sounds a little like a push rod.

[Jeff_E]

At my last dealership a tech had one with a similar concern. He determined it was coming from the drivers side by taking off the throttle plate adapter elbow and sticking a stethescope hose inside in to each side of the intake with the engine running. I thought that was pretty clever, but then he took the cab off, and both heads off TWICE without finding anything wrong /forums/images/%%GRAEMLIN_URL%%/hitthefan.gif, no bent push rods, he even took the valves out of that head and found nothing. Then he quit and I got stuck with it. After digging a little deeper I found one of the roller lifters for cyl #5 rotated in its bore and wiped out the cam. I hope this helps, let us know what you find.

[kevin phillips]

ran power balance and relative compression diddn't find any problem.customer had to have truck bringing back next week

[OHNO60]

SAME DEAL HERE! 2006 E350 POPPING OUT OF AIR CLEANER.POWER BALANCE PASSED,KOER,KOEO ALL PASSED. REMOVED INTAKE MANIFOLD AND STARTED ENGINE.FOUND LIFTER DAMAGED. ENDED UP REPLACING BLOCK.

[kevin phillips]

engine bent a pushrod number 7 cylinder

[RJP]

Did you replace push rod? May have a valve stickig. Might not make it out of the lot or come back soon.

[Mekanik]

Did you replace push rod? May have a valve stickig. Might not make it out of the lot or come back soon.

That has to be a really stuck valve to cause a pushrod to bend. But there has to be a reason why it got bent.

[Bruce Amacker]

I heard of stuck valves/bent pushrods several times on the early 6.0s, caused by "lot rot". I haven't heard of one for a while. I wonder if they're putting a couple thou more clearance in the guides.

 

 

/forums/images/%%GRAEMLIN_URL%%/scratchhead.gif

[Tony302600]

Go look thepicture of a 66 mile 6.4 pushrod in the 6.4 forum...now thats bent. /forums/images/%%GRAEMLIN_URL%%/cheers.gif

[kevin phillips]

it had heads recently put on, was told that if engine crank pulley wasen't in correct position i.e. 6 o clock that the pushrod could bend while the heads were being ran up but if it stuck a valve then it isn't stuck now .it ran ok guess i'll know in a month or two. thanks for all the help guys.if anything happens bad i'll post it

[kevin phillips]

i found out which cylinder by removing the intake and blocking the turbo oil feed and cranking the engine over .it was very clear which cylinder was blowing instead of pulling air.engine just at crank speed,ficm removed.

[ktmlew]

i found out which cylinder by removing the intake and blocking the turbo oil feed and cranking the engine over .it was very clear which cylinder was blowing instead of pulling air.engine just at crank speed,ficm removed.

How did you block the oil feed? Looks like I'm about to jump back in the dealership...interview Monday!

[LARRY BRUDZYNSKI]

Quote:

Looks like I'm about to jump back in the dealership...interview Monday!

ARE YOU FRIGGIN CRAZY!!!! /forums/images/%%GRAEMLIN_URL%%/boink3.gif

[RJP]

Quote:

How did you block the oil feed? Looks like I'm about to jump back in the dealership...interview Monday! [/quote

]

I bolt a piece of still to the line were it bolts to the turbo after removing the turbo I also driled and taped a hole in the middle for a pressure gauge and/or apply air pressure.

Ford also has a letter out that said you must start and run untill warm, move truck 20 ft.and move auto trans through all gear positions somthing like every 2 weeks on the 6.4L to keep from valves from sticking.

Quote:

[ktmlew]

Quote:

Looks like I'm about to jump back in the dealership...interview Monday!

 

ARE YOU FRIGGIN CRAZY!!!! /forums/images/%%GRAEMLIN_URL%%/boink3.gif

Well? That goes without sayin...finally realized it's not the end of the world if you don't turn 40hrs every week. One thing that has helped is enough of the older guys quit that the dealers had to start paying better to keep decent help. So now I can probably make almost as much turning high 30's as I made doing 45-50 a couple of years ago.

 

I know it's gonna suck like a Hoover the first six months or so but have to do it! /forums/images/%%GRAEMLIN_URL%%/poke.gif /forums/images/%%GRAEMLIN_URL%%/hitthefan.gif

[kevin phillips]

i just put the oil feed back in oil cooler then fabbed a piece of aluminum to fit line where it goes to turbo,used a old gasket and a couple bolts it really worked good to find cylinder called the guy today ,all is ok with the truck so far