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Subject: sticky valve?/4.6 triton

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lonestarjeff    Posted 11-29-2018 at 16:18:53 [URL] [DELETE]        [Reply] [Email]  
  • sticky valve?/4.6 triton
  • I suddenly have a single rat-a-tat-tat under the hood of my F-150. Louder at start-up, but continues only under acceleration. No noise at idle. Any ideas on what I'm dealing with?


    steveVa    Posted 11-30-2018 at 15:14:19 [URL] [DELETE]        [Reply] [No Email]  
  • Re: sticky valve?/4.6 triton
  • Does it tap tap tap when you first start it up even at idle??
    We had a 2006 Mercury Marquis that did that and I changed the oil and it cured itself. I figured it got some trash that clogged some oil to a lifter?? Don't know, but it went away and I was happy. Good luck.

    lonestarjeff    Posted 11-30-2018 at 22:13:59 [URL] [DELETE]        [Reply] [Email]  
  • Re: sticky valve?/4.6 triton
  • No tapping at idle, or even revving up on the driveway. I can only get the tapping driving under load. Not sure what that's about.

    Bruce(OR)    Posted 11-30-2018 at 12:02:45 [URL] [DELETE]        [Reply] [No Email]  
  • Re: sticky valve?/4.6 triton
  • I did some research. I liked this one the best. Hit the link and do some reading yourself.

    "started out a rattle like a lifter clicking. got louder and wen't to dealer for tear down of right valve cover. Mechanic came back with cam cover from rear of head and journals were worn and blue. Said I needed a new head, blamed wrong oil? After new head installed they heard a bottom end knock. The trust bearing was gone and crank was moving back and forth. The metal from cam dropped down and tore it up. New motor at $5700 for rebuilt long block. Told me the cam tensioner pads were worn out also. Since this happened i found out the oil pressure gauge is basically an idiot light as it moves to 40lb and stays there regardless of actual pressure. There was no way I could have known the pressure was down due to this gauge. It takes about 60 to 75K for this to happen. Ford would like this to go away offering no help whatsoever. I am hoping a class action will start but I might be too late. After six months the new motor started rattling at start up after sitting for a few days. It was the cam tensioners bleeding down and the chains rattled till pressure came up. The dealer said it was normal and showed me the door. I wen't down the street and bought a Ram with the Hemi and I am thrilled."

    - Bob G., Grants Pass, OR, USA

    lonestarjeff    Posted 11-30-2018 at 22:11:20 [URL] [DELETE]        [Reply] [Email]  
  • Re: sticky valve?/4.6 triton
  • Yes, I read quite a few horror stories on the F150 forum on tritons with way fewer miles than mine. One guy found a piece of gasket stuck in one of the oil jets under a valve cover. With 225k miles it could be almost anything.

    dave#1    Posted 11-30-2018 at 08:26:46 [URL] [DELETE]        [Reply] [No Email]  
  • Re: sticky valve?/4.6 triton
  • Wouldn't think it's a valve, sure that would be a interferes motor meaning the piston would hit the valve if it was open even a little bit.
    Might want to look at your spark plugs, some of those 4.6/5.3's had problems with the spark plugs blowing out of the heads and might sound like a ticking/ banging noise.

    lonestarjeff    Posted 11-30-2018 at 22:05:04 [URL] [DELETE]        [Reply] [Email]  
  • Re: sticky valve?/4.6 triton
  • I'll check 'em, but pretty sure it's not a plug. The truck is running really well(other than the tapping), gas mileage is around 17mpg(which is great for this truck).

    Farmer Dan    Posted 11-29-2018 at 19:50:50 [URL] [DELETE]        [Reply] [Email]  
  • Re: sticky valve?/4.6 triton
  • guess it could be a valve. Do you have a stethascope?

    lonestarjeff    Posted 11-30-2018 at 22:00:03 [URL] [DELETE]        [Reply] [Email]  
  • Re: sticky valve?/4.6 triton
  • No scope, but it wouldn't help anyway since I can't get the engine to make the noise until I'm driving.

    Bruce(OR)    Posted 12-01-2018 at 00:26:07 [URL] [DELETE]        [Reply] [No Email]  
  • Re: sticky valve?/4.6 triton
  • Does sound like the cam phaser. Then again could also be the chain guides with the timing chain bouncing off of them. A trade in might be in order or a cost estimate to replace guides and such. Then you figure it out.
    I have seen quite a few 2000 4.0 Fords with noisy engines. Run them long enough and it should get real noisy, run ratty and then go poof.

    lonestarjeff    Posted 12-04-2018 at 00:19:31 [URL] [DELETE]        [Reply] [Email]  
  • Re: sticky valve?/4.6 triton
  • I've been researching all the triton timing chain foibles. From what I'm reading the symptoms/tell-tale noises described for worn chain guides, phasers, or tensioners don't seem to match mine. Not exactly a scientific analysis, just my impression.

    If I could make the space & find the time, I'd like to pull the front cover to see what's going on.

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