2004 EB noise on cold start

[jonnyk]

I have a 2004 EB that I bought used about a year and a half ago. The vehicle has been good and I really like it in spite of having to replace a few things such as the rear struts - springs were broken, speed control cutout switch - causing ABS light to come on. Other than that it's been regular maintenance - oil and filter every 5k, tires, brakes, all fluids changed recently as well including F & R differential, transmission, transfer case, PS & brake fluid etc.
I have spent much time on this forum and the information has been invaluable both before my purchase and after to help with problems that I've had. This is also my 1st post here.
Recently I have had an issue with a vibration/noise that occurs only at startup when the vehicle has been sitting for longer than say 12 hours. It is definitely coming from the engine. I have also replaced the starter thinking that the starter drive might be been hanging up. The sepentine belt has been pulled and all the pulleys, idlers, pumps etc. seem to turn fine with no binding. This noise is very startling and loud and I fear something serious is going on and is eventually going to get worse. The noise/vibration last for only a second or 2 then goes away and doesn't come back until the vehicle sits overnight or longer and then it will do it again. Only the 1st time it's started. After it starts that 1st time it is fine.
I appologize for the long post but I'm looking for some help with this and after searching the forum and not coming up with anything that seems to directly apply to my situation I figured I would put this out there and see if anyone else had experienced this.
Oh yeah, I have the 4.6 4WD with 99k on it. I bought it with 65k and I would like to keep it for a while longer. My daughter will need a car soon as she is getting her permit this week so no new cars in my near future

 

[matt0248]

Sounds like it could be the timing chaing tensioners. They use oil pressure to tension the chain. When the engine sits for a long time the oil bleeds out and has to fill again. This happens within the first few seconds of starting the engine and buildig oil pressure. There are threads detailing their replacement floating around here somewhere.

 

[jrford]

here is another idea, what filter are you using?
Try a motorcraft filter 820s (OEM). Cheap filters will allow the oil to drain back into the engine, therefore it might take a second or two for the oil pressure to build up. Timing chain have been described as sounding like marbles rattling around. Filter idea is a cheap test, also use motorcraft oil 5-20w just for testing. I've got 100k on mine . . just an idea.

 

[jonnyk]

matt & jr thanks for your suggestions.
I have been using the Motorcraft filters and Motorcraft 5-20 oil exclusively since I've owned it. I am going to try a different oil/filter combination next time I change it which should be this weekend. I was thinking of trying the NAPA gold filter and Mobil 1 full synthetic to see if that may make a difference. Does anyone have experience with running these in their Explorer with the 4.6 ?
jr. When you mentioned that the timing chain tensioners sound like marbles rattling around in a can that is exactly how it sounded 1 time. This was the worse sound it ever made and lasted a few extra seconds. I am thinking that the tensioners will need some attention if the oil/filter don't make a difference. I will try to find threads on the replacement procedure.

 

[jonnyk]

Well I just wanted to post an update to my situation - I changed oil to full synthetic Castrol 5w-20 and NAPA gold oil filter. So far with about 2 weeks on the new oil/filter nothing has changed. Loud noise at start-up still occurs when 1st started from cold (sitting for 12+ hours).
I may try motor oil flush at next change. Has anyone tried this and if so, what product have you used?

 

[fusseli]

Have you considered trying some seafoam in your oil before you drain your oil next? In the off chance that something is gummed or clogged up, that might fix it.

Also... is there any way that you could post a youtube video or something of the noise? All in all, I have been led to believe that the 4.6L is a very reliable engine and should last forever if properly cared for, which it sounds like you have been.

 

[FordFool2]

JohnnyK, we are in pretty much the same boat together. My '04 EB has 113K miles and I would like to give it to the new driver in my family. I hear some noise at startup, thinking the worst, it could be the cam tensioners. I thought that was more prevalent on the 4.0s, not the 4.6s.

I'm thinking more along the line of the belt idlers and tensioner. Helped a friend the other day on a 5.4 with 100K and I could tell the new pullies were much smoother than the old ones.

Maybe you could run a test. Let the truck sit the prescribed amount ~ 12 hours. Remove the serpentine belt and start it up, just for few seconds. If you hear the noise, then internal issue. If no noise, we have it isolated to the belt train.

 

[jonnyk]

Guys, thanks for the ideas.
I have never used Seafoam but am willing to give it or something like it a shot next time I change the oil and filter.
FF2 - From what I have been reading here on the forum I agree it does seem like the timing chain tensioners are more of an issue with 4.0L and not the 4.6L. I was originally thinking that it might be a pulley, idler or pump driven by the serpentine belt. I did remove the belt and checked out the pulleys, idlers, PS pump, AC comp., water pump etc. all seemed fine - but that may not mean that something isn't siezing up a bit when it sits for a while. I like the idea of removing the belt and starting it when cold to see if noise remains.
I will post back here when I have more info.

 

[fusseli]

If you Seafoam in your oil, you'd want to add a partial can in your old stuff then run it for ~60 miles or so, then drain and change to fresh oil. Just making that clear.