Just Brought 98 EB $500 With Engine Noise

[SPreston2001]

Hey guys I just picked up another 98 Eddie Bauer for $500 bucks from this old lady but it has some engine noise. I made a video and was wondering if you guys could take a look at it and tell me what you think the problem is. If need be, I know a place that will rebuild it for about $1800 bucks. The truck still runs and doesnt appear to have any trouble besides the knocking sound. Check out the vid.

http://www.youtube.com/v/VZQtajBCVaY&hl=en&fs=1

 

[djljr]

The engine is probably 4.6L SOHC V8? How many miles? A noise like that is difficult enough to diagnose when you are right there listening to it. I suggest getting a stethoscope and determine if the noise is coming from the top end or bottom end. Sounds a lot like valve train noise to me, like a flat cam lobe, but it could be anything. Is the oil pressure normal? I would also suggest removing the oil filter and cutting it open to look for bits of metal. If you find metal you can determine if the metal is ferrous or non-ferrous. Don't use a hacksaw to cut open the filter because that will generate metal shavings. Check compression and see if you have a weak cylinder.

 

[GRIP]

it could be anything from a spun main bearing,warn out wrist pin or other wise hard to tell from the video.

 

[SPreston2001]

Thanks guys. Engine is a 5.4L with 106K on it. Like I said the truck runs great, accelerates good, but that knocking noise just drives me crazy. I will invest in a stethoscope and try to pin point the exact location of the noise. It definetely sounds louder towards the bottom of the engine but then again I could be wrong.

 

[JUST4FUN]

could be as simple as an exhaust leak/broken boltif this truck lived in a a state where they use salt to deice

 

[braduardo]

Does the knocking go away after a few minutes? If so, it's possible that you have an exhaust leak that goes away once the exhaust heats up and expands. I think that happens with mine. I'm not around a computer with sound, so I couldn't actually take a listen.

 

[GRIP]

a exhaust leak is more like a ticking sound. not a knock.i'm going to listen to the video again and see if i can pin point it.

 

[SPreston2001]

Thanks for all the input guys. It doesnt sound like a tick, my XLT had an exhaust leak so I know that sound. When I had the oil changed today, I had them inspect the oil and they said it looked great and didnt find any shavings. Does the dreaded piston slap sound this bad? This clanking/knocking sound really takes away from the beauty of the beast!

 

[GRIP]

yea when the wrist pin on a piston is warn it sounds bad. almost like a diesel.

 

[cardude427]

I got the same issue with mine ( '97 Expedition EB with 173000m)but the problem generally goes away after a little bit of driving. I think it is piston slap but it could be valve related. I live with it knowing I'm going to drop in a rebuit sometime in the future.