WJ 4.7HO Rattle

[Trav_Patrol]

G'day folks,

I jumped on here the other day to research a potential purchase, which i went through with, I picked up a WJ today, it's done 215,000km, from the second owner, full service history, very tidy, I did my research and accepted some of the usual issues, struts, blend, etc, not a huge concern and easily fixed.
During the test drive it was beautiful. very smooth, both the engine and transmission, so i went through with it.
I've just gotten it home (about 45 minutes drive) and it has this horrible rattle, I did use the search function on here and have been reading for about an hour now, and am still going. But i thought i'd pop up a post with a video to see if anybody could help me.
I've had a pretty bad run with cars this year, bought two lemons already and lost a lot of money, i was very careful before getting this one and feel like I've just gotten another bad one. Cheers
quick edit, i have had my scanguage 2 on it, and it brought up no codes.

https://www.youtube.com/shorts/MtCYBaGMv48

[FARWEST]

Maybe remove the belt and see if the sound remains...will eliminate a few 'bits n pieces'....good luck

[layback40]

Where is the noise? Sounds like overhead gear.
I dont know anything about the 4.7 though!
Hope its got oil & oil pressure!
Good luck!

[Trav_Patrol]

Originally Posted by layback40

Where is the noise? Sounds like overhead gear.
I dont know anything about the 4.7 though!
Hope its got oil & oil pressure!
Good luck!

Oil pressure (assuming the gauge works correctly) is good, oil topped up and pretty clean.

[Jeeper6]

I had a WJ4.7 HO...one morning when I started it there was a god awful rattle...had no idea what it was thinking the worst of course. Seemed to come from the top / front of the motor.
I turned it off, started it again, the same noise. I had it tilt trayed to a local workshop for evaluation. The mechanic there had no idea, said to me "it's stuffed mate".
(He even tried to explain to me where the oil pump was blah blah blah, except he was totally wrong as the oil pump is chain driven in those things.)

I left it there and did some research...found nothing. The next day the mechanic called me and told me he started it and it was fine...noise gone.

I went and picked it up...all was good, drove fine no issues at all. When I thought about it and the noise, it was in fact like the sound of a timing chain dragging and banging inside the engine.
I figured that is what it must have been,,,being the 4.7 has chain driven overhead cams on each bank with hydraulic tensioners, I reckon one of the tensioners didn't come up with oil pressure allowing one of the timing chains to flop around and bang against the alloy housing making a racket. Being it came good and never did it again I left it at that.
Dunno whether the noise you experienced was the same,,,but is a thought...

[Trav_Patrol]

Originally Posted by Jeeper6

I had a WJ4.7 HO...one morning when I started it there was a god awful rattle...had no idea what it was thinking the worst of course. Seemed to come from the top / front of the motor.
I turned it off, started it again, the same noise. I had it tilt trayed to a local workshop for evaluation. The mechanic there had no idea, said to me "it's stuffed mate".
(He even tried to explain to me where the oil pump was blah blah blah, except he was totally wrong as the oil pump is chain driven in those things.)

I left it there and did some research...found nothing. The next day the mechanic called me and told me he started it and it was fine...noise gone.

I went and picked it up...all was good, drove fine no issues at all. When I thought about it and the noise, it was in fact like the sound of a timing chain dragging and banging inside the engine.
I figured that is what it must have been,,,being the 4.7 has chain driven overhead cams on each bank with hydraulic tensioners, I reckon one of the tensioners didn't come up with oil pressure allowing one of the timing chains to flop around and bang against the alloy housing making a racket. Being it came good and never did it again I left it at that.
Dunno whether the noise you experienced was the same,,,but is a thought...

IT does sound like that, i found another thread on a US forum, where the timing chain tensioner guides had worn out, they're made of nylon and the noise was the timing chain slapping the tensioner....I found a workshop not far from my work that specialises in Jeeps so it's getting looked at in the morning, fingers crossed it's not too bad.

[FARWEST]

Please let us know how it goes....will give forum members info and possibly a workshop we can relate to...cheers !