knocking sound in my 2.5 yj

[yj94]

I have a knocking sound coming from the engine someone said it might be the lifters but im not a mechanic anyone else have this problem

 

[Bounty__Hunter]

How loud is it?

Use a large prybar as a stethascope and you can really narrow down the source by holding the handle to your ear and the tip to varying locations on the engine.

The YJ 2.5L is prone to the front and rear studs breaking on the exhaust manifold, allowing an exhaust leak tick.

 

[yj94]

Its not an exhaust leak. it has a rhythm and goes away when rpm get higher I hope its nothing to bad I was hoping it was a lifter

 

[yj94]

How can I tell if its a lifter or something worse

 

[yo momma yj]

> it has a rhythm and goes away when rpm get higher

when rpm get higher, so do the oil pressure, so it could be a sludgy lifter.

look in your valve cover and see what the insides look like.

my guess is you changed filters & oil religiously?


a 3' piece of garden hose used as a stethoscope isolates sounds real good.

after the rebuild, get the breather out of the intake.

at 122K I had to do the head and replace all 4 exhaust valves from that numbnuts carbon dump design.

the aluminum valve cover condenses and doesn't help the matter.

 

[Bounty__Hunter]

How can I tell if its a lifter or something worse

Add a 1/2 to 3/4 of a quart of ATF to the engine oil. If it quiets down, it's a noisy lifter.

 

[yj94]

Thanks for the info I used the hose trick just a minute ago but couldn't pin point anything now im worried

 

[jfrabat]

Keep in mind that the 2.5L is inherently (sp?) noisy engine... lifter noise is kind of normal, so don't worry TOO much. Try the ATF trick, also, as it helps quite a bit.

 

[yj94]

Well I took it to the jeep dealer today and he said it was nothing bad it sounded like a bad lifter peck to him