XJ engine noise
10-13-2010, 12:04 AM
#1
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Year: 1995
Model: Cherokee
Engine: 4.0
XJ engine noise
i have a 95 cherokee sport and within the last 1000 miles or so started hearing a knock. its not loud but you can definately here it but i just cant pinpoint where its comin from. i changed the plugs and wires about 2000 miles ago and noticed white stuff crusted on them. i read that this could be caused by a leaky valve seal which could be the sound but my jeep dont smoke at all. please help i cant afford for my jeep to take a crap on me so i need to fix it soon.
10-13-2010, 12:12 AM
#2
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Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
remove the drive belts and then start it up this takes all poss of the noise coming from the water pump power steering alt and all turning acc on front of motor dont let it run long then go from there
10-13-2010, 12:49 AM
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Model: Cherokee
It is just the drive belt for the accessories. Waterpump, P/S pump, Alternator, A/C (if equipped). You are thinking of the timing chain which is under the timing cover - this is not what he is saying to remove.
10-13-2010, 03:03 PM
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Year: 1995
Model: Cherokee
Engine: 4.0
i know none of those things will make white stuff on the spark plugs so i need a real answer to that problem ive already ruled out a lot of things i know for sure the sound is from inside the motor just dont know where. back to my original question will a worn valve seal make any noises and if so does it always make your jeep smoke like its burning oil.
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10-13-2010, 07:52 PM
#8
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Year: 1994
Model: Cherokee
Engine: 5.2
Hey he was just trying to pin point the problem for ya, so that way u don't waste hundreds of dollars and hours to find out your water pump was ticking. And what do you mean by "white stuff"? Could be normal, how old are your plugs, are you loosing oil? Does the knocking noise only happen when going up hills under a load? Could be anything from bad bearings to not getting enough fuel and having spark detonation.
10-13-2010, 08:02 PM
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Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
ok here we go valve seal on all motors ive rebuilt in my 30 years of auto repair ar plastic or rubber like material if they go bad you will burn oil and smoke the white crusty stuff could be the motor is running to lean your plugs should be light to dark gray maybee thats the color if you sure the motor is knocking rebuild it blue smoke is oil white smoke is water ive had people swear the have a knock in their motor garages say yhe need a motor they will put one in for 2,500 and up came to me pulled the belt you find out **** like water pump beasrings idle pully bearing bad harmonic balancers i fix it and away the go
Last edited by freegdr; 10-13-2010 at 08:06 PM.
10-13-2010, 11:25 PM
#10
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Year: 1995
Model: Cherokee
Engine: 4.0
maybe its a bearing knock then and its just startin out i know for a fact its not anything up front like the water pump and all that cuz i can point the sound out to be comin from the back of the motor could be from the rear main seal i put in about a thousand miles ago but i made sure i didnt touch the bearings or crank i guess somethin couldve blew up and hit it but i tried everything i could to make sure it went smoothly
10-13-2010, 11:32 PM
#11
Does it knock at idle only? Or will it get worse/louder with engine speed?
Knock only cold? Or knocks when hot as well?
How many miles on the engine?
The lifters in these things love to tick or knock if its collapsed. If it only knocks when cold you may have piston slap issues. If it gets worse with engine speed then it could be bearings.
Knock only cold? Or knocks when hot as well?
How many miles on the engine?
The lifters in these things love to tick or knock if its collapsed. If it only knocks when cold you may have piston slap issues. If it gets worse with engine speed then it could be bearings.
10-14-2010, 07:02 PM
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Year: 1995
Model: Cherokee
Engine: 4.0
its got 175k it seems to get louder as it warms up the loudness stays about the same through at speeds and rpms but im not sayin its to loud its noticeable but not loud just hopin to catch it before it gets bad
10-14-2010, 07:11 PM
#13
How is your oil pressure at idle and while driving?
Easy thing to check would be your flex plate. There is an inspection cover on the bell housing. What you are looking for is cracks in the flex plate around the bolt holes. That seems to be a common issue.
For giggles I would check the compression, motor might be a little worn out.
Easy thing to check would be your flex plate. There is an inspection cover on the bell housing. What you are looking for is cracks in the flex plate around the bolt holes. That seems to be a common issue.
For giggles I would check the compression, motor might be a little worn out.
10-15-2010, 11:07 PM
#15
Thats not horrible but its on the low side. If it does not get cold there (below freezing) then you can run a thicker oil and/or Lucas oil stabilizer. If you really want to pin point the noise grab a stethoscope and check around the oil pan, lifter galley and flex plate.