Strange Noise

[Outlaw]

A little back story first to make sure I pre-answer some possible questions...
I bought my 88 XJ in November, prior to purchase it had sat in the same spot since october of 2006:headshake: When I purchased it it would not start. Towed it to the house and since have replaced the Plugs, wires, Cap, rotor, fuel pump (twice) and the air filter. I finally got it up and running and as said in a previous post stole the plate off my van and drove it to the gas station. The trip was smooth and uneventful. On the way back however I started getting a strange humming/whining noise coming from the rear. First thought was great something wrong with the gears... Pulled into the driveway and stopped the noise was still present... assuming not the gears. Got out and walked to the back and put my hand on the gas tank thinking the (2nd) new pump i just finished installing was making a noise... I could feel a vibe on the tank, so I turned off the jeep and turned the key back into the on position and couldnt hear anything but the mild hum of the pump.... started it again and it returned.... I cant see any possible exhaust leaks.... any thoughts???

[XJ4IV]

think you could load a video of said noise? Ive had several folks while out wheelin come up to me and tell me Ive broken a bead on my tire... so ME not being stupid decide I need to analyze it to make double sure ... My fuel pump is SOOOO loud but it does sound like a tire is leaking, is that the noise your hearing?

[Outlaw]

i'll try to get a video of it tomorrow morning... it honestly sounds like the whine that a T-case going out or bearing going out makes, except when standing still..... hoping its just the pump or exhaust vibrating but I will get a vid in the morning.

[oderdene]

think you could load a video of said noise? Ive had several folks while out wheelin come up to me and tell me Ive broken a bead on my tire... so ME not being stupid decide I need to analyze it to make double sure ... My fuel pump is SOOOO loud but it does sound like a tire is leaking, is that the noise your hearing?

I also heard sound like tire leaking in back of my lovely full 2 years and thinking about new fuel pump ordering, understood from your post, nothing to worry :D

[Mudderoy]

i'll try to get a video of it tomorrow morning... it honestly sounds like the whine that a T-case going out or bearing going out makes, except when standing still..... hoping its just the pump or exhaust vibrating but I will get a vid in the morning.

What is moving when sitting still? Nothing in the drive train with the exception of the engine and transmission.

Any trash in the tank?

[Outlaw]

What is moving when sitting still? Nothing in the drive train with the exception of the engine and transmission.

Any trash in the tank?

Well the videos didnt pick up the sound... it is resonating through the cab... I'm pretty sure after walking around and going through the inside that it is the pump... now I just need to know if it will cause any problems... it only does it after it warms up

[LizardRunner]

that is just fuel pump noise, you can isolate it with rubber sheeting around the tank straps and around the fuel pump mounting plate. a little rtv around that might reduce the heard hum in the cab.

[4.3LXJ]

If you isolate the tank, make sure you ground it.

[Outlaw]

that is just fuel pump noise, you can isolate it with rubber sheeting around the tank straps and around the fuel pump mounting plate. a little rtv around that might reduce the heard hum in the cab.

I will deffinately look into doing that thanks


If you isolate the tank, make sure you ground it.

And I will make sure its grounded dont want any "incidents" haha :smiley-gen165:

[LizardRunner]

I looked under Da Lizard to see how the tank is set up cause I don't have "abnormal" pump noise. found it has some "isolators" under the straps but maybe it's more just a "broken in" pump cause I only hear it when I first startup. the engine noise takes over from there. my tank is strapped (grounded). These probably are more for metal to metal rub than for noise isolation.