nzvette

Hi guys,
Just started getting a rumbling noise which sounds like its coming from the alternator. Doesnt start until the engines been going for at least 5 minutes. Been to 3 workshops here in New Zealand, one thought it was the cracked serpentine belt. Changed that, no difference. Another thinks it is the alternator ( sounds like bearing rumble) another thinks it could be the steering pump as the rumble changes as you turn steering wheel and the pulley has a bit of sideways movement. Or maybe the harmonic balancer, as it has a slight wobble, tho I can't see how that would make a rumbling sound after 5 minutes. the belts do not chirp or squeak. Anybody got any suggestions? Thanks in advance for any help.

RC000E

One of your cooling fans out of balance? see if the sound is consistent with one of the fans coming on.

nzvette

Thanks. I will check

robertmc1958@gmail.c

Take a stethoscope and check each component while the engine is running and making the noise. Be very careful while doing this to avoid belt. You can also use a large screwdriver.

Black 02

Idler pulley?

feeder82

if the balance has a wobble its probably ready to come apart, the rubber is failing. lots of posts in tech about harmonic balancer failures

dadaroo

Whether a damper wobble is causing your noise, you need to address that problem before you have bigger problems.

RC000E

I had a similar issue, and it sounded much like a "rumble" from inside the car. I had replaced a bad fan with an aftermarket unit and one of the fan blades broke causing an unbalanced situation...it sounded quite noticeable in the cabin.

Let me know what you find.

James2002z06

Mine was the a/c compressor .....

nzvette

Hi guys, still having problems working out what is causing the noise. It is like a rumbling rattling bearing type noise. I have replaced the serpentine belt and the alternator has had new bearings. I think it is the power steering pump even tho one workshop reckons they dont make that sort of noise, but the workshop i went to today thinks it is. The noise practically goes away as you move the steering wheel, so Im pretty sure it is the problem.
Noise only starts when the engine has been running for 5 to 10 minutes.
Does anyone know if there is a filter somewhere in the pump that might get blocked?

jim993

I am not aware of a filter in the power stering system.

One more thing to check, after the rumble starts, is to then remove the serpentine belt and give the water pump a spin by hand. It should be more or less silent.

I had a rumble that I could not diagnose with a stethescope, but was revealed to be the water pump through the above proceedure.

Oh 2 Fun

There are many choices where this sound could be coming from.

Can I assume you are not losing coolant? A bad water pump can rumble.

There are also idler/tensioner pulleys, upper and lower that could make this noise.

You probably should try the stethescope thing or a short piece of garden hose to the ear and listen around.....be careful though!