Grumbling/grinding noise at high load, low rpm....up to around 15/1600 rpm

[jinjur]

Hey team,

Ok, i posted about this before as part of an essay style post but it was lost amid other posts. Rather than bumping that i thought i'd give it a thread of its own.

Firstly, car has been missing terribly of late and after a quick pull down the other night, i noted loads of flash over marks on one of the plugs, so i cleaned it down, made sure the plug lead was clean and dry and reassembled and that seems to be much better, no more misfires (but i have also lost the lovely bangs that used to happen, fark!)

Anyhoo....on to my main gripe and probably quite unrelated to the above.

When driving.....in ANY gear, if i labour the engine (i.e. low rpm, high load) for example, putting it into 3rd at low speed.....i can hear what i can only describe as a grumbling or grinding noise that seems to be from the driver side (belt side, i know ) of the engine.

No i don't drive like this all the time.....i am just trying to describe the scenario that causes it.

It can be heard in all of the gears....i.e....starting off in first.

The odd thing is that it disappears at the same rpm in every gear.....somewhere between 1 and 2k rpm. Id say around 15/1600.


I had read somewhere that the dephaser engages at 16 or 1800 rpm and was wondering, could this noise be coming from that? Perhaps its on its way out? Dephaser makes no noise at idle. none.

Another thought was that it might be coming from one or some of the pulleys or tensioners in the belt setup? Belt was done about 25K ago.....dephaser was not replaced.

Pinking? Could this be pinking? Its not the classic noise that i know.....

Finally, could this be the waterpump? Would be odd that it would disappear at that particular RPM.


Would really appreciate any and all thoughts

Cheers
J

 

[Odyssey172 Dan]

Sounds a bit of mystery
first thing i would say if it was dephaser it would normally rattle or start rattling as a friend of mine's 182 has started doing it,
but i wouldn't rule the dephaser out

second, is the clutch ok bite wise, not slipping etc

how old is the aux belt and water pump, i wouldn't say its the water pump but saying that you could check its turning ok by turning it by hand
I would first off give the aux belt plus water pump and other pulleys a check over then go from there

 

[jinjur]

Hey bud,

Yeah....dephaser doesn't make any "tractor" like noises at idle although there could possibly be a subtle noise there.....hard to hear when the sewing machine is running Was a bit miffed when Renault didnt do the dephaser when they were doing the belts but i was a bit ignorant to all of this back then and should have been a bit more informed before hand. My fault tbh.

Also, more conceringly....i don't know if they did the aux belt at the same time. Currently digging through receipts to see what parts are listed.

It could very well be that the aux belt wasnt changed at the same time.....which would suck.

I gather the water pump is the aux and main belt off job?

J

 

[Odyssey172 Dan]

All you have to do is take aux belt off and just turn the water pump pulley by hand to see if it turns smoothly, then that will rule it out.

 

[GrahamS]

jinjur

To change the water pump you just have to take the aux belt off. You may need to raise and lower the engine a bit to get it out because the chassis leg gets in the way.

Buy some loctite gasket remover to help with the job.

If you slowly rev your car whilst listening outside you will hear dephaser noise at about 1500-1800 rpm

 

[jinjur]

ok gents, thanks for that......ill try to make some time to pull the belt.....wont be this side of the weekend though.

tell me this.....if i were to pull the electrical connector to the dephaser solenoid.....would it cause any bad issues, even if driven just to test it?

This constant 1500/1600 rpm thing with the noise disappearing instantly is deifnitely making me want to rule out the dephaser too.

if i pull this connector and the dephaser solenoid doesn't activate, at least that would not point to that immediately

J

 

[Odyssey172 Dan]

ok gents, thanks for that......ill try to make some time to pull the belt.....wont be this side of the weekend though.

tell me this.....if i were to pull the electrical connector to the dephaser solenoid.....would it cause any bad issues, even if driven just to test it?

This constant 1500/1600 rpm thing with the noise disappearing instantly is deifnitely making me want to rule out the dephaser too.

if i pull this connector and the dephaser solenoid doesn't activate, at least that would not point to that immediately

J

It might cause some problems, i wouldn't really know about that but it would rule it out.