Wh Grand Cherokee Common Faults And Issues

[Bloke]

I use LiquiMoly Clean & Boost every 2nd tank. At the 30ml/10L or (240ml/Tank), the CRD flies. It cleans and lubricates the fuel system and provides cleaner burning. I might try that decarboniser. Water injection would be a great alternative as a permanent solution. Lower EGT's as well.

[Dippas]

Ok the plot thickens.......

I just went outside to take another look at her and the noise was not there while idling for about 5 mins then it started slowly slap......(5-10sec) slap, slap..... Etc.

So I grabbed my 17mm socket and ratchet and placed a small amount of pressure on the serpentine belt tensioner to loosen the belt and voilà noise gone.... Then letting go of the belt it comes back, after doing this a few times to verify it stops all together...... I cannot replicate it. So I stop the engine and restart a minute or 2 later and its back..... So repeat the loosening of the belt and the noise again goes away.....

I'm wondering if it could now be the vibration dampener or another pulley?? The noise when I hear it sounds like its coming from the damper area.....

( I still will be changing the oil filter tomorrow just to be sure )

Anyone heard of this happening before?? Cheers.

[Clarky]

Link to Pulley tread
http://www.ausjeepoffroad.com/forum/...ghlight=pulley

Originally Posted by Clarky

Part numbers are

Idler tensioner. 1 required
EP257 Flat Steel 17mmID 65mmOD 29mmW for

Belt idlers. 2 required
EP251 Flat Steel 17mmID 54mmOD 30mmW

ALTERNATOR OVERRUNNING PULLEY
OAP168 17mmID 50mmOD 49.3mmW 33 Tooth Spline 7 Rib (WJ are OAP007, 6 Rib)
Tool needed to remove Alternator pulley OAPT33

Handy links
http://m.dayco.com.au/BuyersGuide.aspx
http://www.dayco.com.au/products.asp...3kJW+mShDDQc8=
http://www.dayco.com.au/products.asp...WnSJL8ux2ev/I=
http://m.dayco.com.au/ProductItems.aspx?P=18043191
http://www.eziautoparts.com.au/pdf/N...ne_Pulleys.pdf

[Bloke]

Yep, confirmed noise coming from the belt tensioner. I have been suspecting it being the rattle I get. Some cold starts there is a flattering sound and when I look at the belt while engine is running, the tensioner has excessive movement. My belt needs replacing anyway (likely stretched) but might have a slack tensioner as well. While the belt is off I will check all pulleys for tolerances. The front edge of my belt is worn which shows signs of misalignment - or caused from the flapping around of the tensioner.

[Dippas]

Originally Posted by Clarky

Link to Pulley tread
http://www.ausjeepoffroad.com/forum/...ghlight=pulley

Thanks again Clarky!!

So do you think its the pulley's?? I have replaced the tensioner pulley (not the whole tensioner) a few months ago and the idlers are the newer steel type (not sure how old) and I have not done the alternator pulley at all.

I did notice that the harmonic balancer/damper seems to wobble a bit when running, about 1-2mm in a vertical direction when looking at the balancer front on (if that make sense) there doesn't seem to be much in/out movement from the balancer.

Could it be this movement that is causing the noise or is it more likely to be the idlers?

Its just weird that the noise goes away by only slightly reducing the tension off the belt.

I will try the idlers first and see if that helps! Cheers again!!

[Bloke]

Originally Posted by Dippas

I have replaced the tensioner pulley (not the whole tensioner) a few months ago and the idlers are the newer steel type (not sure how old) and I have not done the alternator pulley at all.

I did notice that the harmonic balancer/damper seems to wobble a bit when running, about 1-2mm in a vertical direction when looking at the balancer front on (if that make sense) there doesn't seem to be much in/out movement from the balancer.

Could it be this movement that is causing the noise or is it more likely to be the idlers?

Its just weird that the noise goes away by only slightly reducing the tension off the belt.

I will try the idlers first and see if that helps

I noticed the same from my harmonic balancer. They can become delaminated. My fathers Camry had an aircon pump bearing worn and chewed the belt up over time. With the tensioner, it's the springloaded arm (in particular the spring) that is the maintaining force for tension. Like mine, if the spring slackens or the belt stretches there is not enough preload against the spring and it will vibrate. The only question is, do I fork out $250 for a whole kit or $60 for the belt. I need to replace the O'ring in the charge air line - pre silencer as oil has been also dripping on the belt which can't be good for it. But eitherway, I will be removing it when I change the belt so I can get better access to the pullies to check everything. I have just reached 170,000klms and a lot of original parts don't last too much longer. I recall mums Falcon around the same mileage. We were under that car for a while changing out bearings, joints bushes, pullies etc.

[Clarky]

If you are going to the trouble of changing the belt then do the pulleys. I did all but the alternator pulley (was sent the wrong one at the time) & it sounded so much quieter when finished.

Mine had a whirring noise not a tick.