Timing chain noise

[Ian5700]

Recently a timing chain/dieseling noise has returned to my Explorer (it went away after it had an 00M12 kit fitted). I can't quite remember if the current noise is exactly like the previous one, as it was some time ago. The noise is louder when in gear than it is park, due to the higher idle; it also rattles under load 2500 rpm +.

Just wondering if having a new front tensioner fitted would solve this problem (it seems to be suggested that these be replaced every 75,000 miles), and or possibly the rear tensioner as i believe this to be the orginial one.

 

[2000StreetRod]

upper tensioners

The 00M12 kit included upper and lower intake gaskets sets, upper left front tensioner and O ring, oil return restrictor and associated plug. I believe the upper tensioners are spring loaded and oil pressure loaded. The spring pressure reduces chain slap when the oil pressure is low as in startup. The springs weaken with age and I think should be replaced every 75,000 miles. Well maintained tensioners will not reduce guide wear in my opinion. You should be able to isolate front chain rattle from rear chain rattle by listening with a hose or mechanic's stethoscope. It is fairly easy to replace the rear tensioner if you remove the wheel and inner fender flap.

 

[jcasey007]

getting paranoid about timing chain rattles

The amount of posts on this forum that discuss diagnosis, causes and fixes of the timing chains is making me think that mine is bound to fail anytime soon.

So are there now 3 constants in life ?

1. you are born
2. you will die
3. the timing chain will fail

Can anybody describe simply what the sound is like and when it usually happens?

Has anybody recorded the sound and loaded it on Utube? (that would be cool)

so that I can stop listening to my car ticking over when cold thinking "is that sound normal, is it a pully bearing" etc etc.

cheers

Jim

 

[Ian5700]

http://www.youtube.com/watch?v=jbHcNfevihk

There are a number of them on youtube, but that was the first one when i searched for 'ford explorer timing chain rattle'.

 

[JonC]

Jim, it sounds like light gravel being sloshed around in a steel pan. Happens more under load it seems as no doubt one side of the run is under tension and the other is flapping around in the guides.

 

[jcasey007]

The post on utube was a great clip and put my mind at rest that my chain and tensioners are not knackered !

The very slight noise I rear for about 2 mins following a cold start I tracked it down to a dry bearing in the alternator. All sorted following an overnight lube soak.

My EX is now up to 148K miles (44k in then last 10 months) so I'm right to be paranoid.

The dreaded LPG back fire returned out of the blue last week after 5 months of reliable running, and of course it gutted the airbox and blew off the vacume hoses even with the backfire valves fitted.

A quick check of the plug gaps confirmed that they had opened up to 50 thou over 18k miles. Regapping back to 35 thou has again returned the performance on GAS.