Hey,
I've got 72,000 miles on my original JCW timing belt on my 03' Cooper S JCW. When should I replace it? thanks, Fred.

 

No timing belt on the MINI. Are you referring to the drive belt for the supercharger, alternator, and AC compressor? If so its been a tad overdue

 

yep, the serpentine belt is what I'm refering to.

 

you are way overdue...

Go ahead and replace the belt tensioner as well.

 

From what I've been told the replacement schedule for the JCW belt is at the service Inspections, 1 or 2, which are approximately every 30,000 miles.
The plugs are recommended to be changed at every Inspection 2 or approximately 60,000 miles.

Hope this helps...

 

Sorry to hijack, but ive read allot on different sizes belts for different sized pulls. I understand the JCW is in hte middle of a stock and 15% from a bunch of reading.
What is the right size belt for JCW pully? On wmw the jcw belt says it fits stock r53 and jcw.

 

The following part numbers, for the Ribbed V-Belt, are from Real OEM:

Stock pully= 11287520199
JCW pully= 11287545120

Sorrry but I don't know any of the aftermarket part numbers.

Hope this helps...

 

No offense, but if youre mixing up the timing belt and serpentine belt,
You might not need to be changing any belts...
But you have plenty of time.. I didnt change mine until like 85k or 86k

 

i would say Change it!
better safe than sorry... your engine wont be damaged should your serpentine belt go out, but your Belt tensioner Will! those things overstretch and explode (not really) and are worthless afterwards. Thats Another $130 on top of a new belt!

The belts themselves are like, $30? super cheap... and if your "wirey" enough, you can do it yourself. Ive seen other threads where people "make" their own pulley tool: one guy just used a crow bar and a large socket for leverage!

 

If you are refering to the SC belt...the one that also drives the alternator, a/c, and waterpump (by way og the sc) you are way overdue...by miles, and several years...and it can cause $$ dammage if the belt fails...not to mention a tow. A belt is barely a $30 item...takes about an hour to install.

 

By almost 2x the miles and 3x the years....edit-my dealer was recomending 45k or 3 years.
Tennsioner may be a good proactive change, but they are good till they fail, so if money is tight, you might chance it, but if the car is on a lift, the extra $150 to do the tensioner can be $$ well spent, cause it may save you issues later, including a second trip to a garage and redoing much of the same labour.

For timing mini uses a chain internally....unlike many asian makes that have belts that must be done at about 110k intervals.

 

The belt drives the water pump...once the belt breaks, they overheat QUICKLY, the temp gauge will skyrocket almost immediately. Engine damage will occur if one doesn't shut of the car in a timly manner...aka immediately.

 

Also when the belt snaps (rather than shreads), the tensioner can whip back and dammage not only itself, but the crank pulley....$$$$. So to save $30 in parts you might spend $600 in parts, plus labour....and if you did't pull over fast enough and it overheats, add a headgasket...and maybe a cracked head....

 

The Mini-recommended replacement interval for the MCS "engine accessory belt" (the main belt that drives the supercharger/water-pump, alternator, and A/C compressor) is 60K miles. (If the JCW has a shorter recommended interval, I'm not aware of it.)

The engine uses an internal timing chain to drive the valve gear with no replacement schedule. So if the accessory belt breaks, there is no consequence to the engine's valve gear. You will, at a minimum, lose supercharger boost, alternator power, and engine cooling, so this is essentially a disabling problem and you certainly want to stop the car and not try and drive it further. I've seen mixed reports of whether a routine belt breakage with a normal precautionary shutdown causes further damage.

- Mark