So I replaced my water pump along with secondary cam tensioners. The serpentine belt came off easily when I took the tension off the belt tensioner. however When trying to put it back with the tensioner fully retracted, the belt seems to be an inch too short and won't go over the pully's.

I have checked that the belt is going on the correct way, and the tensioner is all the way back ( clockwise with a 15mm wrench ) but it ain't going on. I am now wondering if the belt may be too short and was originally installed wrongly, but I can't see how.

can anyone tel me the belt length and part number , do Gates make one to fit ?

I think I could get the belt on by forcing it over the pully's by turning the main pully manually, but the tensioner would be very tight. it just doesn't seem right and am scratching my head here.

 

JagRepair.com - Jaguar Repair Information Resource

Here's a pic from Gus as to the layout. (above)

Below is a link to a Gates belt from a place called DriveWire that lists the length when searching on a 2001 XK8 Serpentine belt.

DriveWire

 

Make sure that the belt is completely over the edge lip of each pulley before trying to slip it on the belt tensioner pulley.

 

First, match up the new belt with the one you removed - if you are an 1" short - then you may have the wrong belt indeed - if they pretty much match up, then...Remove the belt tensioner assembly about 1" (to give you clearance) and you should be able to get the belt on all the pulleys - then re-tighten the belt tensioner assembly to proper torque spec.

 

I bought a new Pk7 2320 belt and it just fits, any shorter and it wouldn't go on. The original must have shrunk, I have heard they can if overheated. Also ordered new Dayco idler and tension pullies as these have seen better days.

With new water pump, thermostat and housing, new hoses, flushed and renewed coolant and the new belt the engine should be well cooled now. The fast fans still come on when sat in a long traffic jam on a hot day, just doing it's job I guess. They turn off when moving again so controller relays are ok.

 

I changed the belt, idler pulley, and tensioner pulley at 87,000 miles. The idler pulley bearing was beginning to make that scratchy harmonic noise. Off the car the wear was pretty obvious when compared to a new idler pulley.

I found it helpful to get an extra long breaker bar on the 15mm tensioner pulley bolt to give me easy leverage when loosening the tensioner pulley. Also I fitted the belt last on the alternator pulley (lower left facing the engine). This is the smallest pulley and needs the least amount of slack in the belt to slip over the edge of the pulley. JTIS indicates that the Alternator pulley is the first pulley to dismount the belt, so I figure it should be the last to mount. The key was getting enough slack by using an extra long bar when loosening the tensioner pulley.

 

Are you sure about clockwise. My manual states counter clockwise for removal and refitting. Just a thought.

 

All bolts are normal threads. So counterclockwise will remove everything. The one bolt with opposite threading is the single bolt mounting the tensioner pulley to the tensioner unit. which is a reverse thread. The JTIS warns not to turn this bolt clockwise because it will loosen the bolt. But Unless one is replacing only the pulley, and not the complete tensioner assy, there should be no reason to remove this bolt. To slacken the belt, this bolt is turned [pulled] counterclockwise facing the front of the engine.

Note the 15mm bolt mounting the pulley to the tensioner assy is not the 13mm bolt mounting the tensioner assy to the block. The 15mm is utilized to loosen the tensioner pulley [providing more slack in the belt] when the bolt is turned counter-clockwise.

If you are having trouble fitting the new belt onto the pulleys maybe you are not getting enough slack because the tensioner is not being pulled back to its limit. I used a two foot pipe over the socket wrench making it easy to extend the sprung tensioner to its counterclockwise limit, providing maximum extension of the belt.

If you are concerned about having a shorter belt length, then compare the old and new. The old does not stretch that much and the new one should be within a quarter inch of overall length. Put them both on a rod held in your bench vice and pull them out to compare lengths.