Finally got round to doing this. changed the spring tensioner and thought job done, but I can't get the belt on it now seems too tight. Anyone advise how I should fit the belt(pictures would be good) or what else may have gone wrong??
IIRC, on the 2.4 JTD the tensioner between the crank pulley and the aircon pump is also adjustable - on an eccentric bolt, I think - moving this might help, but I also seem to remember that you need a large spanner to move the sprung tensioner for the initial fitting. Sorry to be vague, but its a few years since I last worked on a 2.4 - did a 1.9 yesterday, but that's much simpler - just like a TS.
Yep, rgwn is right. The correct (Alfa) way is to use the spanner to rotate the spring loaded pulley against the spring so a locking pin can be used to lock it in the 'loose' position. You then 'slip' the belt on (temporarily removing the upper idler wheel gives you more slack). Final tensioning is by rotating the eccentric pulley at the front (special tool or an improvisation such as long nose pliers needed) so that the locking pin can easily slide out. Its a bit of a faff but worth doing right as over-tensioning the system will overload the various pulleys.....
I actually got the belt on by loosing the aircon pump, slipping the belt on and re-fitting the pump, however it was way to tight even with eccentric tensioner loose and the top idler out? does the spring loaded tensioner stay in the loose position when turned? I used the old belt so it's the right length.
This jobs easy when you know how.
1 Remove top idler pulley from above 13mm spanner.
2 Remove adjustable idler pulley from bellow 15mm spanner.
3 Remove crankshaft pulley torx bit.
4 Remove belt auto tensioner Allen key and 13mm socket.
The auto tensioner tends to seize it should be striped completely and lubricated and also carefully remove the bearing seals from the pulleys clean regrease reassemble and your Alfa will be good for another 4 years or 40000 miles ideally this should be done during the timing belt/ water pump change. DONT CUT CORNERS DO THE JOB RIGHT.
Another tip fit a Goodyear gatorback aux belt these are NASCAR approved and are the best of the best.
Is the belt you're trying to fit the right size? After heaving and straining and swearing a lot when fitting a new aux belt to my 10v I found that it was 10mm shorter than the original and that the various suppliers recommended belts which were +/- 10mm on the right size.
update. got the belt on by using a 32mm spanner on the spring tensioner. Found it easier to get at it from below. Belt is fairly tight and that's with the other tensioner as low as it can go? Is this because of the new spring tensioner and will it slacken a bit over time?
typed this before reading replies. Aye meant the crank pulley
dcbain I reckon your on the money