How do you replace the serpentine belt?

[02-SR5]

Looking at the front of the engine, I cannot identify any adjustment to release the belt for replacement.

It is not due, but I want to have a spare for that just in case moment. I would rather find out now and not later when it is to late.

[DaveXT]

There should be a spring loaded idler pulley, you simply put a suitable socket and a long bar. Haven't really looked at mine but you may need 3 hands!

[dimmo]

Looking at the front of the engine, I cannot identify any adjustment to release the belt for replacement.

It is not due, but I want to have a spare for that just in case moment. I would rather find out now and not later when it is to late.

not sure if these pics are any help. There's a lot more info in the manual.
hi-res versions of these pics are available too if you want.

[900canoes]

Looking at the front of the engine, I cannot identify any adjustment to release the belt for replacement.

It is not due, but I want to have a spare for that just in case moment. I would rather find out now and not later when it is to late.

As Dave wrote; Put a socket on the bolt in the tensioner pulley and turn it clockwise (tighten) direction. This will overcome the tensioner spring and move the pulley away from the belt (nothing to undo). There is a hole where you can insert an allen key that acts as a holding tool, so you can take your socket out of the way while you free up your other three hands to remove the belt.

If you dont have the workshop manual I can put a pic up for you.

[Lakey]

So just looking at replacing the serpentine belt and A/C v-belt. Just looking at the tension figures. Serpentine belt has the auto tensioner so it's not such an issue unless the tensioner isn't working. V-belt on previous cars I've always just given it a bit of a push in with a finger to see if it was loose or not.

The manual for this thing however talks about using tension gauges, or measuring deflection or a sonic screwdriver (okay it's actually a belt tension meter). The deflection method requires a 100N pressure to measure the deflection. I'm assuming this would be using a 'belt tension gauge' such as Daytona DTENCM Universal Cam Belt Tension Gauge (sydneytools.com.au). Issue is the figures quoted for the deflection at 100N (Newtons) seems to be way outside the range of anything else I've seen on line.

Anyone else actually used one of these devices. The gauge looks similar to the 'Tension Gauge' that Mitsubishi have in the manual for the other method but it has values in N again way outside anything quoted elsewhere, I'm assuming that the type of gauge Mitsu talk of is different to that used to measure deflection.

Anyone have any experience with any of these?

Cheers
G

[old Jack]

Hi Lakey,

100N is only 10kg force and this can easily be applied by hand/thumb. If you get a bathroom scale and push down with your thumb then you can get a feel for how much 10kg of force feels like.
For an AC belt it is better to be slightly under the correct tension than over the tension.

Specification is 7mm to 8mm deflection with 100N of force applied on the belt, midway between the compressor and tensioner pulleys.

http://faq.out-club.ru/download/pajero_sport_2008/maintenance/Service_Manual_2009_2011/img/11/AC506004AB01ENG.pdf

OJ.

[Lakey]

Hi Lakey,

100N is only 10kg force and this can easily be applied by hand/thumb. If you get a bathroom scale and push down with your thumb then you can get a feel for how much 10kg of force feels like.
For an AC belt it is better to be slightly under the correct tension than over the tension.

Specification is 7mm to 8mm deflection with 100N of force applied on the belt, midway between the compressor and tensioner pulleys.

http://faq.out-club.ru/download/pajero_sport_2008/maintenance/Service_Manual_2009_2011/img/11/AC506004AB01ENG.pdf

OJ.

Thanks OJ, hoped you'd come through again! 10kg is much more familiar and I can check that with a spring balance if I don't trust my thumb.

Cheers
G

[itsamitsi]

When a timing belt gets done do the serpentines while you're there. Have to take them off anyway. They last way longer than that so no need to carry a spare. Main belt is auto adjusting so no need for anything there, A/C tighten it up so there is a little deflection on a new belt as they strech anyway. Used belt stick to a little more deflection as it won't reaaly stretch further.

[Kingbrown]

Whilst remembering to have the aircon idler pulley's axial mounting bolt LOOSE when playing with the adjustment bolt.
Only tighten the mounting bolt after adjustment has been completed.

Mitsubishi talk of marking the direction of belts and installing them in the original orientation if they are to be reused. Obviously a belt will work in either direction but there must be a good reason for Mitsubishi to specifically mention this.

[old Jack]

Whilst remembering to have the aircon idler pulley's axial mounting bolt LOOSE when playing with the adjustment bolt.
Only tighten the mounting bolt after adjustment has been completed.

Mitsubishi talk of marking the direction of belts and installing them in the original orientation if they are to be reused. Obviously a belt will work in either direction but there must be a good reason for Mitsubishi to specifically mention this.

All belts be they timing, serpentine and even V belts should be run the the direction of rotation as marked on the belt when new, but once fitted, if then removed, they should be refitted so they rotate in the direction that they have been running in, even if it is incorrect!

https://www.gatestechzone.com/en/news/2017-03-direction-of-belt-rotation

OJ.

[itsamitsi]

Mitsubishi talk of marking the direction of belts and installing them in the original orientation if they are to be reused.

I have seen Toyota and general mechanics do this so there must be something in it...

[old Jack]

I have seen Toyota and general mechanics do this so there must be something in it...

It is called good engineering practice, unfortunately it is like common sense, not much of it around now days.
Now days it is all about the speed at which a job can be done and the amount of shortcuts you can take, but quite often at the expense of doing the job correctly.

OJ.

[Lakey]

Thanks guys, lots of good points there!