A place for more technical discussions. Please make sure you post in the correct section on the site, this way it keeps the site tidy AND ensures you get a more relevant answer.
Check what voltage you get when the engine is running, should be nearer to 14v. if its 12ish then the altenator needs replaced, 14ish then its the battery
J999 MNY, ULYSSES M18 VVT with ITB's Dyno tested at 130hp
One of the belts on my jimny has started to squeal mainly with these colder days coming in and it goes on for a while unless I drop the clutch for a short second or 2? Any advice would be appreciated
Check the condition of the belts and their tension is your first port of call. Pressing the clutch takes load off the engine hence less load on the belt/s.
As mentioned at the beginning of this thread (started in 2017) remove the belts and check the alternator by spinning it. It should be nice and free with no play. Then check the up and down and in and out movement when holding the pulley. The pulley itself needs a good inspection too checking for damage where the belt fits.If all smooth and free then the belts need a good inspection and ensure they are the correct ones.
For what it's worth , we went through this last year, it documented on here but a summaried version is , after 2 or 3 belts, a new alternator ,a new water pump , the only thing left was the bottom pulley. It turned out not to be separated but the grooves filled up with old rubber compacted so it looked fine but when wet there was not enough friction so it squealed and slipped heating the belt up so it became weak and snapped .
Fast forward to today and ...another jimny has started to squeal ...14.5 v at battery even with everything on , but the lights dull a bit and the radio switches channels occassionally!
I priced up alternator from local electrical factors £130 ..
It could be the bearings in alternator .
Reading back on this string and "have you checked the alternator bearings" has been voiced but no one has said "yes and this is what I found".
If good advice is given and ignored then what's the point?
Unfortunately this happens on other forums too. They dont understand or too selfish, that all fixes help us all and any info helps. It can be infuriating.
A good idea, our 2006 Jimny DOHC sometimes squeals it’s fan belts. I did check the Alternator bearings, even though it was only a couple of years old, the bearings were fine. I also checked the Water Pump, AC Compressor, Power Steering Pump and belt tensioner, all fine and spinning freely. The belts were so tight, they were more like guitar strings, but still the belts screamed in damp weather. It was difficult to find them, but a set of Raw-Edged belts (where the tensioning fabric strings go to the belts Vee edges), and no more belt screaming. I then slightly loosened the belts, as I don’t like to stress bearings, and still no screaming.
I will ask my mates where we got them from. I do remember it was on-line from a Belt / Transmission company, and not a Car Parts supplier. Armed with the belt length and width, it is straightforward to select Raw-Edge or the standard Wrapped belts. Apparently the Raw-Edge belts can transmit up to 30% more power than Wrapped, before they slip. It is this reason Car makers use Wrapped belts, as if bearings on an Alternator or Water Pump etc fail, the standard belt skips and squeals as a warning. I got so many different Jimny belt lengths on-line, I took the belts off, and measured them. Luckily their part numbers were still visible, to confirm the length and width.
