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ScoobySnacks S Hi. I've got a 2.5 174hp t5 camper (home conversion. It has sat for a while and now the alternator appears to have died. First off, is there an easy way to access the alternator to check if it really is the issue? (hopefully without having to take the front end to pieces. I hate removing trim) I've seen mention of a faulty gates coupling. She's only done a little over 80k, but has had a couple of longish idle periods, so it's this likely to be the issue? Is it possible to replace that without removing the alternator? Second option seems to be the voltage reg. Again, can that be replaced with the alt in situ? Final question. If I do have to remove the alt and replace it, I'd there a direct fit upgrade? Obviously the split charge circuit has the potential to draw a chunk more current than the normal charging system for a longer period, with the potential to wear out the alt more quickly. Where exactly is the fuse for the charging circuit? And can I access both ends of the alt +be to check if that might be the issue (I had rat get in to the van so am concerned about cable damage in general) Final final thing. Does anyone know of a good video or pictorial guide on how to work on the alternator? I'm at the talented amateur level, know my way round a spanner and have changed many a dodgy alt, but never one so thoroughly buried in the guts of a vehicle. Obviously I'll be putting a new serpentine belt on if I do start messing with the alt. I'd it like most, a good idea to replace the tensioner at the same time? Thanks for reading my ramble. I have to admit I've rather neglected the old girl for a while but is like to get her running sweetly so I can get her sold as I'm keen to get hold of a 4x4 before the winter. #1 · Mar 29, 2021 Hi. I've got a 2.5 174hp t5 camper (home conversion. It has sat for a while and now the alternator appears to have died. First off, is there an easy way to access the alternator to check if it really is the issue? (hopefully without having to take the front end to pieces. I hate removing trim) I've seen mention of a faulty gates coupling. She's only done a little over 80k, but has had a couple of longish idle periods, so it's this likely to be the issue? Is it possible to replace that without removing the alternator? Second option seems to be the voltage reg. Again, can that be replaced with the alt in situ? Final question. If I do have to remove the alt and replace it, I'd there a direct fit upgrade? Obviously the split charge circuit has the potential to draw a chunk more current than the normal charging system for a longer period, with the potential to wear out the alt more quickly. Where exactly is the fuse for the charging circuit? And can I access both ends of the alt +be to check if that might be the issue (I had rat get in to the van so am concerned about cable damage in general) Final final thing. Does anyone know of a good video or pictorial guide on how to work on the alternator? I'm at the talented amateur level, know my way round a spanner and have changed many a dodgy alt, but never one so thoroughly buried in the guts of a vehicle. Obviously I'll be putting a new serpentine belt on if I do start messing with the alt. I'd it like most, a good idea to replace the tensioner at the same time? Thanks for reading my ramble. I have to admit I've rather neglected the old girl for a while but is like to get her running sweetly so I can get her sold as I'm keen to get hold of a 4x4 before the winter. See less See more Sort by Oldest first Oldest first Newest first Most reactions #2 · Mar 29, 2021 (Edited) The first thing to do is put a volt meter across the battery terminals. It's not a complete test of an alternator but it is a guide. It should be roughly around 13.7 to just over 14 volts. When you switch on some loads on it shouldn't drop much. There isn't an easy way to get to the alternator on a 2.5 without some dismantling. It is possible to change the regulator without taking the front off but it is a bit involves taking the engine mounting and a few other bits off, unbolting and tilting the alternator. It does save a lot of time but you can't physically get the alternator out of the van this way so you may waste some time if the regulator turns out not to be the fault. There is no serpentine belt or tensioner on a 2.5. The alternator is driven directly from gears and has a toothed rubber (Gates) coupling that can strip teeth if the alternator seizes so that the gears don't get damaged. It is really hard to see but I think you can just about check that the Gates coupling is turning the alternator pulley. It's best to get the battery properly tested because that might be problem. 80k isn't much for a 2.5 alternator. As well as the Gates coupling, you could change the freewheel because if they seize they can ruin the alternator over time. You can change the freewheel by tilting the opposite end of the alternator down. I can't remember which fuses are linked to the charging system but there are probably more than one. Any of the fuses for the J519 onboard control unit (behind the dash) could cause a problem. If you want to have a go without removing the front, have a look at my little guide here.

ScoobySnacks said: ...so I can get her sold as I'm keen to get hold of a 4x4 before the winter. Wash your mouth out with soap! Click to expand...

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Alternator and AC freewheels and couplings 2.5 engines.pdf 9.6 MB Views: 163

#3 · Mar 29, 2021 I doubt you'll need to upgrade the alternator - I can't recall the rating but a split charge circuit shouldn't give the standard one much trouble in the overall scheme of things, unless your battery array is unusual. The alternator is fused at SA1 - it's a big fuse (around 200A)! #4 · Apr 5, 2021 Thanks. I'm just aware that the alternator is designed for a fairly short charging cycle after engine start. The split charge circuit can cause a significant load on the charging circuit for a much longer time, especially if you have a couple of batteries and have been running off them for a while. I know in some vehicles this can cause heating and extra wear on the alternator. I'll have a go at getting in to it and see if I can get it working. Thanks for the input.

0 Reply #5 · Apr 5, 2021 Re upgrading the alternator if you did go down that route. Years ago we often fitted higher rated alternators and converted old dynamo systems to alternator charging with no problems at all but I have seen two cases here where they fitted higher amperage alternators to 1.9's and both refused to charge afterwards. It could just have been two dodgy alternators but it could be that the J519 (onboard voltage supply unit) expects to see a certain output and gets confused if it's different. The J519 has a feature capable of switching consumers off if low battery voltage is detected. It might be that the J519 coding is adjusted for different rated alternators although I've never seen a reference to changing the coding for that reason. Insert Quotes Post Reply

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