Premium Member jeff400650 Posted May 14, 2023 Premium Member Share Posted May 14, 2023 I found the fuse under the seat blown. Replaced it, and it blew again. I can rotate the fan blades by pushing with a stick, but there is a bit of resistance, as in it does not rotate so freely that blowing on the fan would turn it. Is that normal? What would be the next easiest diagnostic step? Thanks. I have not been on the forum for a long time! Pistons or pedals, 2 wheels are where it's at... Link to comment Share on other sites More sharing options...
Wintersdark Posted May 15, 2023 Share Posted May 15, 2023 23 minutes ago, jeff400650 said: I found the fuse under the seat blown. Replaced it, and it blew again. I can rotate the fan blades by pushing with a stick, but there is a bit of resistance, as in it does not rotate so freely that blowing on the fan would turn it. Is that normal? What would be the next easiest diagnostic step? Thanks. I have not been on the forum for a long time! First, get a multimeter and ensure there's no short in the wiring. Disconnect the fan connector, check to see if there's continuity between the positive terminal of the wire and ground. I don't have my wiring diagram handy, so I can't say which that is, but with the wire disconnected from the fan, there should be continuity between one pin and ground (the ground wire) and not between the other pin (+12v) and ground. There will be some resistance when you turn it by hand, and it will typically kind of bounce into stepped positions - think as of if held in those positions by magnets, not just constant friction resistance. It should NOT feel grindy at all. Questions I'd have: Does the fuse blow as soon as you start the bike, or does it blow as soon as the fan would turn on? IIRC the fan turns on (stock) at 105C (whatever that is in F) so you could just start up the bike, let it warm up to where the fan would turn on. Does the fan move at all? Or does it just pop the fuse instantly? If it's instantly popping, it's almost certainly an electrical short given you can turn the fan by hand. 3 1 Link to comment Share on other sites More sharing options...
bwringer Posted May 15, 2023 Share Posted May 15, 2023 (edited) There's a "normal" amount of turning resistance as with any permanent magnet electric motor; as noted above, it's sort of "notchy" but you can easily turn it with a finger. It won't spin freely or with air blowing through it. One fairly common thing I've seen on other bikes is something keeping the fan from turning (for example, a warped shroud, or a stray stick or something similar). However, this would not blow the fuse until the fan tries to turns on. So I don't think the fan is the issue, unless we're misunderstanding you. If the fuse blows immediately before even turning on the fan, you've got a wiring issue somewhere in that circuit, perhaps a bad relay. Look for wiring damage; pinches, corrosion, marks from mouse teeth, etc. I believe the fan relay is the one hiding on the right side of the bike, next to and about in the middle of the top of the battery, under the seat plastic seat spacer. Pull that relay out and see if you still pop the fuse. If the fuse pops with no relay, then you have a short somewhere before the relay and after the fuse box (which is only a few inches away, but that red/black wire may travel through a few bundles). If the fuse doesn't pop when there's no relay, then a bad relay (internally shorted) may be the problem; check for continuity where there shouldn't be between the relay terminals. The Haynes manual has a procedure for checking the relay. Shake the relay next to your ear; if there's anything rattling around in there, or if you can see corrosion, burn marks, etc. it's definitely bad. Edited May 15, 2023 by bwringer 3 1 Link to comment Share on other sites More sharing options...
bwringer Posted May 15, 2023 Share Posted May 15, 2023 23 hours ago, Wintersdark said: Does the fuse blow as soon as you start the bike, or does it blow as soon as the fan would turn on? IIRC the fan turns on (stock) at 105C (whatever that is in F) so you could just start up the bike, let it warm up to where the fan would turn on. Does the fan move at all? Or does it just pop the fuse instantly? If it's instantly popping, it's almost certainly an electrical short given you can turn the fan by hand. Yeah, we really need to clarify exactly when the fuse blows. Does it pop right away when the key is on or the bike is started, or does it pop when the fan is supposed to run? 2 Link to comment Share on other sites More sharing options...
Supporting Member dazzler24 Posted May 16, 2023 Supporting Member Share Posted May 16, 2023 This -> " Yeah, we really need to clarify exactly when the fuse blows. Does it pop right away when the key is on or the bike is started, or does it pop when the fan is supposed to run?" Anyway, here's the info you need from the service manual to guide you through if still required. The circuit is straight forward in that it is Battery positive -> 15A fuse -> fan relay -> fan motor -> ground. As @bwringer has indicated - "..I believe the fan relay is the one hiding on the right side of the bike, next to and about in the middle of the top of the battery, under the seat plastic seat spacer. " It is the easiest one to get access to. If that proves OK then I'd be looking for that connector that goes to the fan (shown below as #96), pull it apart i.e. remove the fan from the circuit and re-test. Sounds like a bad relay - all things being equal and there are no shorts - but this info should be able to guide you through the process. Good luck and please let us know your findings. HTH. 🙂 Fuse , Relay and Fan... 4 Link to comment Share on other sites More sharing options...
Premium Member jeff400650 Posted May 17, 2023 Author Premium Member Share Posted May 17, 2023 You guys are great. Thanks for the sound reasoning and thorough responses. I hope to get back to trouble shooting this weekend. Need to get some more fuses. 2 Pistons or pedals, 2 wheels are where it's at... Link to comment Share on other sites More sharing options...
Premium Member jeff400650 Posted May 21, 2023 Author Premium Member Share Posted May 21, 2023 OK. I discovered that when I replaced the clutch cable (years ago), I routed it wrong and it was touching the ring that is connected to the fan blades, causing some resistance to them spinning freely. I corrected that, and let the bike warm to 205 degrees, at which point the fan turned on briefly, then stopped and blew the fuse. So should I assume I need a new fan? Pistons or pedals, 2 wheels are where it's at... Link to comment Share on other sites More sharing options...
Supporting Member dazzler24 Posted May 22, 2023 Supporting Member Share Posted May 22, 2023 It does sound like the fan is now faulty but to prove it you could use the test method for the fan as described above and included below BUT I would insert a 15A fuse in line from the battery positive to provide some safety. If the fuse blows then you have confirmed that the fault lies with the fan. 1 Link to comment Share on other sites More sharing options...
Premium Member jeff400650 Posted May 23, 2023 Author Premium Member Share Posted May 23, 2023 10-4. Thanks. Pistons or pedals, 2 wheels are where it's at... Link to comment Share on other sites More sharing options...
bwringer Posted May 28, 2023 Share Posted May 28, 2023 If this were in my garage, I'd use my DC amp clamp to see what the fan's current draw is. That's a somewhat rare meter, so as noted above, make sure you have a 15amp fuse in the circuit and try running the fan directly from the battery. If the fuse pops, then yup, the fan motor is damaged. 2 Link to comment Share on other sites More sharing options...
Premium Member jeff400650 Posted February 2 Author Premium Member Share Posted February 2 Thanks guys. I finally picked up a fan for $40.00 on eBay. Works great now. 2 1 Pistons or pedals, 2 wheels are where it's at... Link to comment Share on other sites More sharing options...
Supporting Member dazzler24 Posted February 2 Supporting Member Share Posted February 2 Good to see that you got it sorted Jeff. I have to ask... did you just get it sorted out recently or just following up late as your original post was from May last year!? Either way, always nice to get some feedback 👍😃 Link to comment Share on other sites More sharing options...
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