Have done a few bits to try and find out why the 2 red wires are getting hot and melting, I have fitted an m,p regulator which keeps the battery warning light working and spliced in the original connectors, Turn on ignition battery light is on then goes out when started which it didn’t before so fingers crossed that’s off the list. Next job was clean fuse box connectors checked all of them and were all in good shape and I m sure the last owner had cleaned them trying to sort the problem out also cleaned every connector/ terminal except headlight and the one behind the clocks will need to the take headlight out for them, Cleaned all earths. started up next and after 5 mins max smoke from the same two red wire fuse box wires so didn’t run it any further did this a couple of times and the same. Edit, just to add bike starts with a few squirts of easy start first. The battery that came with the bike is dead so took the one of my 748 which is 6 months old and last out on 748 was 3 weeks ago and haven’t had it on my optimate here are the reading I’ve found, I’m not clever with Electrics but have looked up testing for ohms. Battery fitted 12,31 Ignition turned on 11.60 Started,ticking over at 12,10 @ 1400 revs 1800 revs 12.55 3000 revs 12.75 These reading are with a new regulator, Next was test the stator with ohms Haynes manual has 0.2-0.4 My reading was 0.4 on both yellow wires. After running for around 10 mins to get a steady tick over switched off and test battery which read 12.28. Are my readings in line with what I should expect if ok then any other ideas for the smoke/ melting red wires or as mentioned could be a problem inside the loom, after short running times no melting of the blue 15a fuse or a broken one which I had before, all new but as i say after 10mins max of running. Also fitted new stater relay so now I don’t have to squeeze the old one to work.
Thought i would do the test again but with full charge. Ignition turned on 13.11 1800 revs 12.90 3000 revs 13.20 After this short run battery reading 12.62 These readings are with a new regulator. When reading previous posts about what the battery voltage margins are, mine seem under, Im thinking maybe the alternator but the reading from that was both wires 0.4 could it be faulty when running? I tried another idea. Switch on ignition with only the pump running and kept feeling the the two red wires, they got very hot within 3 minutes. Shorting out? Anyone got some ideas,
A wire getting hot is a sign of high resistance with the most likely candidate been the connectors having a bad contact. Also check carefully that any of that horrid green oxidisation hasn't crept under the insulation and compromised the wire from within.
Ive checked and cleaned all connectors in the fuse box, even with just the pump running its making them hot, the loom will be coming off, but trying to fix the problem-s before i take the bike part but might unclip the front section of the loom and cut the sleeving open for a good look first.
the lovely thing here is, that you will find it easily because circuit run is so small. If you can rule out all related connectors then next is wire itself as this can break down catastrophically with very little outward signs to begin with. First sign is that wire starts to look wriggly/snake-like, followed by darkening in colour, also see if wire is just as hot along whole length that you can get your hand on, or is it adjacent to a connector, is connector warped or discoloured? - I know impossible to determine the last one if black. Or.. we jump to the Elefant in the room which is the pump is becoming "sticky"/contains friction within. Also a severely blocked but still unpunctured "teabag" filter will cause pump to draw more current than it should. If you have renewed both then easy to rule out. Sometimes the tone/speed of the pump gives the game away.
Been in the shed this morning to find how a previous owner does things. Petrol cap off and all 8 grub screws came out easy next take the cap base out it came out with one finger pulling i thought to easy then noticed there was no fuel O ring just a bit of white plumbers tape and the rubber fuel cap O ring is perished, I could see the fuel hose had frayed underneath and even before i undone the jubilee clip, i squeezed the hose and the top part next to the clip fell apart how i managed to start the bike i never know, the teabag filter looks dirty. As you can notice there is no fuel filter. I would say the pump and wire connection block are not original, is the way the wires have been soldered ok for sitting in a petrol tank, There is no brand name on the pump i will be replacing it does anyone know what brand it might be. Inside the tank looks better then i thought As @Chris mentioned is the pump drawing to much power, because now I have taken a look and seen the split hose is the pump struggling/ going into overdrive / not pressurizing because of the split? Hope it can be the cause of the melting red wires in the fuse box
It was worth doing for the sake of the perished hose plus piece of mind in the future once re-assemble because this is one of the most neglected areas of the fuel system generally for me.
dont you just luv previous owners you think if they have done that what else have they done be sure to get the right grade of pipe or it will perish submersed in fuel due to ethenol content and enjoy replacing the tank cap with the correct o ring as its a bitch to do on the upside your on the way to a cracking bike to enjoy
I replaced hoses connections in Fuel tank, I believe you need "R10" spec hose for fully submersed. Cheers Gaz
Must say Moto rapido come up trumps with a very good service 24 hours later the parts are at my door. I didn’t know the in line filter was that big,
Ive always used the Mahle ones, they’re a bit smaller eg. https://www.ebay.co.uk/itm/Fuel-fil...2349624.m46890.l49286&mkrid=710-127635-2958-0
i think when i replaced the o ring on the filler neck i used a bit of rubber grease or silicone spray been a while think it was the grease just to ease it in and the rubber grease wont eat at the rubber like normal grease or wd 40 etc
Read a lot of threads saying putting the black tank seal back on was a nightmare, but to be honest it wasn't that bad. I manage to put the seal on bit by bit, when it was on I left it on there for a while which probably let it stretch and relax to the bigger diameter. It seemed to stay on there OK, as said previously, bit of red rubber grease to help assembly. Cheers Gaz
While you are in there make sure the drain from the ally piece(with the 8 m4 grub screws) to the bottom of the tank is clear. I have just done two that had blocked up(the 90 deg elbow) at the bottom of the tank and one was quite a fiddly job. The good news is the inside of your fuel tank looks decent!!
