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Modern "No Start" issue solution

Discussion in 'Chat & Tech Info' started by GTM®, Jul 1, 2010.

  1. Rafael

    Rafael GT Reference

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    Okay, I'm picking this thread out of the many related threads to post my solution. It may not be a long lasting one but I'll find out.

    First off I haven't read all of the MPH solution thread. And I don't understand the solution diagram but I do understand that the voltage at the solenoid wire from the starter relay gets too low. My position is that the stock set up works most of the time on most bikes. My buddies to modern guzzis have NEVER had a starting problem. I'm guessing mine does cuz it started life in a barn with fancy horses.

    So, I've previously cleaned and lubed the starter, cleaned pertinent wire connectors with DeOxit.
    This worked for a quite while then recently started having the clicking no start problem again. It starts after a about 3 attempts. Checked the relatively new battery with load tester - it's okay. I checked the voltage at the connector to the solenoid and found it at 11.83 in start mode ( battery is at 12.8). So, I cut off the connector and put a gold plated one on and rechecked the voltage and found it improved to 11.93. Just enough to get it started on the first try without the clicking problem.

    This part has been mentioned above already, the solenoid wire is 20 ga.! Next time I have tank off for service I will bypass the 20 ga. with with a 16 ga. wire or add it in parallel with the existing one. This should allow a little more amperage to flow - I think.
     
  2. kiwi dave

    kiwi dave GT Reference

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    That's been my experience too. But when they fail there's only one surefire solution IMHO.

    It will, but will it be enough? The problem is the current for the solenoid from the starter relay is sourced from the ignition switch (and the cables from the battery to the switch and the switch to the starter relay). I can't accept the specifications of the ignition switch would cater for this large amount of current plus all the other loads it feeds. The fix described is simple and reliable, and will also increase the longevity of the ignition switch too.
     
  3. Rafael

    Rafael GT Reference

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    Right,... I'll measure the voltage at the relay next time I'm in there to see if there is a significant difference. Your right about the ignition switch, its a bigger deal to replace in a mod bike than the old tontis. When the gold connector doesn't do the trick any more work, then I'll try Pat's jumper from the battery or the MPH add on.

    I need a diagram in English to understand the MPH relay set up. My thought was to place a relay close to the solenoid juice by the + starter cable and triggered by the solenoid trigger wire from the relay. I think this should work based on the idea that low voltage fails to operate the solenoid and that its not the dash preventing a start because it sensed low voltage in the trigger wire.
     
  4. kiwi dave

    kiwi dave GT Reference

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    Not sure why you need an additional relay. Identify the starter relay, and cut the yellow wire feeding it. Then join a wire with a 15 amp inline fuse from the positive of the battery to the short yellow wire protruding from the relay. If you don't care for wire joins, then replace the wire completely on the relay base. I'm personally quite comfortable with a soldered or crimped wire join protected with heat shrink.

    The loose yellow wire from the loom can be used for any switched power functions, remembering the limitations of the current through the ignition switch. I used mine to power the Power Commander (or was it the AutoTune I can't remember which).
     
  5. Brian UK

    Brian UK GT Reference

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    I have done this mod on several Guzzis of various ages and sizes, and it has always cured the non start problem.
    Of course as the original issue is always intermittant, doing voltage readings may well be a red herring.
     
  6. dikman

    dikman Tuned and Synch'ed

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    While browsing the site I stumbled upon this thread. After reading, and re-reading, it I came to the conclusion that I should do it, if for no other reason that running the actual start current through the ignition switch seems like a pretty dumb idea. As pointed out, I doubt very much if the switch contacts are designed to handle that sort of current.

    I bought a copy of the workshop manual (2008 Breva) on CD, but the cct. diagram is virtually unreadable, so I downloaded Carl Allison's version, even though it's for a 2005. By a process of elimination I figured out which relay was which, but the colours of the start relay on my bike are slightly different to his drawing. Thinking that maybe a later version might be better, I downloaded all his drawings from 2005 on, but nothing matches the colours on my relay!

    The actual colours are Yellow and Orange/Yellow for the switched cct, and Brown and Red/Black for the relay coil. Has anyone else found this discrepancy with the colours?
     
  7. john zibell

    john zibell Moderator Staff Member GT di Razza Pura

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    The workshop manual can be downloaded from this site (downloads section) Also there is a generals service training manual that actually shows the physical location of the relays had you downloaded that (but again, actual machines may differ, mine was different, and a friends was by the book). As for the colors, Carl states the colors are from the Guzzi schematic, and Guzzi doesn't always hold true. I cheated and used the MPH gadget so colors weren't an issue on the 1100 Breva, but I used the other technique on a 750 Breva with no issues.
     
  8. dikman

    dikman Tuned and Synch'ed

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    Ok, no big deal if the colours vary, as long as I know it can happen (I worked in electronics - when I used to work :D ) so working without complete, and/or accurate, information is nothing new.

    John, the first thing I did was download all available info, but the manuals didn't cover the 2008 Breva, so I bought one and sent it to Todd to add to the collection. The only thing wrong with it is the cct. diagram - as I said, it's unreadable, so I'm grateful for Carl's excellent work (and this forum, of course!).
     
  9. john zibell

    john zibell Moderator Staff Member GT di Razza Pura

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    What is so different with the 2008 Breva?
     
  10. dikman

    dikman Tuned and Synch'ed

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    No idea, but I figured I may as well get one, just in case.

    Anyhow, here's a bit of a conundrum.....
    I replaced the yellow wire with a feed from my aux. fuse block, turned on the ignition, it goes through its start-up routine, I hit the starter and.....nothing.

    Hmmm. Bit odd. Then I notice that there's no neutral light on. Pull in the clutch, fiddle with the gear lever, yep, definitely in neutral and there's the light. Hit the starter, turns over, fires, runs for a couple of seconds (rough as guts) and stops. Turn it off and back on, no neutral light again. Huh? A bit more fiddling and I find that if I pull the clutch lever in the neutral light comes on but goes out when I release the clutch. Ok, back to square one.

    I removed my new battery feed, restored the old connection and this time everything is back to normal and it fires and runs fine.

    This has me puzzled. I've been poring over the cct diagram, but I'm blowed if I can see any link with the clutch switch - unless my bike is wired differently to Carl's drawings.

    Any ideas most welcome at this stage.
     
  11. john zibell

    john zibell Moderator Staff Member GT di Razza Pura

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    It is called a maintenance induced failure. What other connections did you have to restore? I'd look at what was done there.
     
  12. dikman

    dikman Tuned and Synch'ed

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    John, no other connections involved, the only wire I replaced was the yellow one (the one via the relay contacts). I did turn on the ignition with the relay removed, while trying to identify the wires, so I'm guessing that may have triggered the "maintenance failure", although why it only cleared when I put the original wire back doesn't make sense, particularly if that is only a battery feed.

    My first thought was that I had the wrong relay, but I don't think so. It's the small one against the frame, closest to the front of the bike. It also had two wires that matched the colours on Carl's cct (including the yellow via the contacts), none of the other relays came close in that regard.

    I'm not overly worried about it, just very curious.
     
  13. john zibell

    john zibell Moderator Staff Member GT di Razza Pura

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    The guys at the factory don't always put the relays where they are suppose to. Disconnect the solenoid (at the starter) and make sure the wire doesn't ground and touch the relay when you press the starter button. You should feel it click.
     
  14. Rafael

    Rafael GT Reference

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    All right, went ahead an did a version of the mod. The gold plated connector only helped for about a month.

    I already had a 30 amp relay set up for aftermarket heated grips, so I figured that this relay can serve another function. I stead of connecting directly to the battery, I connected to the power output of the relay which is connected to the battery. Disconnected the Yellow (B11) wire at the relay and plugged in a new wire from the heated grip relay.

    I don't think the voltage is a red herring - if voltage is a factor in amperage then why wouldn't a lower voltage be a cause for inadequate amperage at the solenoid.

    Not sure if this is the MPH solution - maybe maybe not, in any case with a shorter run from the batter there's less resistance.
     
  15. dikman

    dikman Tuned and Synch'ed

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    I've resurrected this because my recent misadventure sort-of fits in with some of this (I think, although I'm still a wee bit perplexed). The bike's been fine until now - I rode to the library, came out, turned on ignition, it went through the startup routine, I hit the starter and - nothing! Tried again, same thing. After the panic had dissipated, I checked the fuses and the "B" fuse in the secondary fuse box had blown (this feeds the parking light, rear light and provides the power to the start relay contacts to operate the starter solenoid, hence no starter). I replaced with a spare 15A and away we go. Until I stopped further down the road for petrol and wouldn't start again!! I replaced the fuse, but this time it still wouldn't start (fuse had blown straight away). I stuck in a spare 25A fuse (this was clear so I could watch it as I turned on the ignition) - instant poof! At this point I rang my wife to pick me up so I could get the cct diagram and some test gear - she was NOT happy!!

    I figured there had to be a solid short cct. somewhere, but testing with a multimeter couldn't find any problems, so I put the meter in place of the fuse, reading amps, and cranked it and away it went. I replaced the fuse and it was fine for a couple of days, until it happened again but at least this time I was at home. First thing I did was hook the meter in place of the fuse and cranked it. With ignition on it was drawing about 700 mA, which would have been the lights, and when I hit the starter it jumped to about 4A, which would have been the starter solenoid, and then dropped back again when it was running. I did this a few times and then suddenly instead of 4A it jumped briefly to 13A! This surge would probably account for the fuse blowing, as it may very well have peaked higher. But as to what caused it......

    End result, I checked all the connectors, including pulling the starter, but could find nothing wrong. I have an auxiliary fuse panel fitted, currently only being used for my Stebel air horn and it's located next to the battery so is very close to the start relay. I disconnected the main battery feed wire to the start relay, as mentioned earlier in this thread, and replaced it with a 15A feed from the aux. fuse panel. I figured that at the very least this will isolate the start cct from the lights, so I'll have a better idea where to look if something blows again.

    This doesn't make a lot of sense to me, as the cct involving that particular fuse is very simple, and a short that could blow a 25A fuse should be easy to find, nor would I expect it to come and go like it has.

    Oh well, at least I'm starting to understand the wiring of the wee beastie a bit better!!
     
  16. john zibell

    john zibell Moderator Staff Member GT di Razza Pura

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    dikman,

    Did you ascertain the voltage drop at the starter relay? That is the available voltage on the power side of the relay vs the actual battery voltage? Anyway, the modification you made should take care of the situation.
     
  17. dikman

    dikman Tuned and Synch'ed

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    John, I hope you're right! I'm still perplexed as to how just turning on the ignition can sometimes cause this fuse to suddenly blow - but not always. And why it's suddenly started doing this after all this time. Anyhow, we'll see what happens.
     
  18. dikman

    dikman Tuned and Synch'ed

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    Well, I've been out shopping today, so quite a bit of stopping and re-starting and it didn't miss a beat. I'm not completely happy about all this because what was happening doesn't make a lot of sense, but re-wiring the start cct, as per this mod, certainly won't do any harm.

    Time will tell.
     
  19. dikman

    dikman Tuned and Synch'ed

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    Just got back to this thread (I'm taking up black powder shooting, so that has been a major distraction from my usual interests) and, lacking any other solid evidence as to the cause, your idea is as good as any, Tony. I'm pretty sure that the solenoid seemed ok, but it looks like I'll be pulling it out again to make sure!

    There can't be too much wrong, as the bike has been running fine. But I need to know!!!
     
  20. Brian UK

    Brian UK GT Reference

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    Anyone know the function of the starter maintenance relay as designated in Carl's diagrams for the 8 valve bikes?
    Does this affect the normal fix for the start problem?
     

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