'85 VF500 interceptor no spark

Discussion in '1st & 2nd Generation 1983-1989' started by John painter, Apr 15, 2018.

  1. jeremyr62

    jeremyr62 New Member

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    Not much point calling everything made in China garbage these days. Virtually everything is made there including 1000 dollar IPhones. Besides, my cheap ultrasonic cleaner has held up pretty well.
     
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  2. John painter

    John painter New Member

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    I'm still not certain I understand how that works, since the pump runs when I press the starter (I can hear it and feel it), when I flick the off switch to off, it turns the pump off, is that how it primes the carbs. I'm too newbie, but I appreciate your patience in trying to explain this.

    So what I ended up doing was detaching the fuel line from the pump to the carb, pouring gas in the line with a little funnel I had, and blowing it into the carbs, I filed the line with gas back to the filter. I then used the same funnel and poured some gas in it to prime the pump, though I could hear and feel it pumping when I pressed the starter switch, it did not seem to move any gas. I replaced the other fuel filer with a clear one so I can see whats inside.

    Using that method to prime the carbs, and I think the fuel pump is now pushing fuel, I can get the bike to start, however it barely idles, maybe 500rpm and dies with any throttle. :confused:

    I'm a little suspicious not all the cylinders are firing, that I may not have screwed the ignition wires into the coils well and I just don't have spark. I'll double check that in the morning.

    What else am I forgetting? I appreciate the guidance, even if I don't "get it" at the time. Thank you! :Yo:
     
  3. John painter

    John painter New Member

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    Thank you.

    Gas is now coming out of the carb that was dry.

    I removed and cleaned the needle, seat and the itty bitty filter. Wow, they are small.

    Fuel tank flushed and innards of petcock look ok, I did not see any holes in the diaphragm.

    I did not replace the bowl gaskets, or intake boots (yet) to the best I can tell, nothing is leaking air or fuel - though that's probably a matter of time. And if I have to take those carbs out again, I will certainly replace those things. Carbs were tricky getting back in, and took time wiggling here and there but eventually went in using the techniques I've read from yours and others posts. Thank you.

    I was only able to see light through the jet after putting wire through it, though I used copper since I was freaked about using anything harder, afraid I might gouge it somehow. I was able to visually inspect everything pretty close with a magnifying camera I have for my iPhone, so I was able to see the walls inside the needles, they were clean.

    I have no idea why the bike ran previously when the carbs were so horrible, so I'm a bit baffled now that they are clean why the bike can barely idle. I got it to idle after blowing gas through the gas line into the carbs, then putting gas into the fuel pump and reattaching. It idles, sort of.

    Thank you for the suggestions, I may yet take you up on your offer if I can't get this right.
     
    Last edited: May 19, 2018
  4. John painter

    John painter New Member

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    I will probably get an ultrasonic cleaner from my good friends a HF. :nelson:

    Though I've been thinking about that for my old Johnson outboard's carb that needs a cleaning (I do a little lobstering summers), it's a constant battle with sea water and salt air at my cottage to keep that outboard running well, but it's older than the VF and has really never let me down.
     
  5. jeremyr62

    jeremyr62 New Member

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    Messing with carbs takes patience. Running on three is not uncommon after a carb clean, and then it will start to run on four. Don't ask me why. One thing to invest in if they are not new are a set of plugs. You need to eliminate all the things that could give problems.
     
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  6. John painter

    John painter New Member

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    Thank you, yes I had already put new plugs in. I already had them and a socket from my XR600.

    I came to the conclusion that the the fuel pump was not pumping (I had replaced the replaced fuel filter with a clear one so I could always see whats in there) and I just wasn't seeing fuel movement.

    I had another pump which is large but pushed at around 3psi so I put it in and it fired up. I then did a quick clean up of the innards of the old pump and put it back in, and it's pushing fuel now! :Bounce:

    I rode it around the block to see what it was like, and it's frigging nuts... In a good way! It feels bigger than a 500. I've ridden (never owned) a Ninja 500R and I didn't really like it, it was a good bike and all but I didn't think it was anything special. This VF, good Lord.

    Getting it to idle below 2000 without choke is my new challenge. I have to wonder if there's some bit of crap somewhere in a jet though I examined and cleaned and reexamined everything before putting back, or after years of people messing with the carbs if the pilots screws are all way off. There are no plugs in front of the pilot screws so I'm guessing they have been messed with. I found the settings for them on pg 155 of the Clymers but, the idle adjust knob doesn't really seem to do much turned in or out. It is connected.

    How do I have to hold my jaw to try and adjust the pilot screws or can I without getting it to idle first? Thank you and others for some wonderful information and areas to focus on!

     
  7. jeremyr62

    jeremyr62 New Member

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    I have a 1985 VF500 which has a fuel pump but I just disconnected it and fed the carbs with gravity only. Works fine even at full throttle. So you could try that too. The pilot screws should be set at 2 or 2.5 turns out. The black idle adjuster knob definitely should increase the idle as you turn it in (clockwise). You might need to blip the throttle to get the linkages to settle down as you do it.
     
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  8. John painter

    John painter New Member

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    That's not something I saw in the Clymers about the pilot screws, thanks I'll dive into that tomorrow or sometime later this week!!

    One last set of photos of the jets from the carb cleaning. I totally understand why this bike needs a proper carb cleaning now, and for anyone else considering it it is not too difficult but does take time and patience.

    I still have no idea how the bike ran with the jets so totally clogged like this. Again thanks to the people on this forum for the excellent information!

    IMG_1342.JPG
    IMG_1343.JPG
    IMG_1344.JPG
     
  9. John painter

    John painter New Member

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    Wow, what a difference from the day I rescued it from the woodpile!

    Sixth gear, around 8000rpm - wow what a nice little surprise up there, really moves.

    I think this bike is worth keeping.

    vf1.jpg

    vf2.jpg
     
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  10. Diving Pete

    Diving Pete Member

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    another saved - excellent job..
     
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  11. John painter

    John painter New Member

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    And this is what a spedo gear looks like after 30 years or so...:Whoo:

    gear.JPG

    New one is in and working as it should.

    I also wanted to provide some feedback on the Duro HF918 tires I put on the front and back, Duro makes the correct VF sized tires, while I can't say they are excellent, for the price they are great. Much better handling than the oversize tires the previous own had on the bike. They corner well, and I don't feel like I'm driving an old truck without power steering going around tight corners. So far I'm riding super slow and easy (mostly), and I have not ridden on wet roads yet so I don't know how they will behave in those conditions. I also haven't had them long enough to know how many miles they'll go, but so far they still look like the day I got them in the mail. So for $131.98 for both tires at Bike Bandit, I'm happy with them.
    t1.JPG

    t2.JPG

    gas.JPG
     
    Last edited: Jun 2, 2018
  12. John painter

    John painter New Member

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    Yet another vexing mystery. I know this should not happen, but it did.

    Bike was running very good, so I decided to change oil and filter. Now it runs like crap. By that I mean it will not idle without the choke all the way on and it has no power. Oil light comes on when I turn the key on, and goes out when the bike runs. Interestingly I get a whir from the starter quite a bit before it catches. And tachometer isn't working.

    The only thing I did, and touched was the drain plug when I drained the oil, and the oil filter when I removed it. When I first put the filter in (I put some oil in it) and started it bike the tachometer jumped around a lot. I rode it around the block it had power then, so I garargeed it and went back yesterday and it's like a different bike. Totally stumped.

    I used Mobile synthetic 10-40, 2.6qt and the only thing I can think of is maybe it's so thin, and not as viscus as regular oil that it just is having a hard time getting to pressure until the bike gets used to it? I know the bike is temperamental so this is the only straw at the moment can grasp, but I've never experienced anything like this in hundreds of oil changes on bikes over the years.

    I'm stumped.

    I did some internet searching and have seen some posts around the web on similar things happening after an oil change but mechanically I just don't understand why this would happen. Much less how to correct it. Suggestions?
    :(
     
  13. squirrelman

    squirrelman Member

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    jumping tach suggests a bad electrical connection to the coil that drives it or a bad ground.

    check the battery voltage and charging system output.

    an oil change was NOT responsible for the problems, and you did well to pre-fill oil filter ~! after an oil change i always crank over the engine on the starter (with run switch off) until after the oil pressure light blinks off.

    BTW, if you are using a Unifilter for air, know that they're dreck and fall into pieces after a short time. don't use ! petrol fumes and the filter oil destroy them.

    dija pack grease around the new speedo drive ?
     
    Last edited: Jun 13, 2018
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  14. John painter

    John painter New Member

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    Good idea, thanks!

    I know that an oil change can't do this, but it's just so strange that this happened after an oil change, I did nothing other than change the oil and filter.

    I have a new Honda air filter and No Toil filter oil (the Uni sticker is just a sticker), the stuff is super sticky and cleans up well with their cleaner.

    New speedometer gear is all greased up, and its about the only thing that's working right. The bike was running so nice until the oil change. :Frusty:

    Thanks again, I'll start to trace down where the issue is with the tach and hopefully in the process figure out why it's not running well.
     
  15. John painter

    John painter New Member

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    Now another vexing issue. Cold the bike starts, or at least the starter starts the bike. Once it's warmed up a bit, the starter does not seem to catch. I still have not been able to trace down where the issue with the tach not working is, all grounds look good when tested. However now the starter is starting to whir once the bike is warmed up a bit, I stop it and try to start it again. Though the bike runs, it is very under powered, so now I'm wondering if only one cylinder is firing - I'll look at that. But gee whiz, it all started with an oil change, just my luck.

     
  16. Diving Pete

    Diving Pete Member

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    so bike is fine when cold & poor when hot -- check Valves
     
  17. Captain 80s

    Captain 80s Member

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    Just for giggles, hook up a car battery via cables to the motorcycle battery (without the car running) and see what she does.
    It seriously sounds like a bad battery and/or charging system issue (even though it will start the bike).
    Cheapest, easiest way to eliminate that as an issue before going too far in other directions. I know it sounds weird, but Squirrel and I have seen this before. It has personally happened to me 3 times on a VF500F.
     
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  18. John painter

    John painter New Member

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    Anyway, I finally diagnosed what happened to my bike with loss of tachometer and no power. I lost coil packs for #1 and #3. After tracing wires and other time wasting activity, I decided to do the obvious.... :Frusty:

    I check for spark. No spark on 1 & 3. Plugs were good (new a little over a month ago), wire from coil to plug good. Testing on coil with multimeter, 0 on the secondary side - definately not good!

    So, I located some coil packs from a known running bike and will swap both 1/3 and 2/4 and replace plug wires, I had already replaced the plugs. After some reading I also realized that

    I still don't understand why the coil pack would have died when I replaced the oil, but evidently it was just a series of unrelated events?

    To add insult to injury, so much for trying to change my photos around.... ended up deleting a bunch of them. :Cry:
     
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