Honda SL350 - no start questions

Discussion in 'Old's Cool' started by cptmoney, Sep 1, 2013.

  1. cptmoney

    cptmoney Two wheels, only one seat

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    Nov 1, 2007
    Oddometer:
    600
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    Western Slope, CO

    Well, not sure what to do with this info just yet. I'm still chewing on it.

    Where would you start, then? Pop off the points plate, and verify that the cam timing is on track?
    #21
  2. Prmurat

    Prmurat Long timer

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    I do not think the bob weight have any chance to stay open... If they are stuck it is certainly in their resting position which the one you want to start the bike. Are the plugs wet after you kicked repeatedly? If not your idle jets are plugged at the minimum. You should take your carbs off and rebuild them, cleaning them completely. You did not say if it was a K0 (CV carbs) or a K1/K2... I have a K1 and this the problem I have when it does not start after a long time it is what I am doing...
    #22
  3. cptmoney

    cptmoney Two wheels, only one seat

    Joined:
    Nov 1, 2007
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    600
    Location:
    Western Slope, CO

    The carbs very well might need a good cleaning/rebuilding, but that still doestn't address the no spark, correct? I'll never know what my carbs are doing if there's no spark.

    I dropped fuel right down the cylinders and she still didn't fire. Soemthing with the spark isn't right at this point. That's what I'm working on now.

    If I can get her to fire, then I'll address the carbs. That make sense?
    #23
  4. concours

    concours WFO for 41 years

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    Yes, it will run FINE on that compression number. It isn't hard to troubleshoot spark now. Clean points? Fine emery cloth then washed with solvent and business card? battery well topped up? Wires NOT shorted? Fuses good? voltage AT points? Kill switch and wiring(contacts corrode, wires get pinched, unplugged)? Spark before but not now is called intermittent, probably gonna be points. My comment about too much ether was based on HAVING spark. Too much can be too rich to fire. All the fire and brimstone stories of ether are pretty trumped up, unless a person has NO knowledge of science, fire safety, etc.
    #24
  5. ndavis

    ndavis Been here awhile

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    I once fixed a friends 350 Honda, someone had put the points cam on 180 degrees out, with the advance unit in your hand if you advance it, the cam will pull off and can go back on in the wrong position. just a thought.
    if you have fuel, spark and compression it will run, but they must be all at the correct time, good luck
    #25
  6. NJ-Brett

    NJ-Brett Brett

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    Yes, with a bike I got that did not run, I would check everything before even trying to start the bike.
    Valve timing, valve lash, wire harness condition, clean the carb float bowls, clean the petcock bowl/filter, set the ignition timing, change the oil, then try and start the bike.

    For no spark, check for voltage at the points (with points open).
    Power should go from battery, to key/kill switch, to coils, to points, to ground. When the points open, the field in the coil collapses, you get spark.

    Once running, you will want to strobe the timing on each cylinder.





    #26
  7. cptmoney

    cptmoney Two wheels, only one seat

    Joined:
    Nov 1, 2007
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    I didn't get to mess with any of it last night; just too much going on. Likely the same this evening.

    I have checked the valve lash. Things were a bit tight there, so I've rectified that - I BELIEVE. I'll double check it, but I think I'm good there.

    I like the 180 degrees out of time option as well. Makes sense why the voodoo is happening the way it is. I'll have to check it all out.
    #27
  8. concours

    concours WFO for 41 years

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    This isn't voodoo, it's shop class 101. IF the thing was firing 180 off, you get popping/backfiring and SOME sign of life while trying to start it. As I read, you got NU-THING. Get the plugs firing outside the cylinders FIRST, then try starting it before diving into something else. If you do this, the benefit to you will be not (possibly) having MORE than one missing element to troubleshoot. Keep checking in, we'll get you there.:freaky
    #28
  9. cptmoney

    cptmoney Two wheels, only one seat

    Joined:
    Nov 1, 2007
    Oddometer:
    600
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    Western Slope, CO
    Getting sunny out here - time to get this old dog back on her feet.

    Let me take a moment to review where I left off...be right back! I'll have many questions, I'm sure...
    #29
  10. anonny

    anonny What could go wrong?

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    Utube has a lot of how to set points videos for CB, Sl, CL 350's, the CB was probably the most popular of the series and all the motors were identicle.
    #30
  11. Scrivens

    Scrivens Been here awhile

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    Swap the plug leads over and see if it fires at all. For a 180 degree twin, a quick check is to drop a screwdriver though the plug hole and gently turn the engine over until the piston is at TDC, (use the crank/alternator timing marks to get TDC on that cylinder) then turn it back until the screwdriver drops about 1/2" - stick it in 4th and turn the back wheel. Remove the screwdriver, put a bit of paper between both the points gaps and turn the engine slowly towards TDC. The points for that cylinder should just be opening as the piston moves towards TDC; check the HT lead for that set of points is going to the correct plug. As long as it is within 5-10 degrees of the correct timing point for the cylinder it should fire. If your gun timing light is a xenon one (not a static light) it won't work unless the engine is running. Two bits of wire fitted with small alligator clips and a 6V torch globe were the basic static timing lights for old coil ignition bikes; solder one wires on the side and the other on the lead centre contact of the globe, and fix the alligator clips on either side of the points. The light will go out as the points open.
    #31
  12. Bill Harris

    Bill Harris Confirmed Curmudgeon

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    This ^^^ has to be the "The Old's Cool Macgyver Post of the Year".

    Heard that before. The correct responsive to that BS is "No problem. Install them and we'll see how it runs. Then we can talk money..." :deal

    --Bill
    #32
  13. cptmoney

    cptmoney Two wheels, only one seat

    Joined:
    Nov 1, 2007
    Oddometer:
    600
    Location:
    Western Slope, CO
    Taking a real step back, here. Starting back at square one.

    No spark - at all. Can't even verify that I have power to the points.

    I should see power at either/both of these leads, as long as the ignition is on - correct?

    I'm seeing nothing. Even when I crank the engine over. Nothing. That's not right, is it?

    [​IMG]

    Do I just need to start chasing power to where I find the gap?
    #33