Recent content by jpw1400

  1. J

    mercruiser 898, won't run (or will barely run), at wit's end

    I'm ashamed to say that in the course of all this work I rounded off the harmonic balancer bolt, and elated to say the "starter bump" method of removing said bolt worked, and I'll be back at it shortly. More to come (hopefully).
  2. J

    mercruiser 898, won't run (or will barely run), at wit's end

    FWIW, I've swapped in a new coil to distributor wire with no change, and I've tested spark plug wire on multiple cylinders with no change. (And just reiterating... I really appreciate the community support here.)
  3. J

    mercruiser 898, won't run (or will barely run), at wit's end

    Distributor end play? I'm fixated on the fact that spark out of the coil looks good, but spark out of the distributor does not. So I am wondering if the issue is that the distributor shaft has settled a little, and there's not good contact between the center carbon brush and the rotor. I took a...
  4. J

    mercruiser 898, won't run (or will barely run), at wit's end

    I first setup the gap gauge to the coil wire, and saw what looks like good consistent spark. This is in "coil.mov", attached. I then setup the gap gauge to the spark plug wire, and again saw what looks like very inconsistent spark. This is in "from coil.mov". I then did the test you suggested...
  5. J

    mercruiser 898, won't run (or will barely run), at wit's end

    Numbers are better than I had remembered. Pick up a new tester set, and all cylinders were between 140 and 150, dry.
  6. J

    mercruiser 898, won't run (or will barely run), at wit's end

    I've been looking for my compression tester for the past 2 hours, and can't find it anywhere. I believe they were all between 110 and 120 PSI. I firmly recall being pleased with both the readings and the consistency. This was on a cold engine. I will try to pick up a new gauge tomorrow. However...
  7. J

    mercruiser 898, won't run (or will barely run), at wit's end

    I will repeat compression test this evening to baseline.
  8. J

    mercruiser 898, won't run (or will barely run), at wit's end

    Did compression tests when I changed the spark plugs (~2 months ago). All cylinders were in range and consistent with each other. I have tried starter fluid sprayed down the carb before/during/after cranking. Got a good bang out of the carb one time afterwards, but that was it. Do others think...
  9. J

    mercruiser 898, won't run (or will barely run), at wit's end

    Agreed, but I'm having trouble with the "why". Coil test (shorting to engine block) looks consistent; I can't tell if it is strong or not. I can say it looks the same whether I use the existing coil or the new one I put in when I was hoping it was caused by a bad coil. Is there a better way to...
  10. J

    mercruiser 898, won't run (or will barely run), at wit's end

    "What brand of spark plugs are you using." NGK BR6FS, since about 2 months ago. Replacing the spark plugs was something I did early on, after it bogged down once or twice, at wife's suggestion. Seemed to help, but I think it may have just been coincidence in retrospect.
  11. J

    mercruiser 898, won't run (or will barely run), at wit's end

    Choke is closing when it is cold and I pump the throttle, as it should. When it was running OK in driveway, choke (electric) was starting off closed like it should, then opening up after a couple of minutes. The only clear fault I can find so far is the engine doesn't run. :) (Thanks for all...
  12. J

    mercruiser 898, won't run (or will barely run), at wit's end

    Tach has been disconnected since last year. It is disconnected in all these tests.
  13. J

    mercruiser 898, won't run (or will barely run), at wit's end

    It jumps 20K to 25K. I haven't seen it jump more than 25K.
  14. J

    mercruiser 898, won't run (or will barely run), at wit's end

    This is a 1981 Mercruiser 898, GM 305, 2-barrel Rochester carb and Mallory distributor, Pertronix Ignitor II points conversion, Pertronix Flamethrower II coil, MR outdrive on a Sea Ray V197. Ignitor module is powered through a relay and getting direct battery voltage when key is in "Run"...
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