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About mark3066

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  1. mark3066

    2002 CR250 Coolant leak into crankcase. Stumped!

    Found the leak. It is not a crack, but the fluid is actually weeping through the water jacket in a small section of the the intake port. I'm guess stop leak may fix it, but will opt of a new cylinder. Enclosed is the video. Explains why replacing all the gaskets didn't fix the problem. https://www.youtube.com/watch?v=RWY81odrnIE
  2. mark3066

    2002 CR250 Coolant leak into crankcase. Stumped!

    Thanks. I left the head on and removed the cylinder/head assembly. I will try to pressurize the head and cylinder. Hopefully I will be able to find the crack. I inspected the cylinder and there is nothing obvious I can see.
  3. mark3066

    2002 CR250 Coolant leak into crankcase. Stumped!

    Finally got a chance to pressure test the system. Took the muffler off and the sparkplug out. Drained the coolant and fashioned a listening device by using an old stethoscope by removing the diaphram and used the open hose. Pumped up the system to 10PSI and began listening. Noticed is would loose a PSI or so a minute. Listened around the exhaust port and inside the cylinder and could not hear anything besides the seashell noise Removed the carb and reeds and listened around the base gasket and heard nothing around the front where I suspected. I then went up the right side cylinder port and low and behold I heard hissing.....This is probably not good. I don't know what it could be besides a crack in the cylinder. Does anybody have any other ideas or know if this is repariable? Thanks
  4. mark3066

    2002 CR250 Coolant leak into crankcase. Stumped!

    I did run with the cap off and saw it was foamy, thought this was normal Turbulence....I guess not... Just found a mityvac pressure tester on line for $30.00. Will pressure test shortly. Thanks for the suggestions.
  5. mark3066

    2002 CR250 Coolant leak into crankcase. Stumped!

    Just though of something. Had a wreck a couple years back. Shortly after that it started leaking. Maybe something got whacked, since the engine is mounted to the frame via 3 crank case bolts and 1 support on the head. What are the odds that the tabs on the base of the cylinder got bent slightly. I checked the head for flatness, but the base was far more difficult to check.
  6. mark3066

    2002 CR250 Coolant leak into crankcase. Stumped!

    There are a few questions so I will try to answer as best I can How do I know its coolant? I pulled the carb and reid case and it was full of antifreeze. Drained the trans oil and it was fine. Seems coolant is only in crank case lower end by bearings Did I replace 33? Yes, that was what I suspected, but if this was leaking, the weep hole between the cases should have showed signs of coolant. It's new right now and it's still leaking. I'm guessing there is a crack in the jug someplace I can't see. Is there a way to test this theory?
  7. mark3066

    2002 CR250 Coolant leak into crankcase. Stumped!

    Yes I did, as general maintenance and precautionary. Although the pump seals are all in the trans. Where I have no indication of coolant.
  8. Have a coolant leak into my crank case and here is what I've done. Replace head and base gasket. Same leak Split cases replaced gasket and head and base gasket again. Still leaking Here is what I checked Head flatness by placing 0.002" feeler between studs one at a time without gasket. Tight everywhere Inspected for cracks Plugged bottom cylinder holes filled it antifreeze no leak detected No drips on the ground just into crank area Trans oil normal Always checked coolant before running so never been overheated Any guidance would be appreciated. Been fighting this for 2 years!!! I'm guessing something's warped, bot can't figure out what. Any guidance would be appreciated.
  9. mark3066

    Coolant in crank 2003 CR250 Best way to dry out

    Replacing the seals is a great idea. I loosing a little trans fluid anyway. Should be putting back together shortly
  10. mark3066

    Coolant in crank 2003 CR250 Best way to dry out

    Great thanks. That's is what I did. Checked bearing play and all looks tight. Coated everything in 2 stroke oil. Now It time to put together.
  11. quick question. Had a leaky base gasket. Crank filled with coolant over the winder up to the top of the crank. Head and Cylinder is removed and bike is sitting upside down. No signs of rust. What is the best way to get all the water out. Heard some put Kerosene in the crank and then drain. Any help here would be appreciated.
  12. mark3066

    Jetting Mystery 1996 RM125

    Once you gain access to the seals they are easy to replace. May want to replace water pump seals also while your in there. The shaft was pretty worn on mine ended up replacing both bearing, the shaft and the WP seals.
  13. Anyone have any further info on this. I have a slide the I know is rich off idle, instead of buying a new one, or machining the angle, would this notch help the off idle mixture, if the slide did not include it originally? http://i52.photobucket.com/albums/g2/scot_douglas/DSC_0060.jpg
  14. mark3066

    Jetting older Bikes

    My plug is actually black and dry, but I may be ridding slower than you. If you crack the throttle just a little, does the bike sputter and smoke. That is where I think I have my problems, which the needle diameter should address. Another thing, if you don't get enough time on the sparkplug it may be brown on its way to black. I pulled mine after about 10 minutes and thought I nailed the jetting problem, nice and brown, but it was just on its way to black:banghead:. As another note, I have don't have a 250, but a 60 sj seem a little large. My stock SJ is 50, went all the way down to 35 with no change in low speed operation, that is what led me to the needle diameter.