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Mitsubishi BD2H dozer runs rough and burns oil after tipped

Dave Hass ยท 2020-10-20 11:42

Hello, I am new to the forum. My Mitsubishi BD2H dozer was recently tipped over on its left side in an accident downhill, it ran for around 10 seconds at high throttle and I quickly choked the air intake after the fuel shutoff would not kill it, as it was likely running on oil. After righting the tractor we let it sit for several weeks then I rotated the engine by hand after pulling the glow plugs and around 1/3 cup of oil came out of cylinders 3 and 4. After several hand rotations I started it and let it idle. It ran ok but oil was dripping out the exhaust. After test driving it I am getting clouds of blue smoke at revs, oil dripping out exhaust, and loss of around 1 quart of oil on the dipstick after several minutes. I suspect oil got into the cylinders during the rollover and hydrolocked it causing at least 1 bent rod. The tractor ran great before this just mild oil burning. I have drained the oil now and it seems it had tiny metal shavings. Do you think I should pull the oil pan and inspect crank/ bearings? If I can get away with replacing rod(s)/bearings that would be ok at this point. It has a S4S non turbo engine. Thanks in advance!

Replies3
  1. #1mks2020-10-20 14:57

    I think you need to find out how the oil is getting in. Pulling the pan would give you a look at the bottom of the pistons and maybe some cylinder wall. Or charge three and four with air. Need to sure all valves are closed. A borescope might be the easiest way.

  2. #2Tones2020-10-20 22:11

    I hope you ran this engine at WOT. Getting good heat in is very important to oil residue out of the combination chamber

  3. #3Dave Hass2020-10-21 11:27

    Yes, I think this weekend I will put fresh oil and filter and run her again until at operating temp/WOT. I just want to play it safe and try to prevent possible damage to the bottom end if I can.