Oil pump

5 replies to this topic
  • finthat

Posted April 24, 2009 - 06:47 AM


One more issue. Has anyone ever had the oil pump sieze up?? I bought an '03 with a blown engine. I was ready to put it back together and decided to pull the oil pump to inspect and clean it. The pump was trashed. The larger outer rotor was broken along with the pin and inner rotor. I figure when the bearings and gears started flying that a piece got in and jammed it. I now have a used pump but the outer rotor doesn't want to drop into the case easily, there is signs of something being stuck in the case or that the old pump seized. I have been trying to clean it out with emry paper ect.

I guess my question is how hard should the rotor fit into the case and will i hurt anything by using emry cloth on the case??

  • grayracer513

Posted April 24, 2009 - 06:53 AM


If you are careful, and you clean up well, you can sand out minor damage in the rotor pocket. See page 2-9 of your manual. The rotor clearances are listed there. The inner rotor should have .003~.006".

  • finthat

Posted April 24, 2009 - 07:36 AM


I looks like something got in there and is smeared to the wall. I can get the outer rotor in but it won't turn. When I remove it I can see where the bind points are.

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  • grayracer513

Posted April 24, 2009 - 08:12 AM


Try to use a set of curved "jeweler's" files to work down only the high spots around the gouge, and if you can see that there's a piece of steel jammed into the case, try to pick it out.

  • finthat

Posted April 24, 2009 - 08:49 AM


I have it so I can turn the pump with a screw driver prying on the drive gear. I can't get it to go by hand yet. I was thinking of using a propane torch to heat up the housing to see if there is a thin layer of steel in there it may turn red and peal off easier. Not sure. I may just keep trying to slowly work it by hand. The rotor wouldn't even fit before.

  • grayracer513

Posted April 24, 2009 - 09:08 AM


The oiled outer rotor should drop in and spin easily with one finger.

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