98 overheating

1 reply to this topic
  • Lance_Blair

Posted June 23, 2001 - 11:22 AM


I just added a bigbore kit and new crank (RB) and am having overheating problems. I found oil in the water after a desert race. Replace the WP seals and bearing and the Radiator cap. Found oil in the water. Inpected head and base gasket. No apparent problems. Going back to water pump. Ordered a new impellar and shaft. Someone sujested jetting. Not real good in this or any other area to be honest. Missed a race today because I can't figure it out. Not real happy! Any ideas or experiances in this area?

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  • sirthumpalot

Posted June 24, 2001 - 06:53 AM


Did you retorque the head bolts after it ran for a while? I don't know about these gasgets specifically, but on some other rebuild jobs I've done it's not unusual for you to have to retorque a short time after installation; usually after the first run or after break-in. It's also not unusual to blow a head gasget because of overheating. If this problem persists then you may want to remove the head and check the head and the top of the cylinder to be sure that they are both still flat (not warped). A warped head will cause a leak.

Actually now that I think about it, are there any pressurized oil passages which run between the cylinder and the head on this motor? It may be all external oil lines, in which case I doubt that a leaky head gasget could cause oil in the water, though it may still cause water in the oil if the leak is near the space where the timing chain runs.. Maybe Hick will chime in with some advice, he seems to know this motor pretty well.

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