October 11, 201014 yr Author comment_333184 I am heading to Harbor Freight now for the compression tester.If I do find it is a bent valve should I have concerns about any damage to the bottom end. If so is there a way to check it for damage. I am not sure how many miles are even on this engine, it did run weel prior to the over rev.Glenn Link to comment https://www.classiczcars.com/forums/topic/37341-over-revved-and-no-compression/?&page=2#findComment-333184 Share on other sites More sharing options...
October 11, 201014 yr comment_333189 Don't get overworked yet. Just do a compression test and see what it says. Post the numbers once your done and go from there. Link to comment https://www.classiczcars.com/forums/topic/37341-over-revved-and-no-compression/?&page=2#findComment-333189 Share on other sites More sharing options...
October 14, 201014 yr Author comment_333427 KTM...Thanks.Short delay due to family matters. I hope to do the compression test by the weekend. I will post the numbers then. Thanks for your helpGlenn Link to comment https://www.classiczcars.com/forums/topic/37341-over-revved-and-no-compression/?&page=2#findComment-333427 Share on other sites More sharing options...
October 14, 201014 yr comment_333434 Glenn,When I conduct a differential compression test I put the piston in the cylinder to be checked at TDC, then place the transmission in 1st gear (with the e-brake on and the wheels chocked). If you have a helper. have them sit in the car with their foot on the brake.I then open the valve on the tester to allow 80 pounds into the cylinder. 78 pounds is the magic hold number, but if the cylinder holds within 10% (72 pounds), you have a good/OK cylinder. Below 72 pounds listen to the exhaust, carb or crankcase breather for escaping air. Based on where air is escaping from will tell you where you have a problem, i.e air at the carb is the intake valve, air at the exhaust is the exhaust valve and air at the breather are the rings. If you don't hear air from any of those and can not maintain at least 72 pounds of pressure, spray soapy water around the head gasket. Link to comment https://www.classiczcars.com/forums/topic/37341-over-revved-and-no-compression/?&page=2#findComment-333434 Share on other sites More sharing options...
November 14, 201014 yr comment_335945 same think happened to me. over revved and the lash pads jump. same noise after that and very low compression. check this first. good luck Link to comment https://www.classiczcars.com/forums/topic/37341-over-revved-and-no-compression/?&page=2#findComment-335945 Share on other sites More sharing options...
November 14, 201014 yr comment_335958 I don't think he's ever going to come back and let us know what his compression tests results were...........guess we'll have to wait for next weeks episode!!! :stupid: Link to comment https://www.classiczcars.com/forums/topic/37341-over-revved-and-no-compression/?&page=2#findComment-335958 Share on other sites More sharing options...
September 8, 201113 yr Author comment_365780 Hey sorry- it was valve float. Two valves made contact with two piston tops. i had the engine totally rebuilt. Sorry I did not keep you guys in the loop-thanks everyone for there help Link to comment https://www.classiczcars.com/forums/topic/37341-over-revved-and-no-compression/?&page=2#findComment-365780 Share on other sites More sharing options...
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