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  #61  
Old 02-22-2010, 09:37 AM
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chances are you cooked the rings or there is carbon on your valves and seats preventing the seal it needs.
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  #62  
Old 02-22-2010, 02:19 PM
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If you have the valve lapping stick and some compound, do the valves and get a head gasket. No point in getting new rings if you ran that engine without an air filter, becuase its cooked, after doing those 2 things you should get atleast 70 psi which is good enough to run a kart on. please let us know what compression you get, thanks
  #63  
Old 02-22-2010, 02:28 PM
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save yourself guessing and get the compression and rip the head off the engine.
  #64  
Old 02-22-2010, 02:34 PM
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I have never come across a small briggs/tec/honda etc with "burnt" valves, the valves do get plenty of carbon build up, and that can cause them to not seat properly.
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Old 02-22-2010, 04:11 PM
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almost all briggs i see have slightly burnt valves, not always bad, but they can always be much better. I have ALWAYS gained a minimum of 15 psi from lapping and up to 50psi gain from lapping a burnt valve.
  #66  
Old 02-22-2010, 05:46 PM
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Quote:
Originally Posted by solomon View Post
almost all briggs i see have slightly burnt valves, not always bad, but they can always be much better. I have ALWAYS gained a minimum of 15 psi from lapping and up to 50psi gain from lapping a burnt valve.
*sigh* dude you know if a valve was burnt... it would be unable to use in a engine

a kruded up one will make it not seal right then of course a lapping will make it seat better... it makes brand new valves seat better.
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Old 02-22-2010, 10:34 PM
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well anyway im sure a valve job would do it better, they always do.
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Old 02-23-2010, 10:35 AM
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but Kaptain, he said it wont even start off starting fluid, which says that carburetion is not the problem. Has to be compression issue
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Old 02-23-2010, 08:09 PM
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Or spark... Just because the spark will jump the gap at atmospheric pressure doesn't mean it will jump the gap at 60-120psi.
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Old 02-23-2010, 09:20 PM
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agreed
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Old 02-23-2010, 09:57 PM
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could we possibly get a video of you cranking the engine? would help us dearly... we are working on 4 pages of suggestions but no result.
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  #72  
Old 02-23-2010, 10:07 PM
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haha i know right? Its either, compression, or weak spark

my bet is on compression
  #73  
Old 02-23-2010, 10:20 PM
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+1 it has to be a bad valve or something simple, even briggs with weak comp will try to fire, and bad sparkers will still run too.
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Old 02-24-2010, 12:28 AM
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I Agree 100% BriggsTwins, My only two guesses are, head gasket Or bad valve.
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Old 02-24-2010, 05:59 AM
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Does it have points?
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  #76  
Old 02-24-2010, 06:13 AM
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Quote:
Originally Posted by solomon View Post
but Kaptain, he said it wont even start off starting fluid, which says that carburetion is not the problem. Has to be compression issue
Wow i was out of it, i posted that in the wrong thread, that was meant for yours about the tecumseh...
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  #77  
Old 02-24-2010, 08:42 PM
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Yea I have a briggs that will not fire because of compression actualy i ran w/o air filter too and it tore up the rings and then started to scratch the sides of the cylender
It will not start with staring fluid eather so it must be compression
  #78  
Old 02-24-2010, 09:29 PM
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haha yup, i did that to a 5hp myself =P, it still ran, just had no power haha
  #79  
Old 02-26-2010, 12:39 PM
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Ok guys, thanks for all the info so far. So it sounds like a compression problem. When Im home next weekend for spring break I will try to find time to run a compression test on it and pull the head to see whats going on. I will definitely post my results here.
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