Breather on top of motor


4 replies to this topic
  • loudmuffler

Posted October 07, 2006 - 02:36 PM

#1

I saw that it blows air out that hole. Since its blowing air out that hole dont it loose compression? If i blocked that hole up wouldn't it gain commpression?

  • JSanfilippo

Posted October 07, 2006 - 02:43 PM

#2

Thats breather is on the valve cover it has nothing to do with compression.

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  • loudmuffler

Posted October 07, 2006 - 03:34 PM

#3

Thats breather is on the valve cover it has nothing to do with compression.


How come when i kick start it it blows a bunch of air out?

  • JSanfilippo

Posted October 07, 2006 - 03:39 PM

#4

Thats crankcase pressure escaping through breather tube. It has nothing to do with compression.

  • grayracer513

Posted October 07, 2006 - 05:54 PM

#5

The piston pushes 426cc of air around underneath it as well as on top. It has to go somewhere. If you block that breather off on a 426 with manual decompression, the most likely thing is that you'll blow the half moon seals out of the head.





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