Milwaukee Eight (M8) 2017 and up M8 Air and Liquid Cooled discussion
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Old Dec 18, 2022 | 04:04 PM
  #11  
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Mine run about 225-250 Fahrenheit at the cylinder base. This on a M8 freewheeler which is not water cooled.
 
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Old Dec 18, 2022 | 04:09 PM
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Originally Posted by OldMike
After so many people using this venting system, does this keep the pistons and combustion chamber clean?
Apparently not that's why I'm going the route I'm going now.
 
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Old Dec 18, 2022 | 04:09 PM
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Originally Posted by OldMike
After so many people using this venting system, does this keep the pistons and combustion chamber clean?
minor carbon after 57,000 miles on my stock 114..I don't have any oil blow by or mess issues, runs as good as new and have never bought into the whole catch can thing as something my engines needed..like Bob said, if you have a healthy normal performing engine...well


 
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Old Dec 18, 2022 | 04:12 PM
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Originally Posted by davekp
Mine run about 225-250 Fahrenheit at the cylinder base. This on a M8 freewheeler which is not water cooled.
Thanks thats the info I need to tell Colllifower tomorrow when I go there and make sure their heat resistant hose will work for what I'm trying to do
 
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Old Dec 18, 2022 | 04:15 PM
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Originally Posted by mjwebb
minor carbon after 57,000 miles on my stock 114..I don't have any oil blow by or mess issues, runs as good as new and have never bought into the whole catch can thing as something my engines needed..like Bob said, if you have a healthy normal performing engine...well 
I get it and hopefully it's just my ocd but I figure less oil and condensation going in the better
 
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Old Dec 18, 2022 | 05:14 PM
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Never considered the breather bypass for my `19 FLHT, until I looked at the pistons during a teardown at 11,500 miles (I had to split the cases to look for debris after a cam bearing came out in pieces).




 

Last edited by Dan89FLSTC; Dec 18, 2022 at 05:19 PM.
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Old Dec 18, 2022 | 05:41 PM
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Originally Posted by Dan89FLSTC
Never considered the breather bypass for my `19 FLHT, until I looked at the pistons during a teardown at 11,500 miles (I had to split the cases to look for debris after a cam bearing came out in pieces).

so you can’t believe lack of breather bypass is the root cause of excessive carbon build up, rather an underlying problem existed that adding a catch can is attempting to mitigate the impact. I had 5 times as many miles with a lot less carbon and believe my engine to be operating properly as designed
 
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Old Dec 18, 2022 | 06:26 PM
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Originally Posted by Diesel X
I'm aware of it but maybe for around 45 dollars I can get the same results if I'm lucky. If not that's the next route I'm going to take. Already have the Fueling vented dip stick that seems to not be doing its job.
I hear you, and the cost was the reason I avoided the Trask, initially.
 
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Old Dec 18, 2022 | 06:29 PM
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Last edited by Diesel X; Dec 18, 2022 at 06:31 PM.
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Old Dec 19, 2022 | 07:16 AM
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Originally Posted by mjwebb
so you can’t believe lack of breather bypass is the root cause of excessive carbon build up, rather an underlying problem existed that adding a catch can is attempting to mitigate the impact. I had 5 times as many miles with a lot less carbon and believe my engine to be operating properly as designed
No, there is no underlying problem, the engine did not use any noticeable amount of oil before I tore it down and does not use any oil now.

I think I have the simple engine diagnostic stuff down after 48 years as an aircraft mechanic.

Before I rerouted the breather hoses, I would find oil around the air cleaner, and on the breather hose.

Since I rerouted the breather, I find no oil on the end of the open breather hose (no catch can is used).
 

Last edited by Dan89FLSTC; Dec 19, 2022 at 07:19 AM.
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