6BTA Oil leaking from Aftercooler

[Daniel]

Hi.  I recently noticed that oil has been leaking out of the top part of the aftercooler.   The aftercoolers were replaced about 6 months ago on both engines since the core had seized and wouldn’t budge.   Originally, I thought the oil was coming from the small filter of the recently installed envirovent but after further investigation I am now thinking it is coming from the aftercooler.  The envirovent filter does leak moderate amount of white smoke to which my mechanic is blaming on blow by.   The puke bottle is catching some oil and is about 1/4 full.   I also changed the original hose that came with the envirovent (the part from the valve cover to the vacumn break) because the hose was heating up and warping.  

 Other observations is that there’s black soot stains where the turbo connects to the manifold and there is some turbo lag when getting to about 2k revolutions which is noticeable when compared to the other engine but once it catches up everything functions fine.  At first, I thought the oil was getting into the aftercooler from the actual envirovent system but I checked the inside of the main air cleaner as well as the intake side of the turbo and did not find much oil there.   Now I am thinking maybe the turbo is leaking and wondering if that could be causing the lag, blow by, and oil getting into aftercooler.  Could that be a possibility?

Topic

[Rob Schepis]

Yes, many variables as noted by Tony, but there is always some level of oily mist running through the air side.  For example, here’s my two that I pulled apart a few days ago – these engines have no blowby, zero oil consumption and maybe a 1/4″ of collection in the puke bottles after a 100hr season.  Yet can see the oil residue on the fins on both after 3 seasons since last cleaning.

[Daniel]

Hi Rob, 

Thanks.  It does seem to be leaking.   I will ask the mechanic to pressure test it as is.  My concern is that its oil that is leaking.  Should any oil be in the air side of the aftercooler?

 

thanks for your help

[Daniel]

Hi Tony, 

 

#1——How much oil in getting the Envirovent CCV drain bottle? – I am getting half an ounce every 8-10 hours. 

#2—if close to an ounce per 25 hrs ( 1/2″ or so) , then you need an extension kit for the it or upgrade to the new “dual valve cover” unit. – I will proceed with the dual valve cover – wasnt able to locate it on the website to purchase but will contact your team to purchase.  

#3—How sure of you of that  aftercooler you have? – I am now having my doubts.  At the time I did not have the funds to purchase both original and new and someone recommended me this company in Florida that made their own aftercoolers for their rebuilt engines.  

#4–Exactly how much oil is in your oil pan sitting at the dock “right now” engine off.. Simple question. – I will attempt to verify when back on the boat this weekend.  I am going to compare the dip sticks as maybe they are not original and maybe this caused overfilling of oil.  Do you suggest I drain the oil and measure how much was in?

 

Thanks for your help!

[Rob Schepis]

That “knock-off” aftercooler looks to be leaking through the housing casting which is on the air side which will effect boost/performance.  I’d get that thing pressure tested as-is before breaking it down as part of your trouble shooting

[Tony Athens]

#1——How much oil in getting the Envirovent CCV drain bottle?

#2—if close to an ounce per 25 hrs ( 1/2″ or so) , then you need an extension kit for the it or upgrade to the new “dual valve cover” unit.

#3—How sure of you of that  aftercooler you have? 

#4–Exactly how much oil is in your oil pan sitting at the dock “right now” engine off.. Simple question. 

[Daniel]

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