HarleyTechTalk

New as they are has anyone tried them ?

sir garfield,
screens  are exactly what i was  referring to  or asking  about  in the above  lifter  tick  post.  the co doe,s  not  infer it will eliminate air.  It doe,s say  it  will  help.  it has been  well known  for some time  that  screens  are  useful in  this area.  in  this case it may be for  nought  because it is installed on the scavenge side.  for air entrainment  removal  it would be better after the pump and before  the oil is presented to  critical  parts i  believe.  but  never  the less.  sounds like an okay idea  to trap particulars when a part self destructs  if it it closely  watched in  my view.  actually, that is the primary purpose for there offering as they  stated.  anything  to help  reduce  the secondary  severe damage  some of you guys are substaining. through  no fault of your own,  if you happen to fall in the group that has over the top runout.  for WHATEVER  reason.  just my  thoughts. at least worth a good discussion here from the more  experienced  twin cam folks. air in the oil is a very valid point i think  in the lifter issue i .  makes alot of sense i believe.  whatever, its an op.  good luck if you do try it. somebody has to go first (g).  lupe

deareated the oil more....  sounds like bad English...

So what they are saying.. The screen puts enough restriction on the suction side the level of oil in the cam chest is deeper allowing less air to enter when scavenged... That's what dry sump systems do, scavenge 60% more than supply so they suck air part of the time.. That is what makes them work correctly..DRY SUMP... now the oil is deeper.. I hope not too deep..and what happens if the new tensioner shoes start to get caught up in the screen.. I guess if it pukes oil you can figure the oil pump is gone or the screen is clogged.. Nice idea though............

Lance
I agree with your thoughts.
I also believe the scavenging is part of the airflow balance the MOCO developed to ventilate the crankcase and is essential to proper oil flow and cooling. These issues delayed the release of the first Twin Cam.
The screen as a protector of the pump seems reasonable but getting rid of tensioners that flake is a better solution IMHO. If metal travels in the pump there are bigger gremlins and the motor needs to be repaired already anyway.

QuoteThe screen puts enough restriction on the suction side the level of oil in the cam chest is deeper allowing less air to enter when scavenged...

Not sure how you get that... You have to have (more bad engrish) the same oil returning to the tank as what is going into the motor.. Unless of course it is either blowing it out the some hole or sucking it past the rings. If the level gets too high the wheels will whip the stuff up and you'll have a whole lot of aeration..  If it does work (it's possible) at de-aerating  the oil, I would bet it's because the screen acts as a point where smaller air bubbles collect on the screen to form bigger ones before they get pulled through.. Bigger bubbles can rise to the top and pop while waiting in the oil tank to get back to the feed tank..

With this in mind and if it works I would theorize that best way to de-aerate the oil would be to install a larger screen (same mesh size) in the oil tank.   The screen that catches the oil as it enters the tank and acts as a air / oil separator.. 

Now getting the air out is probably good for lifter noise, as you don't want air in the lifters.. Randy (RnR might be the original source) at Hyper believes dino aerates less than synth and that it will quiet motor lifters.. That theory seems sound to me..

Max

"smaller air bubbles collect on the screen to form bigger ones before they get pulled through.. Bigger bubbles can rise to the top and pop while waiting in the oil tank to get back to the feed tank"..

SAY WHAT....

The oil tank is a place for storage and cooling of oil. The feed line is on the bottom and gets no air unless you run out of oil in the tank. The scavenge side scavenges more to be able to make up for lag in flow. If you run high rpms lots of oil flows to the top end. When you drop back to an idle the pump has to be able to scavenge a lot more than is being supplied at that moment. During a constant rpm run the scavenge side will be sucking air/oil and by positive displacement pushing it and oil back to the tank. When the oil is pumped back in the tank the air seperates very easily by gravity. THe only potential problem is using an oil suplement that entraps air.... STP or some of the "viscosity modifiers" do this.  The scaveng side of the pump is part of the oil vent system. Ever wonder exactly why an oil fill plug pops out when the tank is too full. The ambient vent line is momentarily plugged by tank oil and the scavenge side of the pump pressureized the oil tank.......

Quoteget back to the feed tank

Should said

"Bigger bubbles can rise to the top and pop while waiting in the oil tank to get back to the feed side of the tank.. "

QuoteTHe only potential problem is using an oil suplement that entraps air...

This is where you and I differ.. I suspect that Oil Temp, Anti foaming additives, size of the aerated bubble , type of oil, and others can effect how quickly the air escapes from the air / oil mix..  I wouldn't doubt that something like STP would mess it up.. I've seen Marvel Oil do it..

QuoteThe scaveng side of the pump is part of the oil vent system.

Sure is..

QuoteEver wonder exactly why an oil fill plug pops out when the tank is too full.

One of the reasons why they moved the vent line on the early TC  baggers from the front of the tranny to the oil fill hole..

Max

  You guys keep at this and somebody's going to end up a bubble off !      Rick