Geauxkart

I have drilled and tapped all items on the block, lots of plugs and fittings! Looks nice. I am having 3 of the ports milled on thursday to get a nice flat surface for the crush washers.



Once it is all ready, I'll post a good write up of what I have done. Hopefully Lynn can review it and give his 2C. It seems so simple now.... Thanks for all the guidance again Lynn.

walwal63

can't wait

k2rdpko

Lynn,



Question on the dry sump setup:



Is the "sump" above the flat plate pretty much empty all the time, since both the scavenge sections are scavenging full time?



On the 3 oil cooler setup, is the 2 cooler in series or parallel?



Seemingly, the coolers didn't look like they have enough air flow thru them in the horizontal mounting shown, comment?



Thanks,



PK

Lynn E. Hanover

The two oil coolers to the left are open to the radiator plenum, and get plenty of air. They are in series, and are run from the scavenge pumps. The right cooler is sitting on a plenum of its own and is fed from a scat tube from the parking light opening beside the brake duct. This cooler is from the pressure side of the pump and after the filter, then to the block on the filter stand. Oil temps at 190 or less in all cases.



There is no doubt a bunch of oil running around on the flat plate of a dry sump system. Under acceleration oil runs to the rear and much is picked up by the rear scavenge pickup. Under braking the reverse is true. The two scavenge pump sections will outrun the waste oil dropping into the sump, And you will notice that air from the engine vent hose is flowing into the engine from the oil tank, instead of the reverse because the volume removed by the scavenge pumps. So, crankase blowby is collected along with the waste oil and is sent through the coolers then into the oil tank. The oil tank is vented into a catch tank, but nothing ever shows up in that tank. Oil, air and blowby gasses enter the oil tank on a tangent, so they spin around the outside of the tank. The large amount of gasses then pop to the center of the tank and the blowby volume escapes up the top center of the tank into the breather line and catch tank. In most cases, all of the oil has been removed, and none escapes to the catch tank.



Lynn E. Hanover



My first gen tube frame from years ago.

k2rdpko

Lynn,



Thanks for the help. I've been thinking about this for a while for a 20B (when and if that happens).



The external oil passage will probably still apply to the stationary gear in the "fat" housing.

Might also need higher capacity (~50%) in scavenge sections, pump section, oil reservoir, cooler capacity, etc....



PK

Lynn E. Hanover

If this engine will be stressed or spend much time above the red line, then the center stationary and front iron should get more oil. You can use just the two scavenge pickups and turn the pump faster, or build a pump with 3 scavenge sections instead of just two. If there is any doubt about adequate oiling, turn the screw on the pressure section up to 110-115 pounds like the FD relief.



Lynn E. Hanover



My tube frame first gen Pport

yallgotboost

here are a few pics of the stock oil pump pickup mod Lynn is talking about.

http://i11.photobucket.com/albums/a170/yal...pg?t=1227476660



http://i11.photobucket.com/albums/a170/yal...pg?t=1227476682



http://i11.photobucket.com/albums/a170/yal...pg?t=1227476788

thebluerx7

is it worth doing the above filter pick up mods,then maybe juts tacking a small steel filter screen back on it again,that should still allow it to flow the extra oil since the pickup has the radius on it?

Lynn E. Hanover

Well, there is a problem Houston........



As has been discovered by so many before you, that screen is dreadful when it comes to flowing any media, oil, hot oil and even air. A rather advanced program was held up over this problem. A company was trying to get a 13B and reduction system certified for aircraft use, but kept overheating the oil. The problem was that they were using the stock oil pickup with the bug screen still in place. That creates too much drag, and the extra suction makes for more oil foaming, and foam in the oil is an insulator, so, the oil will give up less heat to the oil coolers, so, the oil overheats even when the calculated heat rejection of the coolers should have been adequate.



People who manufactured neat looking air horns that should have added HP to engines, installed bug screens over the horns.

It looked good and many people used them, including me. Until I put one on the flow bench (the plans are free) and compared one with the screen to one without the screen. And, as you might expect, without the screen flows twice as much air as the one with a screen. In a fluid, that gets worse. Most of the crap that will kill the bearings, will slip right through the bug screen. So long as you don't use more than three or more pounds of silicone to build an engine, there is little for the bug screen to protect against. I don't use them on anything. The bell shaped inlet on the pickup doubles the flow, and nearly eliminates foaming. So for high performance work it is just as importand as adding the oil.



Lynn E. Hanover

thebluerx7

well,thanks for that,i did the bellmouth thing last night a fabricated a pisckup screen for nothing,guess i will heat it up and remove it.



i do worry that anything in the sump may get into the oil pump? have u ever had a piece of silicone go thorugh the oil pump? results?