hcccs

hcccs

Well Known Member
I have been trying to find info in the overhaul & parts manual where you connect the oil cooler. I can't find it so I turn to the forum for help. What are the plugs marked with A, B and C.

acccase2.jpg


acccase1.jpg
 
Look in the back of the "Operator's Manual"

"A" is "To cooler"
"B" is "From cooler"
Not sure what "C" is. Doesn't show up in my manual.
 
Oil cooler

Thanks Mel. I didn't look in the operators manual but there it was. The unknown outlet is not in my manual either. If I can't find out what it is I just have to plug it.
 
DanH said:
"C" gets a #62417 plug and STD-294 gasket.
Click to expand...

Dan is correct, However my parts manual shows that if you use the plug, it also gets a 62415 oil cooler bypass plunger and a 69436 oil cooler bypass spring.
"C" can also be used as an alternate "to oil cooler" connection.
 
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Oil cooler connection again

DanH said:
"C" gets a #62417 plug and STD-294 gasket.
Click to expand...

Dan
I thought this was an outlet to the oil cooler fed through the Vermitherm. I measured the thread to 3/8" but it is probably a 9/16"-18 thread and a standard (#62417?) plug fits in. To connect to the cooler I need a fitting with that thread and a flared tube at the other end. Is my guessing correct and where would I find a fitting like this?
 
COOLER

In most cases, using the Aero Classics cooler as an example, the cooler ports end up one above the other. B should go to the top cooler port and A to the bottom cooler port. If I recall correctly, Mahlon says this is just standard protocol and probably doesn't make any significant difference. Using these ports, all fittings are AN816-8 or 8D, AN 822-8 or 8D or AN823-8 or 8D. Some recommend trying to avoid 90 degree fittings, but I have seen factory 90degree cooler fittings that worked fine. Using C for a cooler line just complicates the fitting situation and adds another place for a leak. The aluminum fittings(D) in aluminum do increase the chances of galling or siezeing the fitting, but if you use titeseal or something similar this is usually not a problem.
 
Cooler

jrs14855 said:
In most cases, using the Aero Classics cooler as an example, the cooler ports end up one above the other. B should go to the top cooler port and A to the bottom cooler port. If I recall correctly, Mahlon says this is just standard protocol and probably doesn't make any significant difference. Using these ports, all fittings are AN816-8 or 8D, AN 822-8 or 8D or AN823-8 or 8D. Some recommend trying to avoid 90 degree fittings, but I have seen factory 90degree cooler fittings that worked fine. Using C for a cooler line just complicates the fitting situation and adds another place for a leak. The aluminum fittings(D) in aluminum do increase the chances of galling or siezeing the fitting, but if you use titeseal or something similar this is usually not a problem.
Click to expand...

Connecting the cooler to the A port means that it will cool all the time. If I understand it right, the Vermitherm valve will regulate the amount of oil that will flow into the oil cooler. What puzzles me is what kind fo fitting you would use to connect to the A port.
 
all ports are pipe thread

All three of those ports have a pipe thread in them. IIRC, it is a 3/8 NPT. Use AN flare-pipe thread adapter fittings.

My IO-360-A1A manual shows either A or C as OK for the "to cooler" port. The B port is always for oil return from cooler. Either way, the oil goes through the spin-on oil filter housing first, and the vernatherm is installed in that housing. When the Vernatherm closes, it sends the oil into the passage that feeds both the A and C ports. When the vernatherm is open, it allows oil to go straight to the pressure regulator passage, bypassing the cooler.

Correction: What Dan said below is correct - my mistake - the oil goes through the filter AFTER coming back from the cooler (or straight from the pump if the vernatherm is open). But Both ports A and C still do the same thing - they send oil to the cooler when the vernatherm is closed.
 
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hcccs said:
Connecting the cooler to the A port means that it will cool all the time.
Click to expand...

It is true that some oil is always flowing through the cooler. When cold it is a small quantity. When hot it is the entire pump output.

If I understand it right, the Vermitherm valve will regulate the amount of oil that will flow into the oil cooler.
Click to expand...

Cold oil has two open pathways. Some oil takes port A and flows through the cooler to port B. Some continues up the vertical passage past port A to the back of the filter adapter housing where it passes through the fully open vernatherm bypass port. The path through the cooler has far more flow resistance than the bypass path, in particular when cold. Most of the oil takes the bypass.

As the oil warms the vernatherm extends, progressively closing the bypass port. More oil flows through the cooler.

When the oil is hot it can only take the port A path because the vernatherm bypass port is closed. All oil flows through the cooler.

Key concept: The vernatherm controls flow to the cooler by how much it blocks the alternate passage.
 
Final

DanH said:
It is true that some oil is always flowing through the cooler. When cold it is a small quantity. When hot it is the entire pump output.



Cold oil has two open pathways. Some oil takes port A and flows through the cooler to port B. Some continues up the vertical passage past port A to the back of the filter adapter housing where it passes through the fully open vernatherm bypass port. The path through the cooler has far more flow resistance than the bypass path, in particular when cold. Most of the oil takes the bypass.

As the oil warms the vernatherm extends, progressively closing the bypass port. More oil flows through the cooler.

When the oil is hot it can only take the port A path because the vernatherm bypass port is closed. All oil flows through the cooler.

Key concept: The vernatherm controls flow to the cooler by how much it blocks the alternate passage.
Click to expand...

When I saw your schematic this is what I thought - oil flowing both ways but regulated by the Vernatherm. I'll use the 'A' port and plug the 'C' port.

What would I do without all knowlegable people in VAF Forum.
 
OIL COOLER

Just checked an 0 320 acc case. While C might appear to accept a pipe thread fitting, it will not. This a straight thread hole for the plug and gasket as posted by Dan. The post by scsmith is incorrect regarding C. The two Lycoming 0 320 "installation drawing rear view" that I have do not show C at all.
 
Thermal prob on "C"

Guys, I am currently undergoing the same investigation. I have an factory direct IO360-M1B. The "C" hole is actually located on the filter accessory housing that bolts onto the accessory case. I also tried to assemble a -8 AN fitting into the "C" opening. It does not appear to be a NPT thread. So I am thinking this is where the oil temperature probe is assembled? That seems to be the only logical answer to me. The manual that came with my Lycoming doesn't illustrate any of this. If that is not right, then where does the oil temp prob typically go? Will that come with my EFFIS EIS install kit?

Thanks,
Brad
RV-8
Austin
 
flyingbeaver26 said:
I have an factory direct IO360-M1B. The "C" hole is actually located on the filter accessory housing that bolts onto the accessory case.
Click to expand...

Unlikely. Study two common oil filter adapter styles in the thread with the schematic, referenced above.
 
DanH said:
Unlikely. Study two common oil filter adapter styles in the thread with the schematic, referenced above.
Click to expand...

Dan, This picture is of an oil filter accessory housing. Notice it has a oil temp probe location. This is the thread that I am referring to. This one just happens to be a right angle version as mine is a parallel version. My point is that I think that this thread for the temp sensor is not a NPT pipe thread. Therefore I'm guessing it must be for the temp probe that uses a slightly different thread. Therefore the "C" orifice in the original picture might also likely be a temp sensor attach point. Possible? Can anybody confirm what the threads on a oil temp probe look like? I don't own one yet.
Processed_Img_1186.jpg


Thanks,
Brad
 
I have been researching this topic because I want to plumb in an oil accumulator. Port "C" is the logical place to connect. This is not a NPT threaded port. It is a straight/bolt thread. Does anyone know of a source for a fitting that will connect this port to a #8 flare?
 
Ron,
Lycoming lists a variety of fittings in the parts catalog:



4,8 is the standard plug.

10 is called "Adapter, oil cooler connection", #71600. The female thread is 3/8 NPT.

18 is called an "Elbow, universal, 75 degrees". The part number is AN777-8D, so I assume the connection is a standard -8 male flare. You would also need 17 (#71623), 19 (#AN901-8A), and 20 (#71620).

9 is called "Connector, acc hsg to oil cooler inlet hose", #69675. A note says "3/8 flared tube connection to oil cooler". Sounds like just the thing for an accumulator.
 
Ah ha!

Dan,
Thanks for this diagram. So now I see that this is truly an oil access point and not just a thermal oil temp probe assembly point. Can the thermal probe be assembled to this location using one of these fittings? Where does it usually go?

Here is a seperate thread I started today, but it shows the locations of this port on my engine. That seems to be the only logical location for the thermal probe to me.
http://www.vansairforce.com/community/showthread.php?t=51944

Thanks,
Brad
 
Brad,
I've borrowed part of your photo from the other thread. See the hex head plug painted the same color as the case, sort of hidden under the breather fitting in this view? That's the "port C" under discussion.

 
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