Oil Cooler Hose Routing question for M20J (A3B6D/Dual-mag engine) owners.

[cnoe]

Many of you are like me and have hundreds, if not thousands of pictures of their plane, both inside and out. So if anybody has a picture of the back of their engine showing how their Oil Cooler Hoses are connected and routed I would be most appreciative.

To elaborate... I plan to replace my oil cooler and hoses soon and have found a possible discrepancy in my existing installation setup. Because of this I would like to confirm with at least 2 other J owners their hose connection/routing.

I have referenced the Mooney Parts and Service Manuals and though it's not explicitly clear it does appear that one hose runs from the engine port just above/adjacent-to the Vernatherm to the lower (bottom) port of the oil cooler, while the other hose runs from the engine port near the middle of the accessory case to the upper (top) port of the oil cooler.

In my J these connections are reversed with the first hose described above running to the upper oil cooler port. I assume that the previous engine installer made their own hoses during installation and did not follow the original hose routing/connections.

I have spoken with both Lycoming Technical Services and Aero-Classics Oil Coolers about the proper connection order and the concensus is that it's "okay" in this application for the oil to flow either UP through the cooler or DOWN through the cooler but I'd like to employ the original factory routing.

While I had read and was under the impression that the "correct" flow would pump the oil IN to the lower port and OUT the upper port this is apparently opposite of what I believe to be the original Mooney installation.

So, if anybody can chime in with comments, or better yet a picture, I'd love to see how your J's cooler hoses are set up. For reference I will attach a pic of my current routing below. Note the two orange fire-sleeved hoses and compare to yours.

Thank you,

CNoe

 

 

[EricJ]

Generally on race cars it's common practice to pump the oil in the bottom and take it out the top so that it is more reliably full of oil rather than air bubbles.   This maximizes the cooling capability of the cooler since the oil will spend more time in the cooler if there isn't air in there.

[cnoe]

Thanks for your input.

That’s what I was thinking too. And I saw reference to that method recently as well, perhaps on Beechtalk. But it appears that the factory Mooney installation was opposite of that, but I’m not 100% certain.

Lycoming confirmed the actual flow direction for me this morning but said that proper flow through the cooler was determined by its manufacturer. Aero-Classic Coolers said air entrapment was no issue in any configuration (up, dowm, or sideways).

I just want to confirm that Mooney directed the flow from top to bottom (for whatever reason).

CNoe

[carusoam]

Interesting question for the @M20Doc (oil flow direction in oil coolers...)

Best regards,

-a-

[cnoe]

Thanks for looking Jim. Byron swapped out for the newer style engine so his routing is different now. He may have some old pics though (Jetdriven?).

Manual shows what appears to be downward flow but the engine connections aren’t clear. The 90 degree hose fitting should connect just above the Vernatherm which would correspond with this drawing. 

CNoe

[toto]

For whatever it's worth..

 

[cnoe]

Thanks Toto. It’s a little dark along the firewall but appears that your accessory case port may be routed to the upper cooler port similar to the diagram above.

I also found this pic by @201Steve from a post in February that clearly shows that same configuration.

You can see this is different than the pic from my plane.

Can anybody else confirm theirs?

CNoe
 

Edited pic to show flow on oil cooler hoses as confirmed by Lycoming Tech Support.

 

 

[OR75]

[cnoe]

Great pic @OR75; thanks! Yours is clearly configured as shown in Mooney’s literature. And mine is not.

I will likely revert to that setup when replacing the hoses. I’m curious if there will be any noticeable difference in cooling. I doubt it but will report back here afterwards.

In the meantime if any others want to add to this thread, their input and/or pics are welcome. 

[Bartman]

This was early during my installation earlier this year. Some things were changed and re-routed, but no change to the oil cooler hoses. 

[cnoe]

Thanks Bartman. Yours is the only one I’ve seen so far with firesleeve on the oil-pressure/gauge hose. That’s actually not a bad idea. I replaced that hose last year and may add firesleeve after the fact; it’s only about $10/ft on Spruce. 

CNoe

[jetdriven]

the 124J hoses are similarly priced, and have an integral silicone fire sleeve, are a smaller OD, and have a better bend raduis

[Bob Mackey]

Lots of good photos up above, but most are pretty crowded. For clarity, I disassembled the airplane to get this photo (not really):

 

So here's my question. This photo, which I actually just grabbed off the web and annotated, shows oil ports A and B.
Which one is to-the-cooler and which one is from-the-cooler?

And that port C, my engine has a big hose to nowhere attached there.
Where could it possibly go?
It has the next size larger AN fitting. I think a -10, while A and B are -8 fittings.

 

 

Edited February 9, 2023 by Bob Mackey
formatting for clarity

[carusoam]

Bob,

While you wait…

From theory…

1) It helps to know where the oil pump is… oil goes to the oil cooler’s vernatherm…from there…

2) Oil typically enters the bottom of a heat exchanger before leaving at the top… 

3) For real answers to your questions… consult the manuals for hose routing… Maintenance, and parts manuals are moderately good for this…

PP guesses only waiting for somebody that actually knows…

Best regards,

-a-

[PT20J]

C is the suction screen which in this example has a sump heater installed instead of a plug.

[Guest]

10 hours ago, Bob Mackey said:

Lots of good photos up above, but most are pretty crowded. For clarity, I disassembled the airplane to get this photo (not really):

 

So here's my question. This photo, which I actually just grabbed off the web and annotated, shows oil ports A and B.
Which one is to-the-cooler and which one is from-the-cooler?

And that port C, my engine has a big hose to nowhere attached there.
Where could it possibly go?
It has the next size larger AN fitting. I think a -10, while A and B are -8 fittings.

 

 

The “B” fitting should be to the cooler, it’s beside the vernatherm valve.  Not that it really matters, the hoses will only reach the correct ports on the cooler, and the cooler really doesn’t care which way the oil flows through it.

[Bob Mackey]

13 hours ago, PT20J said:

C is the suction screen which in this example has a sump heater installed instead of a plug.

Does anyone know why a hose connection might be on port C instead of the plug that normally covers the suction screen?

The engine I have here has a -10 AN hose connection there. It really doesn't make sense to me. I usually expect an even number of inlets and outlets.

[EricJ]

27 minutes ago, Bob Mackey said:

Does anyone know why a hose connection might be on port C instead of the plug that normally covers the suction screen?

The engine I have here has a -10 AN hose connection there. It really doesn't make sense to me. I usually expect an even number of inlets and outlets.

If it came from an airplane with an additional oil tank that'd be an easy way to get more oil into the sump.   Maybe for an over-water ferry or something?   That's all I can think of.

Edit:   I'd be skeptical of any hose there, since that's supposed to be the suction screen and putting a hose there means any debris isn't really captive.

[Guest]

38 minutes ago, Bob Mackey said:

Does anyone know why a hose connection might be on port C instead of the plug that normally covers the suction screen?

The engine I have here has a -10 AN hose connection there. It really doesn't make sense to me. I usually expect an even number of inlets and outlets.

That fitting would normally be part of a Christian inverted oil system, definitely not used on a Mooney.

[201Steve]

On 9/18/2020 at 12:19 AM, cnoe said:

Thanks Toto. It’s a little dark along the firewall but appears that your accessory case port may be routed to the upper cooler port similar to the diagram above.

I also found this pic by @201Steve from a post in February that clearly shows that same configuration.

You can see this is different than the pic from my plane.

Can anybody else confirm theirs?

CNoe
 

Edited pic to show flow on oil cooler hoses as confirmed by Lycoming Tech Support.

 

 

I was looking at the picture before I read the text and thought, damn that looks exactly like my engine. Wire bundles and everything!!!

[haymak3r]

for what it's worth:

[Guest]

30 minutes ago, haymak3r said:

for what it's worth:

A few items of interest in your picture.  Your oil filter appears to be wired to your engine mount, (they don’t vibrate at the same rate,)the clamp securing the oil cooler transfer hose is loose, the back shell clamp on the firewall cable is missing and it appears the cabin side of the connector doesn’t appear to be secured to the firewall.

[Guest]

I missed one other, the oil pressure transducer appears to be screwed directly into the engine, normally they are installed in the end of a hose and remotely mounted.

[201Mooniac]

2 hours ago, M20Doc said:

A few items of interest in your picture.  Your oil filter appears to be wired to your engine mount, (they don’t vibrate at the same rate,)the clamp securing the oil cooler transfer hose is loose, the back shell clamp on the firewall cable is missing and it appears the cabin side of the connector doesn’t appear to be secured to the firewall.

Amazing what a trained eye will see

[Will.iam]

2 hours ago, M20Doc said:

I missed one other, the oil pressure transducer appears to be screwed directly into the engine, normally they are installed in the end of a hose and remotely mounted.

Damn i need to post a picture of my engine with the cowl off to let doc see what is not right with my setup. Great eye doc!