[Cardinal767]

Since I’m still waiting on my engine parts for my Lycoming IO-360, I decided to upgrade a few things. Going from an 11 row to a 13 row oil cooler seems to be a good idea. The cooler I received from Vans wasn’t what I was expecting when it comes to increasing cooling efficiency. Is it me, or is this a lot of obstruction of flow on both ends? The 11 row cooler doesn’t have the same construction.

 

[bjdecker]

The first indication of a problem is the word “Niagra”

Do yourself a favor and source a real oil cooler from SW/Troy/Meggitt or, failing that, an HE series from Aero Classics.

 

[agent4573]

In a related post,

stewart warner replacement for Airflow system

I am curious if anyone knows an equivalent replacement oil cooler for the Airflow system 2006x-x that is installed in RV14 models. Throughout the years I have heard that stewart warner is a superior product and if there is one that directly replaces this model Airflow systems, I will be very...

vansairforce.net

There's 2 SW/meggit coolers called out, a 1694 and a 1649. The 1649 appears to be an 11 row mostly equivalent to the 13 row 2006x series. The 1694 is rumored to be a dual pass setup, but the linked technical document doesn't open for me and none of the websites I can find it on have any details listed. My 370 with a 2006x continues to have oil temp issues. Hoping to find a direct replacement with better cooling. Can anyone provide any more detailed info?

 

[bjdecker]

A SW/Meggitt 8406R fed by a 3.5” - 4” duct is sufficient for an IO-360-Axxx, -Cxxx (Angle Valve, Piston squirter equipped). SW 10599R fed by 3” duct is great, 4” even better, SW 10610R, 10611R are more than necessary…

real world - I am flying my second IO-360-A1B6 RV-7 with 3” duct feeding an SW 10599R in central Texas (hot) -- OT is 185-190F at 170Ktas/75F oat/7500msl.

 

[bjdecker]

My 370 with a 2006x continues to have oil temp issues. Hoping to find a direct replacement with better cooling. Can anyone provide any more detailed info?

The SW/Meggit equivalent is the 10611R. On a side note; if you can't cool a 370 oil with a 2006X there's something else wrong -- either the air side isn't flowing (leaks around the end-tanks, duct is small, duct is lossy, transition from duct to OC face is lossy, exit is restricted, entrance is blocked, (deltaP is waay to low) etc.) or the oil side is messed up (small hoses, vernatherm is inop, etc.)

Attached is the SW/Meggitt performance/dimensional documentation:

 

[agent4573]

The SW/Meggit equivalent is the 10611R. On a side note; if you can't cool a 370 oil with a 2006X there's something else wrong -- either the air side isn't flowing (leaks around the end-tanks, duct is small, duct is lossy, transition from duct to OC face is lossy, exit is restricted, entrance is blocked, (deltaP is waay to low) etc.) or the oil side is messed up (small hoses, vernatherm is inop, etc.)

Attached is the SW/Meggitt performance/dimensional documentation:

I've tried everything I could and I can't get it to stay cool. My plenum is new and well sealed (low 320ish CHT LOP cruise with 230 degree oil temps). I've tried remote mounting the cooler with a 4" duct and couldn't climb above 2500 ft before the oil temp got over 220. We moved it back onto the show planes motor mount setup and it cools better, but I still had to pull it back from 70% power cruise the other day due to oil temps climbing through 230. I've replaced the vernatherm with a new one. The oil lines are from TS, -8 lines and were new at install. The cooler is mounted with the exits pointed up (opposite of what show planes shows in the installation) in order to let any air out of the system. I've tried everything except a different oil cooler.

I'm at the point where either the Stewart or aero classic solves my problem, or I'm going to have to install multiple coolers. The Stewart coolers do appear to have a less restricted air side than the 2006x while having similar performance in other areas. So for any given point in flight, it does appear the Stewart will have better cooling, but only by a small margin.

 

[bjdecker]

I've tried everything I could and I can't get it to stay cool. My plenum is new and well sealed (low 320ish CHT LOP cruise with 230 degree oil temps). I've tried remote mounting the cooler with a 4" duct and couldn't climb above 2500 ft before the oil temp got over 220. We moved it back onto the show planes motor mount setup and it cools better, but I still had to pull it back from 70% power cruise the other day due to oil temps climbing through 230. I've replaced the vernatherm with a new one. The oil lines are from TS, -8 lines and were new at install. The cooler is mounted with the exits pointed up (opposite of what show planes shows in the installation) in order to let any air out of the system. I've tried everything except a different oil cooler.

I'm at the point where either the Stewart or aero classic solves my problem, or I'm going to have to install multiple coolers. The Stewart coolers do appear to have a less restricted air side than the 2006x while having similar performance in other areas. So for any given point in flight, it does appear the Stewart will have better cooling, but only by a small margin.

Got pics?

 

[Toobuilder]

I've tried everything I could and I can't get it to stay cool.

I see that you replaced your vernatherm…. Have you tried installing the viscosity valve? The viscosity valve installation made a dramatic difference on my engine

 

[agent4573]

I haven't tried the viscosity valve. I did a little research into it but never pulled the trigger. Maybe ill give that a shot before pulling the trigger on a different cooler.

This was the 4" scat tube setup that overheated in climbout. The plenum is piano hinge along the sides and back for sealing, and a long the front it's well sealed with red RTV. I've done a couple sessions with a dark hanger and lights inside the plenum to seal anything I can find for leakage around the baffles. Don't have pics with the cooler back on the show planes mount, but it seems to be the best solution so far for getting airflow to the cooler.

 

[bjdecker]

I haven't tried the viscosity valve. I did a little research into it but never pulled the trigger. Maybe ill give that a shot before pulling the trigger on a different cooler.

This was the 4" scat tube setup that overheated in climbout. The plenum is piano hinge along the sides and back for sealing, and a long the front it's well sealed with red RTV. I've done a couple sessions with a dark hanger and lights inside the plenum to seal anything I can find for leakage around the baffles. Don't have pics with the cooler back on the show planes mount, but it seems to be the best solution so far for getting airflow to the cooler.

I can see a couple of opportunities:

1. The duct has a fairly tight bend in it; > 90° and is SCAT I think. Reduce the duct size and type -- use SCEET and 3" to help reduce that bend radius. Increase the length of the diffuser walls between the duct and the OC face.
2. Maybe add a bit of tilt into the oil cooler so any trapped air in the oil has a place to go.

See attached - maybe will stir the creative juices:

 

[Cardinal767]

Thanks everyone for the suggestions. Since I’m already out $800 plus dollars, I’ll give this cooler a try. The oil flow rate through the cooler was my biggest concern, but the Texas heat will test it out, especially during the break in period. I’ll supply air with a 4 inch aluminum tube instead of scat hose to avoid the slowing affect of the corrugated hose. I’ll also be building a valve into it for my winter trips to Colorado.

 

[agent4573]

I can see a couple of opportunities:

1. The duct has a fairly tight bend in it; > 90° and is SCAT I think. Reduce the duct size and type -- use SCEET and 3" to help reduce that bend radius. Increase the length of the diffuser walls between the duct and the OC face.
2. Maybe add a bit of tilt into the oil cooler so any trapped air in the oil has a place to go.

See attached - maybe will stir the creative juices:

View attachment 65927View attachment 65928View attachment 65929

Current setup looks like the attached pic, except I put the fittings up instead of down so here no trapped air. Still overheats.

 

[riseric]

Current setup looks like the attached pic, except I put the fittings up instead of down so here no trapped air. Still overheats.

FWIW, here's 1 data point.
I have the ShowPlanes engine mount + 2006X 13 row cooler just like the picture you posted + the butterfly.
IO-375
Zero oil temperature issues.
In fact, I would suggest that it cools TOO MUCH...
Let's say 25°C during climb, half open butterfly is fine and I rarely see above 200F, in cruise 3/4 closed to keep at 180F.
Winter, it's completely closed most of the time.
Cyloinder cooling is pretty good also, I must have good/sufficient cowling airflow.

 

[bjdecker]

@agent4573 Paul,

I made a couple of tweaks ( in green), DanH also suggested this a while back.

One more consideration is pay attention to the fin pitch instead of the # of "rows" -- you'll see that the SW/Troy/Meggit/HE uses a very fine pitch vs the NDM/Airflow X stuff. This equates to greater surface area for the heat exchange => more efficiency. Additionally, the construction of the SW/et al uses a closed end tank, so the seals over the ends aren't necessary.

 

[bjdecker]

Paul,

I saw that you replaced the vernatherm - by any chance did you test either of them to observe correct function? Also, it could be a bit of trash is logged at the seat area keeping the vernatherm from sealing off the bypass passage. Usually a quick visual check of the "cone" will show a witness mark. No witness mark visible, then it might be time to borescope/measure the seat depth and see what's going on.

Agree with Eric - the big/giant airflow performance diffuser along with a 13 row "any brand" should cool the dickens out of the oil -- too much maybe. Time to start looking at other areas.

Is the oil temp sensor calibrated correctly - boiling water test (sea level = 212°F), ice cube, etc. report as expected on the G3X?

 

[Kyle Boatright]

@agent4573 Paul,

I made a couple of tweaks ( in green), DanH also suggested this a while back.

One more consideration is pay attention to the fin pitch instead of the # of "rows" -- you'll see that the SW/Troy/Meggit/HE uses a very fine pitch vs the NDM/Airflow X stuff. This equates to greater surface area for the heat exchange => more efficiency. Additionally, the construction of the SW/et al uses a closed end tank, so the seals over the ends aren't necessary.
View attachment 65934

I think a simple idea to help the situation would be to use something (even RTV) to block the air exit path Brian highlighted in this photo. I expect you're losing a lot of air through those openings. Air is going to take the path of least resistance, and that's it...