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8 row oil cooler on baffle of angle valve

MASpickard

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I have about 800 hrs on my IO-390 in my -8 with the standard 7 row cooler on the baffle. I also have the shutter door that Vans sells. It does fine at economy cruise but extended climbs, slow flight, hot days, etc can push oil temps up to 220 or so. I am thinking that an 8 row cooler and removal of the shutters door would do the trick. Has anyone successfully fit an 8 row (Aero Classics HE 8001599, or SW 10599r) on the baffle of an angle valve? I know a 13 row is recommended but it seems like overkill being that the 7 row works. I dont like the Show Planes 13 row kit as it would blow hot air right on my dual Lightspeed boxes…….and the rubber seal doesnt appear to provide sufficient clearance for engine movement. I would really like to fit an 8 row right where the existing 7 row is.
 
It can be done

Here are some images of my installation. I have been flying with this setup for 9 years with no issues. I laminated a sheet of steel in the aft baffle to support the oiler and a steel reinforcing angle on the corner brace. The trick to make it fit is to angle the cooler so the outboard corner is lower than the inboard to follow the contour of the cowling. This puts the bottom outboard cooler attach bolt inside the left side baffle. A -3 nut plate fits on the aft baffle and sits in the recess of the cylinder just below the access panel for the rocker arm shaft. I did have to relieve the inboard aft flange of the cooler to provide clearance from the engine mount. I have an RV7 with an IO-360a1a. Oil temps in south Texas summer rarely get over 195.
 

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Thanks for the info. I may have a bit less real estate to work with on my -8. I have worked my order of preference down to:
Airflow Systems AS-2004x 10 row on baffle…..only a little larger than the 8001599
Aero Classics HE 8001599 8 row on baffle
Ndm 200003a 9 row on baffle
Airflow Systems AS-2006x 13 row remote
Airflow Systems AS-2004x 10 row remote
Airflow Systems AS-2002x 7 row on baffle and remove shutter
 
Hate to nay say about baffle mounted oil coolers, because you have 800 hours trouble free structurally. With oil cooler weight (cooler, hoses, oil in cooler and hoses) weight on the baffle in my experience will result in cracks at some point. So always not a fan of this mounting, my bias.

220F is hot but at the limit. Suggest Aeroshell 100/80 (or W100/W80) and change every 50 hours or 3-4 months (regardless of hours) which ever comes first. Do try and keep temps as low as possible with shallow climb, step climb. I'd strive to get lower OT as well. A new cooler and installation may help.

Keep in mind original Stewart Warner oil coolers (no longer made by SW) are more efficient than new ones. "Classic" makes a fine cooler but they don't have as much cooling area as original SW coolers. They are up front about that. If you are going from an original SW to Classic you may find it not cooling as well. I could have my story wrong but there is some truth to it. Call Classic and ask them. Tell them what you have.

Also you can increase your cowl exit air. The engine you have I think has piston oil squinters. Much heat is being dumped into the oil. What are your CHT's when your oil is 220?

I have no idea if you can mount a monster 13 row cooler on your baffle. Get one or mock it up and see if it will fit. I suspect it will not. I would not disregard the remove oil cooler idea.

As far as light-speed EI boxes can you move them to the cool side of the firewall? Even without out oil cooler, the area under the cow is hot hot hot. The engine and exhaust pipes are radiating and convective HEAT. Your EI boxes see that heat and get hot, especially after shutdown and heat soak. Radiant heat does not require air flow.... You might be surprised how hot those LS electronics are getting. Put some thermocouples on them for temperature reading.
 
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Keep in mind original Stewart Warner oil coolers (no longer made by SW) are more efficient than "Classic".

Yes and -- Meggitt still produces the Stewart Warner (AKA SW, Troy, South Wind, Harrison) variant oil coolers...$$$ however.
 
Actually have over 1500 hrs on my baffle mounted cooler. Normal cracks early on but reinforced and no problems since.

What makes you think the SW are more efficient than the Aero Classic HE (High Efficiency) series? Do you have some data? I will probably go with an Airflow Performance X series if I can as their data shows superior performance. No matter what, if I replace my 7 row with an 8, 9 or 10 row, all of which have more area, all of which may fit on the baffle, and I remove my shutter, I should get some improvement and some is all I need.

I have squirters which is why I have max CHTs of only 300 at economy cruise. OT at economy is just right…..180-190. Climbing on a hot engine, fast/extended climbs, slow flight on hot days are the only problem. Got up to 220 when flying at 90 kts on very long approach on a very hot day into Osh last summer. Lycoming states 245 max continuous and normal continuous of 185-210……my existing 7 row is getting the job done but I would like to stay at 200 or less at all but the most extreme conditions.

13 row wont fit on baffle, and if it did would probably overwhelm my reinforcing structure and lead to more cracks. If I have to go remote, I will try to fit a 13 row but not the Show Planes route.

Out of real estate so Lightspeed is staying put. Klaus has no problem with hot side installs if done right. Mine are mounted low and toward the outside of the firewall, inside a custom heat shield with a cooling tube. +1000 hrs flight on this with no problems.
 
You say you have the "standard 7 row cooler" is that the Niagara Vans cooler? I assume yes (may not be correct)as it fits the shutter.

If this case I had looked at the Niagara 20003a - a 9 row unit. attached are the spec sheets for the -2a and -3a for comparison. I despise that shutter, but we have few options for the baffle mount. It would certainly be a PITA to change it on a completed plane to firewall mount, but that seems to be the only way to get more cooling and control temps in winter (other than an oil valve). Look carefully at the -3a flange dimensions they are very close to the -2a and just may fit your installation with minimal change since the holes are slotted.

Last comment - CHT as measured has no indication or relation to actual piston temps. I have tested with lots of barrel restriction and used a lower barrel flange thermocouple (Lycoming recommendation). While barrel and piston temps went up CHT was unaffected. Your low CHT's are a result of angle valve fin density not oil squirters.

The sheets will be hard to interpret, but the 9 row will provide about 30% more cooling (BTU's) than the 7 row at the same air pressure drop. The 9/7 ratio is the clue as the other HX design is the same since it's the same manufacturer.

View attachment 20002A-Specs-and-Flow-Graph-NAP-header.pdf

View attachment 20003A-Specs-and-Flow-Graph-NAP-header.pdf
 
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I have an Aero Classics 7 row cooler now……pn 8000075. This is a “standard” Aero Classics cooler, not one of their HE models.

My understanding is that the Niagara/NDM/Harrison coolers are comparable to the Aero Classic standards with respect to both price and performance…..they are both relatively cheap and relatively inefficient. So, I presently have a relatively inefficient 7 row. I have over 800 hrs on my YIO-390-EXP using this cooler and overall, it works….just a little marginal. The push to a 13 row high efficiency model for these engines seems to be overkill.

My understanding is that the Stewart Warner/Meggitt coolers are comparable to the Aero Classic HE series, with both being relatively highly efficient and high price. All literature and vendors state the HE series as being an FAA/PMA approved direct replacement for the SW and with the same or better performance.

The Airflow Systems X line also looks good. They are comparably priced, and I suspect comparable performance, to the SW and HE lines. Their performance plots show them superior to the Niagara and Aero standard line……but don’t show comparisons to the SW or HE.

Looking at the dimensions, the following are all about the same size.
10 row Airflow AS-2004X
8 row Aero Classics HE 8001599
8 row SW/Meggitt 10599R
9 row Aero Classics standard 8000074
9 row Niagara 20003a

I am going to try to get the 10 row AS to fit. It is a little bigger than the others so if it doesnt fit, maybe the 8 row HE or SW will fit. These are all of the high efficiency models. If none of these fit, I doubt the lower efficiency 9 row AC standard and Niagara will fit either. As far as baffle mounted is concerned, the only remaining option would be to replace my existing low efficiency 7 row with a high efficiency 7 row and remove the shuttle. Neither SW/Meggitt or AC HE make a 7 row. AS does make a 7 row in their X line. I may see if they have any performance data comparing it to my existing AC standard 7 row.

If none of this pans out, then I am going to have to go remote. If I have to do this, i will fit the largest, most efficient unit in than I can, preferably with a 5” duct.

A good link about Aero Classic standard vs HE is https://www.kitplanes.com/cool-and-cooler/
 
I am guessing it is an Aero Classics HE series 8001689, or a comparable Stewart/Meggitt 8432R……both are dual pass, 8 row, 6” core.
 
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