F

Flying Scotsman

Well Known Member
I'm going to open an old can of worms here...I did search through the forums, but a lot of the threads seem to be a little old (maybe my search wasn't very well formulated)...

Starting work on the baffling now, so the question becomes...Van's "stock" oil cooler (I guess it's a Niagara?) vs. maybe a Stewart-Warner. I'm a "keep it as designed" kind of guy, so would like to stick with Van's plans, parts, etc., if possible.

So, a couple of questions...I have a stock, Lycoming IO-360 on an RV-7A. What are people's experience with the stock cooler? If you feel the stock cooler is inadequate, which one did you replace it with, and are the "footprints" the same? (i.e., can you use the same mounting hardware and parts)?

Any help or advice based on real-world experience with the same or similar set-up is very much appreciated. I'm not in to buying pricey parts unless necessary, but if necessary, I have no problem doing so...

TIA!

Steve
 
Stock Oil Cooler

You are going to get different answers, but I can share my experience. I have 185 HP clone with a James cowl, a plenum and the stock oil cooler. I ended up installing an oil cooler shutter to get my temps up enough to take the water out of the oil. I run it closed most of the year, but I do live in Montana.

Hans
 
Van's Niagara has served me well on four ships, all 180 or more horsepower 360s. What seems the big swinger is how well the engine cools itself convectively. Heresay hereabouts from mechs and builders is that ECi jugs run hot, tapered fin ECi jugs run hotter, Lycs are coolest. My experience bears this out. I suggest Van's to start with, and likely you won't have to add capacity with a larger/better(?) cooler unless your engine is a problem to begin with. The current -7 has over 200hp from an O-360 carbed from Lyc jugs flowed by Lycon; it's Niagara cooler has 30% of the fins block year round: summer, 190; winter, 170 degrees and the CHTs are 300 - 380 depending on ambient/power.

A common problem is cracking of the #4 baffle where it is bent to form a flange that receives the cooler. Reinforce this with some angle, not just the extra plate between the baffle and cooler flanges as the instructions show.

John Siebold
 
Stock cooler worked OK for me

I run the stock cooler on my O-360 and rarely see temps over 191. However, when we positioned the cooler on the mounting baffle, we kept it as high as possible to insure that lots of air passed thru it.

IOW, don't tuck it down behind the cylinder.

Note, I fly out of Tucson.
 
Van's stock oil cooler

On my RV7A with 0-360, Catto Prop, stock oil cooler, stock baffling, rarely see temps over 180 even in summer temp. in Indiana. Like Barry mentioned kept it high on the baffling. Now the head temp will get up to 425 on #1 (on hot summer day) if I climb out at 1500-2000 ft. min so I keep the speed up 120 knots no problems.

Squeak
RV7A
 
Same Experience

I have a Superior 0-360 built by Aero Sport Power. Had my first flight the first of September with ambient temps still in the low 90s, and never seen oil temps over 190F. Blocked half of my oil cooler off recenlty because ambient temps are now in the 60s and 70s and only seeing 170 to 180. Suspect I will have to block the entire cooler this winter.

My buddy with a ECI O-360 and Sam James Cowl recently bought a larger oil cooler, as he was struggling to keep his temps down. He might chime in here.
 
I would agree with much of what John says--much depends on your engine/cyl/ignition/cooler location. The Eci cerminil cylinders tend to run hotter than stock steel and if you have either the Eci cam squirters, the piston squirters, and/or electronic ignition you will be introducing more heat into the oil. I have all of the above except the piston oilers on my Eci Titan 0360 and run a bigger cooler--the SW 10599 on my firewall.

It appears that you have a stock Lyc engine as opposed to the Eci or Superior clone so I would bet that, assuming your baffling is tight, the stock cooler or at most the same sized SW 8406R cooler would do fine.

Hope this helps.

Cheers,

db
 
On my IO-360 (ECI) with 9:1 cylinders, my oil temps will be up around 210-215 on a hot day (80-90F). A little higher than I would like but not high enough to make me switch to the SW cooler. If I was starting over however, I would probably go with the SW. Never have to block off any of my cooler though :)

Erich
 
I had the standard Niagra on my RV-6 and mounted it on the firewall to avoid baffle cracking - more prevalent back then. I never had high oil temps with that installation and had to block air through it in the colder months. On my RV-8, I mounted the standard cooler as high as possible on the baffle. I have an ECI EXP360 with 9:1 pistons and one electronic ignition. My oil temps this last summer were running around 215, sometimes a little warmer, even up high with OATs in the high 50's. I installed a SW cooler of the exact same size and my temps droppped 20 degrees. I'll still have to block air through it this winter, but I think you'll need to do that no matter what your installation is.
 
Standard cooler. Usually runs around 190-195 in summer. Mounted high on back baffle #4 cycl/with reinforcing angle. Use the Van's slider damper for winter months. Highest temp I've seen with damper closed is 205 in the winter. It never gets that hot with damper opened in summer.

L.Adamson --- RV6A/ O360 AIA
 
SW style oil cooler

Ive been reading the posts and am about to order the firewall forward package from vans for my 7a. I have an IO-360 Aerosport 180 hp CS with Superior cold air sump and horizontal induction. Is it best to stay with the Stewart Warner seven-tube style cooler or should I maybe go to the IO-360(200hp) that vans offers? Any experience with fit for the larger vs smaller unit. Thanx guys and Merry Christmas all! Keep on keepin' on. gary
 
There is also an Aero Classic 10-row cooler that's about the same external size of the SW 9-row 10599R for literally half the cost. Another RV-7 builder here on the forums, "lostpilot28" recently upgraded to this cooler on his IO-360 RV-7 and is getting about the same results as we are with the SW10599R on the ECI IO-360 RV-8 in my avatar (pics of our oil cooler installation in this thread http://www.vansairforce.com/community/showthread.php?t=65412 )
 
standard is fine

we have a mattituck tmx-io360 180hp with lycoming based cylinders.
the stock oil cooler is just fine, in our case it's actually too efficient.

we are just about to retrofit the van's oil cooler shutter, which would have been much easier to install right from the beginning. but we figured, rather not to block anything for the first few flights since we can always go the other route. but if we glaze the cylinders with too high of an oil temperature it might get expensive. turns out we would have been perfectly fine.

my only complaint about the default oil cooler is the quality of threads and flanges. the first one that we got actually had what turned out as a slightly oval thread, which lead to an aluminum fitting galling up and we had to replace the cooler.

the second was better, however we could only get the npt threads to seal using titeseal in what was about the third attempt. before there would always be small drops of oil (using ez-turn fuel lube initially) at the fittings. never lost much, but enough to not tolerate/leave it.
also you will find the whole discussion about whether to use aluminum or steel fittings heavily debated. we got to the point where we had the steel fittings ordered, but then got the aluminum ones tight, so we opted not to replace them for now (why fix if not broke ;-)

right now, having to retrofit the oil cooler shutter is a pain in various ways.
for one, the shutter needs to be between the cooler and the baffling, mounting it behind the cooler is widely reported as ineffective.
but in the baffling there are rivet heads protruding as well as the oil cooler doubler with the bent-back flanges that have to be made to fit. then there's the question whether we'll possibly need special bolts, one size longer (if we end up having to make a doubler for clearing the rivet heads). which is extra expense and another mail order item from the u.s.

also the actuation is debatable. right now we are leaning towards a short push-pull type cable which remains firewall forward and can be set through the oil dipstick door, with fixed notches. there's also a possibility to just lock the shutter it in one position per season. or making actuation from the cockpit possible, either through some kind of electric servo or yet another firewall pass-through for yet another push-pull cable dedicated to the oil cooler shutter.
what is everybody else doing?
reading very little about the shutter online.
if there's threads it's mostly about alternative oil coolers / not enough cooling, which totally doesn't apply in our case.

one thing that probably helps with cooling in our case (and what we would do again) is the two louvers on the bottom of the cowling.

rgds,
bernie
 
also the actuation is debatable. right now we are leaning towards a short push-pull type cable which remains firewall forward and can be set through the oil dipstick door, with fixed notches. there's also a possibility to just lock the shutter it in one position per season. or making actuation from the cockpit possible, either through some kind of electric servo or yet another firewall pass-through for yet another push-pull cable dedicated to the oil cooler shutter.
what is everybody else doing?
reading very little about the shutter online.
if there's threads it's mostly about alternative oil coolers / not enough cooling, which totally doesn't apply in our case.
Click to expand...

You'll need longer bolts, unless the originals had too many washers to begin with. Washers need to be installed on both sides of the shutter, to prevent the cooler fins or baffles from rubbing. The actuation of the shutter should be very easy to push/pull.

I used the Van's black knob cable, they sell for heat & carb heat. It replaced a somewhat lighter, but flimsier cable from Autozone. Personally, I'd much rather have the option to adjust from the cockpit, than a requirement to be on the ground. Where we fly in the winter, has quite a temperature change. I also have the standard Van's cooler. It's been fine.
Lycoming 0360AIA

L.Adamson --- RV6A
 
Need for the shutter

I thought the oil coolers have a thermostatic controlled valve that opens when the oil temp rises to a set point, closes when too cool. The valve when closed would prevent the oil from going thru the oil cooler, that is, the oil would bypass the finned part of the cooler and go around the perimeter. So why the need for the shutter to block out the cold air when oil may not even be going thru the cooler? I have yet to see one on a O320 powered Skyhawk (OK maybe this is a bad example-we are supposed to make them better).

If there is a need, I'll put one on but not just to add weight. Even when the shutters are fully open the setup would block some air out when air flow capacity is needed on those hot summer climb outs.
 
The early positech coolers had poor cooling performance. They improved their core and now have excellent performance, a more robust build than the others, and a very good price. IMO best bang for the buck on coolers. The old rep of poor cooling performance lives on so it is hard for many to accept these coolers as a good choice.
 
jimbo said:
I thought the oil coolers have a thermostatic controlled valve that opens when the oil temp rises to a set point, closes when too cool. The valve when closed would prevent the oil from going thru the oil cooler, that is, the oil would bypass the finned part of the cooler and go around the perimeter. So why the need for the shutter to block out the cold air when oil may not even be going thru the cooler? I have yet to see one on a O320 powered Skyhawk (OK maybe this is a bad example-we are supposed to make them better).

If there is a need, I'll put one on but not just to add weight. Even when the shutters are fully open the setup would block some air out when air flow capacity is needed on those hot summer climb outs.
Click to expand...

It is not supposed to close enough to block all the oil from going through the cooler.
 
jimbo said:
If there is a need, I'll put one on but not just to add weight. Even when the shutters are fully open the setup would block some air out when air flow capacity is needed on those hot summer climb outs.
Click to expand...

The cooler's fins, takeup quite a bit of the free area, when it comes to square inches. I assume this is thought of, in the shutter design. Never the less, the system worked well on a friends 9A this summer. I didn't get enough air time during the hottest months, due to various non-aviation accidents here and there. But mine did work well through the middle of July, where temps were in the 90's.

L.Adamson --- RV6A
 
jimbo said:
I thought the oil coolers have a thermostatic controlled valve that opens when the oil temp rises to a set point, closes when too cool. The valve when closed would prevent the oil from going thru the oil cooler, that is, the oil would bypass the finned part of the cooler and go around the perimeter.
Click to expand...

There is no valve in the cooler itself. The valve, called a vernatherm, is actually in the engine (oil filter adapter). Even when the vernatherm is completely retracted, a significant amount of oil still circulates thru the cooler at all times the engine is running.
 
x-series

I had been planning on using the X-Series from aviation tech... it is a little more expensive than the vans stock.. I have a IO 360 200 hp.. any thoughts or experience with this one.

1195666637038654112136.jpeg


http://shop.aviationtechproducts.co...FA985DC.qscstrfrnt04?productId=7&categoryId=2
 
I have recently installed a Mocal 7 row HD cooler on a parallel valve (180hp) IO-360 in another homebuilt (One Design), mainly because it was lighter and I could use shorter oil hoses. This is an Aerosport engine built from Lycoming components. So far (about 25 hours) there have been no overheating problems - max OAT around 90?. I re-inforced the back baffle with a piece of 0.050".

Here it is during construction

Pete

image036.jpg
 
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