Van's Air Force
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Friend's Oil Temp High
- Thread starter L'Avion
- Start date
That is the same thing I had when I first flew my Rocket. I changed out the Positech for the much more expensive SW and it made no difference. I did a major redo of sealing all the small leaks between the engine and baffling. This helped some. I added louvers on the belly of the cowl. No impact. I took some ideas from the Long-Eze guys (yes I know, plastic airplanes). Look at their oil cooler installation. I hammered and wheeled a small half dish with a flange. I drilled a series of 0.5" holes in the side of the upper cowl just aft of the cooler. I mounted the half dish on the side of the cowl covering half of the drill pattern with the opening facing back. I added an air ramp directing the air down into the cooler on the underside of the upper cowl. Using kinectic energy in additon to static pressure. Voila, success and polished it looked cool. No noticable impact on speed. My primary problem was lack of exit air space. I had a lot of things on the engine and firewall in that area. That could be another approach is to clean up that area if it is crammed. My Rocket has since gone north to Calgary and I am building a 7. I am going to great lengths to avoid this problem again. A local friend is having the same problem with his 7. I never had a problem with the 3 or 4.
Oil coolers
Try looking at this website
www.setrabusa.com
I have had two -110 cooler (10 row) on my RV-6's and they work great never have seen a temp over 185 (even is 100 degree weather). They are better than the Positech or SW for various reason
1. They are cheaper
2. They are thinner and lighter-more air flows through them and less weight hanging off the baffling
3. Install very easily.
4. More clearance between engine and mounts.
5. Mounted on thousands of race vehicles and fork trucks.
I would recommend the -113 (13 rows) for the 6 cyl. My dad has a Rocket with the SW and has oil temp issues as well. Plus his cooler has broken twice in 400 hrs. Too much weight hanging on the baffling.
The only thing you have to watch on these coolers is putting the spacers in between the ears when you mount it. It's the same for the SW as well.
Try looking at this website
www.setrabusa.com
I have had two -110 cooler (10 row) on my RV-6's and they work great never have seen a temp over 185 (even is 100 degree weather). They are better than the Positech or SW for various reason
1. They are cheaper
2. They are thinner and lighter-more air flows through them and less weight hanging off the baffling
3. Install very easily.
4. More clearance between engine and mounts.
5. Mounted on thousands of race vehicles and fork trucks.
I would recommend the -113 (13 rows) for the 6 cyl. My dad has a Rocket with the SW and has oil temp issues as well. Plus his cooler has broken twice in 400 hrs. Too much weight hanging on the baffling.
The only thing you have to watch on these coolers is putting the spacers in between the ears when you mount it. It's the same for the SW as well.
smokyray
Well Known Member
Cool it!
Barney,
Living in the SE USA, I had high oil temps on my -4 and my HR2. Having tried alot of ideas, here's what worked. On my RV4 I moved the cooler to the front mounted underneath the baffle in front of the cyllinder on the LH side with a small deflector scoop on top. I also changed to #8 lines.
On my HR2 I finally angled the SW cooler(on rear left baffle) back 30 degrees, attached it to the engine mount rather than the baffle, changed to #8 lines, moved obstructions from behind it and trimmed my lower cowling lip 2". Using Multi-Vis oil also helps.
Flew my HR2 from ID back to FL yesterday. 1750 NM at 11,500, 2 fuel stops. Cyllinders ran 325F with oil at 195, 10.5 GPH LOP at 195 KTAS. Gotta like it...
Pretty standard for mine...
Smokey
HR2
PS: Aden, I like your Oil Coolers, how did you plumb them?
Barney,
Living in the SE USA, I had high oil temps on my -4 and my HR2. Having tried alot of ideas, here's what worked. On my RV4 I moved the cooler to the front mounted underneath the baffle in front of the cyllinder on the LH side with a small deflector scoop on top. I also changed to #8 lines.
On my HR2 I finally angled the SW cooler(on rear left baffle) back 30 degrees, attached it to the engine mount rather than the baffle, changed to #8 lines, moved obstructions from behind it and trimmed my lower cowling lip 2". Using Multi-Vis oil also helps.
Flew my HR2 from ID back to FL yesterday. 1750 NM at 11,500, 2 fuel stops. Cyllinders ran 325F with oil at 195, 10.5 GPH LOP at 195 KTAS. Gotta like it...
Pretty standard for mine...
Smokey
HR2
PS: Aden, I like your Oil Coolers, how did you plumb them?
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L'Avion
Well Known Member
high oil temp
Smokey, et al.,
We're embarrassed to discover that the air intakes are probably allowing a large amount of air to go unrestricted over and above the air plenum on top of the engine; soooo, we'll add a piece to the plenum forward to catch all the incoming air and direct where it will do some good (other than running up on top of the plenum where it does no good at all).
We found a home based Rocket that had had the same problem - had added an extension on the plenum forward to catch all the incoming air and is cooling nicely.
Perhaps the old story of not being able to see all the trees while standing in the forest is true.
Barney
PS I forgot to add that we did swap the Positech oil cooler out for the better reputed SW, however, we only got 5 degrees cooler oil temps!
Smokey, et al.,
We're embarrassed to discover that the air intakes are probably allowing a large amount of air to go unrestricted over and above the air plenum on top of the engine; soooo, we'll add a piece to the plenum forward to catch all the incoming air and direct where it will do some good (other than running up on top of the plenum where it does no good at all).
We found a home based Rocket that had had the same problem - had added an extension on the plenum forward to catch all the incoming air and is cooling nicely.
Perhaps the old story of not being able to see all the trees while standing in the forest is true.
Barney
PS I forgot to add that we did swap the Positech oil cooler out for the better reputed SW, however, we only got 5 degrees cooler oil temps!
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L'Avion
Well Known Member
high oil temp
Well, we used some "Gorilla" tape to ensure that all inlet air was proceeding into the engine (top) plenum, instead of possibly over the top of it; and, still running hotter than desired 232F.
Maybe someone could chime in here with some ideas: inlet are in sq. inches compared to outflow area in sq. inches, and potential speed loss if one is greater than, lesser than the other, and anything else that might cool this Rocket down???
Thanks,
Barney
PS - Two months ago, we had an RV-4 that was running too hot, moved the oil cooler from the front to the rear - no help; and then added a second oil cooler up front - success. Maybe two oil coolers might help with the Rocket, eh?
Well, we used some "Gorilla" tape to ensure that all inlet air was proceeding into the engine (top) plenum, instead of possibly over the top of it; and, still running hotter than desired 232F.
Maybe someone could chime in here with some ideas: inlet are in sq. inches compared to outflow area in sq. inches, and potential speed loss if one is greater than, lesser than the other, and anything else that might cool this Rocket down???
Thanks,
Barney
PS - Two months ago, we had an RV-4 that was running too hot, moved the oil cooler from the front to the rear - no help; and then added a second oil cooler up front - success. Maybe two oil coolers might help with the Rocket, eh?
frankh
Well Known Member
Two coolers is not the answer
I would go with the Setrab before I ever went with two coolers. It's the coolers we are using that are causing the high temps. They are not flowing the air through them like the Setrab coolers do. They are too thick and heavy.
Smokey- I mounted my hanging off the baffling behind the #4 cylinder. I plumbed them with -8 lines. Here's the interesting part. I used both of the fittings on the top of the engine near the breather. I used a banjo fitting for the 5/8-18 thread fitting by the breather. I used XRP double swivel fittings and stainless steel braided line for the lines. Plumbing was tight but it kept the lines short and the weight down. I know of several other people who have high temp issues and their setups are like everyone elses. They are going towards the Setrab if they can't get the temps down.
I would go with the Setrab before I ever went with two coolers. It's the coolers we are using that are causing the high temps. They are not flowing the air through them like the Setrab coolers do. They are too thick and heavy.
Smokey- I mounted my hanging off the baffling behind the #4 cylinder. I plumbed them with -8 lines. Here's the interesting part. I used both of the fittings on the top of the engine near the breather. I used a banjo fitting for the 5/8-18 thread fitting by the breather. I used XRP double swivel fittings and stainless steel braided line for the lines. Plumbing was tight but it kept the lines short and the weight down. I know of several other people who have high temp issues and their setups are like everyone elses. They are going towards the Setrab if they can't get the temps down.
smokyray
Well Known Member
U Da Man!!!
Thanks Aden, I am ordering a 13 row Setrab cooler tomorrow. Even though mine runs within limits now, my Rocket climb oil temps this summer got warmer than I like. One great thing about Lycomings, they are tough. I towed Banners in my youth and our Scouts would run 210-225 all day long, 1500 hours worth.
An oil engineer once told me oil starts breaking down into carbon at 275F. Aeroshell 15W50 supposedly has enough synthetic in it to lubricate up to 300F. That doesn't mean I want my Rocket to run that hot
Thanks!
Smokey
Thanks Aden, I am ordering a 13 row Setrab cooler tomorrow. Even though mine runs within limits now, my Rocket climb oil temps this summer got warmer than I like. One great thing about Lycomings, they are tough. I towed Banners in my youth and our Scouts would run 210-225 all day long, 1500 hours worth.
An oil engineer once told me oil starts breaking down into carbon at 275F. Aeroshell 15W50 supposedly has enough synthetic in it to lubricate up to 300F. That doesn't mean I want my Rocket to run that hot
Thanks!
Smokey
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Oil cooler
Smokey-let me know if you need some pics. I can try and get some from the guy that bought my RV-6. I basically mounted the thing right off the back of the baffling and I built a "box" out of .063 alum angle so the cooler fit right into it. I had 1/8 angles at the top corners that the mouting bolts and spacers went through. With the cooler mounted in the box and angles it was totally supported. The way the Setrab is designed it lends itself to be mounted in this fashion. The SW hang off the baffling from their mounting flanges. This is why my Dad's cooler always broke. He is thinking about taking the wings off of it and taking her home. We will rebuild the baffling with new cooler, new wheel pants and landing gear leg fairing with all new intersetion fairings. Probably will redo the panel as well with the newer style GPS docks. The wing leading edges also need painting again from going to fast
Smokey-let me know if you need some pics. I can try and get some from the guy that bought my RV-6. I basically mounted the thing right off the back of the baffling and I built a "box" out of .063 alum angle so the cooler fit right into it. I had 1/8 angles at the top corners that the mouting bolts and spacers went through. With the cooler mounted in the box and angles it was totally supported. The way the Setrab is designed it lends itself to be mounted in this fashion. The SW hang off the baffling from their mounting flanges. This is why my Dad's cooler always broke. He is thinking about taking the wings off of it and taking her home. We will rebuild the baffling with new cooler, new wheel pants and landing gear leg fairing with all new intersetion fairings. Probably will redo the panel as well with the newer style GPS docks. The wing leading edges also need painting again from going to fast
L'Avion
Well Known Member
Effects of rpm on oil temp
Being unaware of what might be advisable for a Rocket: This past Sunday we flew a 4-ship involving some pitch-outs & rejoins, followed by some pretty intense trail (4.1 G's); lead was an Extra (lotta power), 2 & 3 were RV-4's (1 IO-360, 1 O-360), 4 was an IO-540 Rocket. We in the RV-4's used 2350 rpm and whatever it took on the throttle to follow, & we ran okay oil temps - 4 got hot (we are unaware of his power settings).
Rocket jockies, where might you set your power to follow in a like situation?
All suggestions and/or ideas will be most gratefully appreciated.
Thanks,
Barney
Being unaware of what might be advisable for a Rocket: This past Sunday we flew a 4-ship involving some pitch-outs & rejoins, followed by some pretty intense trail (4.1 G's); lead was an Extra (lotta power), 2 & 3 were RV-4's (1 IO-360, 1 O-360), 4 was an IO-540 Rocket. We in the RV-4's used 2350 rpm and whatever it took on the throttle to follow, & we ran okay oil temps - 4 got hot (we are unaware of his power settings).
Rocket jockies, where might you set your power to follow in a like situation?
All suggestions and/or ideas will be most gratefully appreciated.
Thanks,
Barney
Based on flight test results I gathered on a few certified powerplant installations, before considering changing oil cooler I would try to optimize the followings:
- Oil cooler upstream cooling air spillage (just on that item alone I was able on one already good installation to reduce Vy climb corrected oil temp by 16 F and Vy climb corrected CHTs by 5 F),
- Re-thing the design of the oil cooler cooling air inlet to Max static pressure recovery (proper free stream air inlet design, proper diffusing to max pressure recovery, no sharp air flow turns - air has a mindset of its own, it doesn't follow the arrows painted on the ducts !); Never put any cooling device into the free stream you will "choke" it at the higher airspeeds - A rule of thumb is no higher than 20 mph for the cooling air across any non-aero coolers and 60 mph across a high-tech aerospace cooler.
- Bring the oil cooler cooling air exhaust closer to the cowling cooling air exit aperture by relocating the cooler or using a duct (to max the cooling air flow [therefore cooling capacity] through any cooling device one needs to max the delta STATIC PRESSURE accross the latter; Once the upstream portion has been optimized, the cooler cooling air exit needs to "see" the lowest ambiant static pressure; That is normally close to the cowling cooling air outlet; On one installation I measured an ambiant pressure in the bottom cowl area that was in excess of about half of the free stream dynamic pressure over the ambiant static pressure at the cowling cooling air outlet, so a substantial gain in delta pressure can be made there).
- Oil cooler upstream cooling air spillage (just on that item alone I was able on one already good installation to reduce Vy climb corrected oil temp by 16 F and Vy climb corrected CHTs by 5 F),
- Re-thing the design of the oil cooler cooling air inlet to Max static pressure recovery (proper free stream air inlet design, proper diffusing to max pressure recovery, no sharp air flow turns - air has a mindset of its own, it doesn't follow the arrows painted on the ducts !); Never put any cooling device into the free stream you will "choke" it at the higher airspeeds - A rule of thumb is no higher than 20 mph for the cooling air across any non-aero coolers and 60 mph across a high-tech aerospace cooler.
- Bring the oil cooler cooling air exhaust closer to the cowling cooling air exit aperture by relocating the cooler or using a duct (to max the cooling air flow [therefore cooling capacity] through any cooling device one needs to max the delta STATIC PRESSURE accross the latter; Once the upstream portion has been optimized, the cooler cooling air exit needs to "see" the lowest ambiant static pressure; That is normally close to the cowling cooling air outlet; On one installation I measured an ambiant pressure in the bottom cowl area that was in excess of about half of the free stream dynamic pressure over the ambiant static pressure at the cowling cooling air outlet, so a substantial gain in delta pressure can be made there).
smokyray
Well Known Member
Great Idea...
Jet/Barney/Aden,
My Rocket's oil temp will hover around 210 doing acro at 2500' on a 90 degree day at 23 squared. I am more concerned about CHT's and mine run nice and cool, even in climb. Dog fighting and slower, higher AOA events (including landing) oil temp will steadily climb to 225, Cruise at 8500', 185. One thing I have found is when my NACA ducts on the fuselage are blowing high volumes of air into the cockpit, temps are cool. At higher AOA, less airflow through the vents, warmer temps under the hood. Maybe I should build a duct from the back of the cooler to the lower cowl...
Smokey
HR2
I flew my RV4 for 13 years in the SE USA and moved my oil cooler 3 times before I figured through trial and error what you just explained, thanks
Jet/Barney/Aden,
My Rocket's oil temp will hover around 210 doing acro at 2500' on a 90 degree day at 23 squared. I am more concerned about CHT's and mine run nice and cool, even in climb. Dog fighting and slower, higher AOA events (including landing) oil temp will steadily climb to 225, Cruise at 8500', 185. One thing I have found is when my NACA ducts on the fuselage are blowing high volumes of air into the cockpit, temps are cool. At higher AOA, less airflow through the vents, warmer temps under the hood. Maybe I should build a duct from the back of the cooler to the lower cowl...
Smokey
HR2
I flew my RV4 for 13 years in the SE USA and moved my oil cooler 3 times before I figured through trial and error what you just explained, thanks
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F.Y.I. ............ http://www.setrabusa.com/oilcoolers.htm
Capflyer
Well Known Member
My oil temps using the standard Van's supplied Niagara oil cooler were running up to 235deg on climb-out and around 218 in cruise. At 220 my prop governor would not work properly so I had to find a solution. At Oshkosh I spoke with Pacific Oil Coolers and he suggested going with a Stewart Warner 8432R which is a dual core oil cooler just slightly larger than the Niagara. Some specs are below.
He said that my temps would drop 20% using this cooler. Being skeptical but desperate then $585 later and some minor modifications to my baffle mount it has worked very well. My oil temps are now sitting around 175deg in cruise and on a hot day climb out never get over 205. The biggest problem I had was that so much air was going through it right over my #4 cyl that I had to put a small air plate to divert the air between the cylinder and oil cooler. Lowered my CHT and only affect the oil cooler by 5deg.
SW 8432R
Single air pass, Two oil pass.
Core:
8 oil fin channels, flow length 5.64".
9 air fin channels, flow length 3.22".
Stack height 4.34"
Collectors: Sheet metal with welded extrusion ports
Approximate unit weight 3.8 Lbs
By the way, I'm getting ready to post the Niagara for sale. Nothing wrong with it but just didn't work for my installation. Anyone here interested?
He said that my temps would drop 20% using this cooler. Being skeptical but desperate then $585 later and some minor modifications to my baffle mount it has worked very well. My oil temps are now sitting around 175deg in cruise and on a hot day climb out never get over 205. The biggest problem I had was that so much air was going through it right over my #4 cyl that I had to put a small air plate to divert the air between the cylinder and oil cooler. Lowered my CHT and only affect the oil cooler by 5deg.
SW 8432R
Single air pass, Two oil pass.
Core:
8 oil fin channels, flow length 5.64".
9 air fin channels, flow length 3.22".
Stack height 4.34"
Collectors: Sheet metal with welded extrusion ports
Approximate unit weight 3.8 Lbs
By the way, I'm getting ready to post the Niagara for sale. Nothing wrong with it but just didn't work for my installation. Anyone here interested?
celstar
Well Known Member
air plate install photo?
Would you have a photo of the air plate you installed? I would like to see your instalation
The biggest problem I had was that so much air was going through it right over my #4 cyl that I had to put a small air plate to divert the air between the cylinder and oil cooler. Lowered my CHT and only affect the oil cooler by 5degSW 8432R
Single air pass, Two oil pass.
Core:
8 oil fin channels, flow length 5.64".
9 air fin channels, flow length 3.22".
Stack height 4.34"
Collectors: Sheet metal with welded extrusion ports
Approximate unit weight 3.8 Lbs
By the way, I'm getting ready to post the Niagara for sale. Nothing wrong with it but just didn't work for my installation. Anyone here interested?
Would you have a photo of the air plate you installed? I would like to see your instalation
Capflyer
Well Known Member
It's under my plenum and I didn't take a picture. It was very simple though....just used a rectangular piece of aluminum the width of the oil cooler opening in the baffle and about 4" high and RTV'd it to the small ledge at the base of the oil cooler laying at about a 45deg angle resting on the #4 cyl. It rises about 1" over the top of the cylinder. The way it is in there is kind of wedged so it cannot move around. It's been there now for about 10 hrs and I'll check it in about another 10. Removing the plenum is a chore.
This was initially a test piece so didn't do too much to secure it permanently. It has worked well so will need to find a way to mount it for good.
swaneymj
Active Member
Smokey, the SW cooler for the Rocket is the 10611R. At least that was the recommendation from the F1 group. But, as you said, it's $$$$. The Spruce price is already $20 higher than I paid 6 months ago. I'm not flying yet, so it remains to be seen how well it will work.
Mark S.
Mark S.
Oil Cooler Picture
Smokyray, I have Aden Rich's RV6 and have a decent pic of how it's (the cetrab) is mounted. I would post it here for you but I don't know how. If you want my picture sent me your email address. (to [email protected]) This cooler works too good. I have a friend with an RV4/fresh engine and plenam set up. He has cooling issue's, trying different coolers/plumbing combo,s. He, picking up his cetrab within the next couple of days. I never have cooling problems even in the most severe conditions. (350 hrs)
Smokyray, I have Aden Rich's RV6 and have a decent pic of how it's (the cetrab) is mounted. I would post it here for you but I don't know how. If you want my picture sent me your email address. (to [email protected]) This cooler works too good. I have a friend with an RV4/fresh engine and plenam set up. He has cooling issue's, trying different coolers/plumbing combo,s. He, picking up his cetrab within the next couple of days. I never have cooling problems even in the most severe conditions. (350 hrs)
Setrab Installation
This is what the installation looks like. Pretty simple. Note how much room you have. Notice the four angles that box the cooler in. You will also see that I have taken the jog out of the baffle and ran it straight across. There is a nice round ramp that goes down into the cooler cut out in the back of the baffle. It put this in to help direct air into it. Like Doug says, it works almost too good. I think the next one I do will have some type of adjustable door like Van's sells. Hope this helps you out.
This is what the installation looks like. Pretty simple. Note how much room you have. Notice the four angles that box the cooler in. You will also see that I have taken the jog out of the baffle and ran it straight across. There is a nice round ramp that goes down into the cooler cut out in the back of the baffle. It put this in to help direct air into it. Like Doug says, it works almost too good. I think the next one I do will have some type of adjustable door like Van's sells. Hope this helps you out.
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