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Jimmy Young
Joined: 24 Nov 2007
Posts: 182
Location: Missouri City, TX
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 Posted: Sat Jul 27, 2013 6:25 pm Post subject: Carb ice, or vapor lock? |
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Don't know if many folks are still monitoring this list, but if so I've got a question.
Two weekends ago, I flew my Zenith 750, powered by a Cont. C-90, from Houston to Arlington TX. I arrived at 10 am, had it topped off and parked it on the ramp. Came back at 3 pm to depart. It was 102 degrees, and dew point approx. 65 degrees. The plane had been parked outside in the sun for 5 hrs. Took off and climbed to 2500' msl and was running at around 2350 rpm. Decided to climb up to 4000' to get in some cooler air.
About 12 minutes into the flight, the engine began to stumble and sputter, losing rpm & power enough that I prepared for an off-field landing. Had a nice site picked and made, and began to pump the throttle to see if the accelerator pump could get some fuel going. Helped a little, but continued to stumble for the next 15 minutes. I was able to maintain altitude and made it to another airport about 11 miles away. My CHT's were climbing & peaked around 410 degrees, even though I could only maintain 2000 - 2200 rpm. They normally stay between 335 & 360 when running 2350 rpm. My EGT's were climbing as well. This indicates to me that I was running lean, if I am correct. I do have a mixture control, but I leave it on full rich all the time and only use it to kill the engine at the end of a flight. Just about the time I had that airport made, the engine began to run normal & all temps returned to normal. I landed and began to try & figure out what had happened.
My first mistake was, I never tried to pull my carb heat when the problem first showed up. I f I had used my carb heat, I may have found the problem was carb ice but at the time, I was more focused on landing off-field. I know it is possible to develop carb ice in any weather, but after a year of flying this plane over 200 hrs it has never stumbled once. This was the hottest weather I had ever flown the plane in. I sumped the gascolator and all the tank sumps, no evidence of water. I pulled the gascolator off and checked the fuel screen, it was clean & no debri was in the bowl. I ended up spending the night in Dallas after taking it back up that evening for a 20 minute full-power flight around the pattern, during which time it ran perfect. Next morning, I departed for Houston and the engine ran fine all the way home.
I began to suspect the possibility of vapor lock. I've got an ACS metal gascolator on the firewall, located low. It has no heat shield or blast tube cooling. From the gascolator to the MA3SPA carb, I've got a SS braided 3/8" fuel line with firesleeve. I was running straight 100 LL fuel.
Last weekend I had an annual done on the plane. We checked the 2 screens on the carb, both were clean. Compression testing showed 79/80, 79/80, 78/80, 78/80. The engine was completely rebuilt in 2011 and had a total of 205 hrs of perfect performance prior to this incident. I discussed it with my A&P and he suggested either carb ice or vapor lock.
My question is, based on the high ambient temps, is carb ice a realistic possibility, or is vapor lock the more likely cause? I have flown in much more carb ice-prone WX over the past year than that particular day, and have never experienced it. I have since wrapped my gascolator with a foil backed fiberglass insulated blanket as a precaution. Any thoughts from more experienced pilots would be appreciated.
Regards & thanks -
Jimmy Young
Houston TX
Zenith CH750, Cont. C-90
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Tommy Walker
Joined: 12 Jan 2006
Posts: 442
Location: Anniston, AL 36207
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| Posted: Sat Jul 27, 2013 6:33 pm Post subject: Carb ice, or vapor lock? |
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Very interesting Jimmy. I would like to hear others reply. I'm still trying to get my O200 Kitfox finished.
As you know I built two 701s.
Tommy,
Sent from my Xoom Tablet On Jul 27, 2013 9:26 PM, "Jimmy Young" <jdy100(at)comcast.net (jdy100(at)comcast.net)> wrote:[quote] --> Continental-List message posted by: "Jimmy Young" <jdy100(at)comcast.net (jdy100(at)comcast.net)>
Don't know if many folks are still monitoring this list, but if so I've got a question.
Two weekends ago, I flew my Zenith 750, powered by a Cont. C-90, from Houston to Arlington TX. I arrived at 10 am, had it topped off and parked it on the ramp. Came back at 3 pm to depart. It was 102 degrees, and dew point approx. 65 degrees. The plane had been parked outside in the sun for 5 hrs. Took off and climbed to 2500' msl and was running at around 2350 rpm. Decided to climb up to 4000' to get in some cooler air.
About 12 minutes into the flight, the engine began to stumble and sputter, losing rpm & power enough that I prepared for an off-field landing. Had a nice site picked and made, and began to pump the throttle to see if the accelerator pump could get some fuel going. Helped a little, but continued to stumble for the next 15 minutes. I was able to maintain altitude and made it to another airport about 11 miles away. My CHT's were climbing & peaked around 410 degrees, even though I could only maintain 2000 - 2200 rpm. They normally stay between 335 & 360 when running 2350 rpm. My EGT's were climbing as well. This indicates to me that I was running lean, if I am correct. I do have a mixture control, but I leave it on full rich all the time and only use it to kill the engine at the end of a flight. Just about the time I had that airport made, the engine began to run normal & all temps returned to normal. I landed and began to try & figure out what had happened.
My first mistake was, I never tried to pull my carb heat when the problem first showed up. I f I had used my carb heat, I may have found the problem was carb ice but at the time, I was more focused on landing off-field. I know it is possible to develop carb ice in any weather, but after a year of flying this plane over 200 hrs it has never stumbled once. This was the hottest weather I had ever flown the plane in. I sumped the gascolator and all the tank sumps, no evidence of water. I pulled the gascolator off and checked the fuel screen, it was clean & no debri was in the bowl. I ended up spending the night in Dallas after taking it back up that evening for a 20 minute full-power flight around the pattern, during which time it ran perfect. Next morning, I departed for Houston and the engine ran fine all the way home.
I began to suspect the possibility of vapor lock. I've got an ACS metal gascolator on the firewall, located low. It has no heat shield or blast tube cooling. From the gascolator to the MA3SPA carb, I've got a SS braided 3/8" fuel line with firesleeve. I was running straight 100 LL fuel.
Last weekend I had an annual done on the plane. We checked the 2 screens on the carb, both were clean. Compression testing showed 79/80, 79/80, 78/80, 78/80. The engine was completely rebuilt in 2011 and had a total of 205 hrs of perfect performance prior to this incident. I discussed it with my A&P and he suggested either carb ice or vapor lock.
My question is, based on the high ambient temps, is carb ice a realistic possibility, or is vapor lock the more likely cause? I have flown in much more carb ice-prone WX over the past year than that particular day, and have never experienced it. I have since wrapped my gascolator with a foil backed fiberglass insulated blanket as a precaution. Any thoughts from more experienced pilots would be appreciated.
Regards & thanks -
Jimmy Young
Houston TX
Zenith CH750, Cont. C-90
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Tommy Walker
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gyoung
Joined: 09 Jan 2006
Posts: 211
Location: Republic of Texas
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| Posted: Sat Jul 27, 2013 7:13 pm Post subject: Carb ice, or vapor lock? |
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I'm based at Hooks in Houston but back in the late 70's I had a Taylorcraft with an A-65 based at Clover Field (now Pearland Intergalactic). Returning from a run to the beach near Matagorda Island I had a similar experience. It was a hot summer day with high humidity like we've had this week. While I did pull carb heat I didn't leave it on long enough. With the power continuing to drop I managed to limp into Lake Jackson and had the engine stop on the runway. By the time I could get some tools to remove the cowling the ice had evaporated and there was no evidence of other problems. I started up and flew home without problems. That was the only time it's ever happened to me. The A & C-series are known for susceptibility to carb ice and I learned afterward that it's possible even on hot days. I would not discount carb ice. I fly behind an IO-550B now so don't have the issue but I'm restoring an L-2 and will need to contend with it again when that is flying.
Greg Young
--
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jim.baker(at)windstream.n
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| Posted: Sat Jul 27, 2013 8:14 pm Post subject: Carb ice, or vapor lock? |
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When ice accumulates, that richens the mixture, not leans it. EGT and CHT would decrease.
http://www.stinsonclub.org/newBB3/viewtopic.php?f=4&t=215
http://flighttraining.aopa.org/students/presolo/skills/carbicing.html
^^^
Each time a normally aspirated, four-cycle engine (which describes the engines in most trainers and simple four-place aircraft) completes two crankshaft revolutions, it draws a volume of air equal to the engine's displacement (less small losses because of throttle position and system friction) through the carburetor. Given a constant throttle position, this volume essentially remains the same whether the carburetor is wide open or clogged with ice.
If the carburetor venturi is constricted because of ice, the velocity of the flow must increase because the amount of air flowing to the cylinders is constant. This increase in velocity is much more significant than the small decrease in mass flow caused by the restriction in the venturi because of ice.
An increase in velocity, Bernoulli says, will cause a further decrease in static pressure within the venturi, which means the ambient static pressure acting on the fuel in the float bowl will push more fuel through the metering jet, resulting in a richer mixture.
***
If your EGTs and CHTs went up, I'd look for another cause.
Subject: Carb ice, or vapor lock?
From: "Jimmy Young" <jdy100(at)comcast.net>
Date sent: Sat, 27 Jul 2013 19:25:59 -0700
To: continental-list(at)matronics.com
Send reply to: continental-list(at)matronics.com
> --> Continental-List message posted by: "Jimmy Young" <jdy100(at)comcast.net>
>
> Don't know if many folks are still monitoring this list, but if so I've got a question.
>
> Two weekends ago, I flew my Zenith 750, powered by a Cont. C-90, from Houston to Arlington TX. I arrived at 10 am, had it topped off and parked it on the ramp. Came back at 3 pm to depart. It was 102 degrees, and dew point approx. 65 degrees. The plane had been parked outside in the sun for 5 hrs. Took off and climbed to 2500' msl and was running at around 2350 rpm. Decided to climb up to 4000' to get in some cooler air.
>
> About 12 minutes into the flight, the engine began to stumble and sputter, losing rpm & power enough that I prepared for an off-field landing. Had a nice site picked and made, and began to pump the throttle to see if the accelerator pump could get some fuel going. Helped a little, but continued to stumble for the next 15 minutes. I was able to maintain altitude and made it to another airport about 11 miles away. My CHT's were climbing & peaked around 410 degrees, even though I could only maintain 2000 - 2200 rpm. They normally stay between 335 & 360 when running 2350 rpm. My EGT's were climbing as well. This indicates to me that I was running lean, if I am correct. I do have a mixture control, but I leave it on full rich all the time and only use it to kill the engine at the end of a flight. Just about the time I had that airport made, the engine began to run normal & all temps returned to normal. I landed and began to try & figure out what had happened.
>
> My first mistake was, I never tried to pull my carb heat when the problem first showed up. I f I had used my carb heat, I may have found the problem was carb ice but at the time, I was more focused on landing off-field. I know it is possible to develop carb ice in any weather, but after a year of flying this plane over 200 hrs it has never stumbled once. This was the hottest weather I had ever flown the plane in. I sumped the gascolator and all the tank sumps, no evidence of water. I pulled the gascolator off and checked the fuel screen, it was clean & no debri was in the bowl. I ended up spending the night in Dallas after taking it back up that evening for a 20 minute full-power flight around the pattern, during which time it ran perfect. Next morning, I departed for Houston and the engine ran fine all the way home.
>
> I began to suspect the possibility of vapor lock. I've got an ACS metal gascolator on the firewall, located low. It has no heat shield or blast tube cooling. From the gascolator to the MA3SPA carb, I've got a SS braided 3/8" fuel line with firesleeve. I was running straight 100 LL fuel.
>
> Last weekend I had an annual done on the plane. We checked the 2 screens on the carb, both were clean. Compression testing showed 79/80, 79/80, 78/80, 78/80. The engine was completely rebuilt in 2011 and had a total of 205 hrs of perfect performance prior to this incident. I discussed it with my A&P and he suggested either carb ice or vapor lock.
>
> My question is, based on the high ambient temps, is carb ice a realistic possibility, or is vapor lock the more likely cause? I have flown in much more carb ice-prone WX over the past year than that particular day, and have never experienced it. I have since wrapped my gascolator with a foil backed fiberglass insulated blanket as a precaution. Any thoughts from more experienced pilots would be appreciated.
>
> Regards & thanks -
>
> Jimmy Young
> Houston TX
> Zenith CH750, Cont. C-90
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=405454#405454
>
>
>
>
>
>
>
>
>
>
Jim Baker
Elmore City, OK
580.788.2779 home
405.426.5377 cell
[quote][b]
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BARRY CHECK 6
Joined: 15 Mar 2011
Posts: 738
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| Posted: Sun Jul 28, 2013 2:04 pm Post subject: Carb ice, or vapor lock? |
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Hi Jim:
There are quite a few questions and comments I have to go through:
1 - Did you check your Spark Plugs?
2 - Did you check your Timing? <--- Major issue after an Annual.
3 - WHY DID YOU NOT LEAN? <--- You should be leaning ALL the time. Lean avery aggressively while taxing - So much so - THAT - If you forget to go full rich on take-off the engine will die. You CANNOT hurt the engine and it will prevent lead fouling of the plugs and save you a little taxi gas.
4 - Keeping with the leaning subject - As you altitude increases you will be running way too rich. This could cause a reduction in HP as well as carbon & lead fouling. Extra rich also lowers the temp in the carb which will increase your possibilities of Carb Ice.
5 - I am not a fan of Gascolators - Just way too many issues with them - I do believe very strongly in - IN LINE fuel filters. BUT! I doubt it the Gascolator was the culprit.
6 - ALL your fuel lines should be heat shielded... Well, as much as physically possible.
7 - Vapor Lock - Is easy to prevent. It starts with fuel system design What size fuel line are you using? What is the fuel line made from? How do you have the fuel line routed? How is the overall cooling under the cowl?
8 - From you statement of: "They normally stay between 335 & 360 when running 2350 rpm. My EGT's were climbing as well. This indicates to me that I was running lean, if I am correct." Well you are correct. A CHT of 410 F is above normal IF you compare it to past operations. What were the EGT readings at the time? I'd bet below 1400 F probably more like 1320 F. SOoooo what would cause leaning? NOT VAPOR LOCK! With vapor lock you loose gas flow and the EGT & CHT goes DOWN. NOT CARB ICE! With carb ice you loose fuel flow and EGT & CHT goes DOWN. If CHT goes Down and EGT goes Up --- LQQK at fouled plugs or poor spark. If RPM cannot be maintained and CHT goes Up ---LQQK at AIR LEAKS... Carb, Intake Tubes.
9 - You did not mention OIL TEMPS?
OK - Enough for now. Let's hear back from you on these basic checks.
Barry
[quote][b]
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Jimmy Young
Joined: 24 Nov 2007
Posts: 182
Location: Missouri City, TX
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| Posted: Sun Jul 28, 2013 4:08 pm Post subject: Re: Carb ice, or vapor lock? |
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Barry wrote:
| Quote: | | 1 - Did you check your Spark Plugs? |
Yes. they looked good, tannish to greyish in color, not fouled.
| Quote: | | 2 - Did you check your Timing? |
Did that at annual. 26 & 28 degrees, same as first flight 1 year previous.
| Quote: | | 3 - WHY DID YOU NOT LEAN? |
No good reason, other than I've been advised that unless I'm flying above 5000' regularly, I don't need to. I usually fly at less than 3000' msl most of the time.
| Quote: | | 5 - I am not a fan of Gascolators - Just way too many issues with them - I do�believe�very strongly in - IN LINE fuel filters. �BUT! �I doubt it the Gascolator was the�culprit. |
Ok, but what then separates water from your fuel?
| Quote: | | 6 - ALL your fuel lines should be heat shielded... �Well, as much as physically possible.� |
| Quote: | | 7 - Vapor Lock - Is easy to prevent. �It starts with fuel system�design� �What size fuel line are you using? �What is the fuel line made from? �How do you have the fuel line routed? How is the overall cooling under the cowl? |
Lines are 3/8" Aeroquip rubber hose with AN socketless fittings, except FWF it's 3/8" Aeroquip SS braided hose with firesleeve. They are routed straight from the wing tanks to a tee, to a shut off valve, to the FW bulkhead pass-thru, to the gascolator, and on to the carb. Pretty standard and straight-forward. You ask "how is the overall cooling under the cowl? I've got temp strips on the mags and the firewall. They have topped out between 160 & 180 degrees. Don't really know how one could keep that area cool, as it's purpose is to exhaust engine heat. I have considered running blast tubes to my mags.
| Quote: | | 8 - From you statement of: "They normally stay between 335 & 360 when running 2350 rpm. My EGT's were climbing as well. This indicates to me that I was running lean, if I am correct." �Well you are correct. �A CHT of 410 F is above normal IF you�compare�it to past operations. What were the EGT readings at the time? �I'd bet below 1400 F�probably�more like 1320 F. �SOoooo what would cause leaning? �NOT VAPOR LOCK! �With vapor lock you loose gas flow and the EGT & CHT goes DOWN. �NOT CARB ICE! �With carb ice you loose fuel flow and EGT & CHT goes DOWN. �If CHT goes Down and EGT goes Up --- LQQK at fouled plugs or poor spark. �If RPM cannot be maintained and CHT goes Up ---LQQK at AIR LEAKS... �Carb, Intake Tubes. � |
My egt's each register a little different temps in cruise, but they always stay consistent. I had my hands full flying the plane so I wasn't taking notes, but I do recall when the cht alarm light went off I noticed the highest egt was 1440 or so which is about 75-100 degrees higher than it would normally be. So, I had both higher cht's and egt's occuring at the same time my engine was stumbling & performing poorly. These higher CHT & EGT's may have been partly caused by my having a pitch-up attitude & slow airspeed, trying to hold altitude at low power output for an extended period of time while I was nursing my way to the other airport. This would have obviously reduced the volume of cooling air to the engine. I've noticed when doing slow flight at 1800 & 1900 rpm, my cht's will get up in the mid 300's similar to full cruise due to the same lack of cooling air volume.
I've got a question for you on this section. You said "With vapor lock, you loose gas flow and the cht & egt go down." Seems to me the opposite would occur, since you'd have the same air volume and less gas, thus a leaned out condition. What am I missing there?
| Quote: | | 9 - You did not mention OIL TEMPS? |
They never exceeded 210. On a hot summer day they will settle in between 200 & 210 at cruise. In the Texas winter, O/T runs 180 -195. I do not have an oil cooler.
I appreciate the input, & please let me know what any or all of you think on these comments. I'm still leaning towards vapor lock. Yesterday, I made a foil-faced insulation blanket and wrapped my gascolator with it. Tied it off with cable ties.
Jimmy Y
Houston
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brianrobertwood(at)gmail.
Guest
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| Posted: Mon Jul 29, 2013 3:25 am Post subject: Carb ice, or vapor lock? |
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Five hours in the Texas sun, I would put money on the vapor lock theory.
Your engine compartment was thoroughly heat-soaked.
Brian in Brazil
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BARRY CHECK 6
Joined: 15 Mar 2011
Posts: 738
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| Posted: Mon Jul 29, 2013 4:29 am Post subject: Carb ice, or vapor lock? |
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Jimmy:
I removed the responses that were answered and no longer pose a question to the final result.  Please read on.
Barry
On Sun, Jul 28, 2013 at 8:08 PM, Jimmy Young <jdy100(at)comcast.net (jdy100(at)comcast.net)> wrote:
| Quote: | --> Continental-List message posted by: "Jimmy Young" <jdy100(at)comcast.net (jdy100(at)comcast.net)>
Barry wrote:
| Quote: | 3 - WHY DID YOU NOT LEAN?
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No good reason, other than I've been advised that unless I'm flying above 5000' regularly, I don't need to. I usually fly at less than 3000' msl most of the time.
[Barry] - The information you were given, which was also given in part to most of us as new pilots is incorrect. Â The basic rule was 'lean at and above 3000 feet'. Â What was missing from the statement or misunderstood due to your limited experience at the time was 3000 feet Density Altitude. Â This makes it a almost LEAN all the time, since even my airport on a hot day is 2000 Ft DA. Â Also consider that as a student most of the planes DO NOT have EGT & CHT gauges. Â AND it is much easier to make a simple statement than try to explain to a student EGT, CHT and Leaning. Â Also plug fouling is a major concern, so the rule has changed to Lean All The Time. Â If one gets into the good habit of leaning all the time the action will become as natural as appling power for take-off.
|
Â
| Quote: | > 5 - I am not a fan of Gascolators - Just way too many issues with them - I do�believe�very strongly in - IN LINE fuel filters. �BUT! �I doubt it the Gascolator was the�culprit.
Ok, but what then separates water from your fuel?
|
[Barry] - Jimmy, this is a huge debatable topic which will never be solved until the Gascolator is made CLEAR, the water dyed and a camera setup to film the fuel/water action. Â The first rule is: Do not put water into the system. Â I think this is done very well by the fuel companies. Â The gascolator does not function as well as it is given credit for. Â Yes, you will see water collect in it from time to time but, that is more because of its location that the action of its function. Â IF it was such a great item then why isn't it required by the FAA on EVERY plane? Â ANYWAY! ! ! ... Â If you got it ... Â Use it ... Â Drain it ... And question: Where is the water coming from?
| Quote: |
| Quote: | 7 - Vapor Lock - Is easy to prevent. �It starts with fuel system�design� �What size fuel line are you using? �What is the fuel line made from? �How do you have the fuel line routed? How is the overall cooling under the cowl?
|
Lines are 3/8" Aeroquip rubber hose with AN socketless fittings, except FWF it's 3/8" Aeroquip SS braided hose with firesleeve. They are routed straight from the wing tanks to a tee, to a shut off valve, to the FW bulkhead pass-thru, to the gascolator, and on to the carb. Pretty standard and straight-forward. You ask "how is the overall cooling under the cowl? I've got temp strips on the mags and the firewall. They have topped out between 160 & 180 degrees. Don't really know how one could keep that area cool, as it's purpose is to exhaust engine heat. I have considered running blast tubes to my mags.
|
[Barry] - EXCELLENT! Â Years ago I hooked up a Lab Digital Thermometer to various points under the cowl; I got the exact same readings as you are seeing. Â A blast tube for the Mags is a good idea as wells as for the plastic COUPLING between the vacuum pump and engine. Â
| Quote: |
> 8 - From you statement of: "They normally stay between 335 & 360 when running 2350 rpm. My EGT's were climbing as well. This indicates to me that I was running lean, if I am correct." �Well you are correct. �A CHT of 410 F is above normal IF you�compare�it to past operations. What were the EGT readings at the time? �I'd bet below 1400 F�probably�more like 1320 F. �SOoooo what would cause leaning? �NOT VAPOR LOCK! �With vapor lock you loose gas flow and the EGT & CHT goes DOWN. �NOT CARB ICE! �With carb ice you loose fuel flow and EGT & CHT goes DOWN. �If CHT goes Down and EGT goes Up --- LQQK at fouled plugs or poor spark. �If RPM cannot be maintained and CHT goes Up ---LQQK at AIR LEAKS... �Carb, Intake Tubes. �
My egt's each register a little different temps in cruise, but they always stay consistent. I had my hands full flying the plane so I wasn't taking notes, but I do recall when the cht alarm light went off I noticed the highest egt was 1440 or so which is about 75-100 degrees higher than it would normally be. So, I had both higher cht's and egt's occuring at the same time my engine was stumbling & performing poorly. These higher CHT & EGT's may have been partly caused by my having a pitch-up attitude & slow airspeed, trying to hold altitude at low power output for an extended period of time while I was nursing my way to the other airport. This would have obviously reduced the volume of cooling air to the engine. I've noticed when doing slow flight at 1800 & 1900 rpm, my cht's will get up in the mid 300's similar to full cruise due to the same lack of cooling air volume.
I've got a question for you on this section. You said "With vapor lock, you loose gas flow and the cht & egt go down." Seems to me the opposite would occur, since you'd have the same air volume and less gas, thus a leaned out condition. What am I missing there?
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[Barry] - Jimmy, Vapor Lock is another one of those topics that is debatable to infinity. Â To clarify a bit, as your fuel air statement sounds like you are considering there is an AIR/FUEL mixture/ratio - Vapor Lock occurs in fuel lines. Â Your question assumes you can have a PARTIAL Vapor Lock. Â Allowing some fuel to flow. Â I do not believe in a Partial Vapor Lock. Â Either you have it or you don't! Â Think of it this way: Â If you have a Vapor Lock, it is caused by High Temps EXPANDING the vapor pressure of the fuel. Â This vapor bubble requires two things: 1> High Temps, enough to cause fuel expansion to a vapor level within a confined space and 2> A SPACE to trap the vapor bubble. Â This SPACE has to be a Upward or Downward 'U'. It does NOT happen in a straight run. Â SOoooo, if fuel was to trickle by the Vapor Lock Bubble - - - The fuel would COOL the BUBBLE and the Vapor Lock would go away. Â Ergo, you can not have a partial Vapor Lock. Â Either you do or you don't. Â It is like being only slightly pregnant.
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> 9 - You did not mention OIL TEMPS?
They never exceeded 210. On a hot summer day they will settle in between 200 & 210 at cruise. In the Texas winter, O/T runs 180 -195. I do not have an oil cooler.
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[Barry] - WOW! Â TEXAS and NO COOLER! ! ! Â Not even for the BEER?
That is FANTASTIC temps without a cooler. Â Just think how much happier your engine would be with a cooler? Â That is truly a great cooling system you did to the plane. Â People are fighting to get those temps - Another EXCELLENT JOB.
[Barry] - So the question still exists - What caused the loss of power? Â
Wish I was there to LQQK over your system. Â Could you take some pictures or a SLOW MOVING video of the system and email me? Â Maybe something will jump out and bite me.
Talk to you later,
Barry
[quote]
I appreciate the input, & please let me know what any or all of you think on these comments. I'm still leaning towards vapor lock. Yesterday, I made a foil-faced insulation blanket and wrapped my gascolator with it. Tied it off with cable ties.
Jimmy Y
Houston[b]
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