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Tip: How I ended up mounting the E.I. Fuel Flow Transducer (Red Cube)

Brantel

Well Known Member
Earlier I went as far as completing the install using this method.....

20ksvhd.jpg



But the more I worried about the issues I could dream up on this version like:

1. Cracking of the solid tube over time
2. Pulling fuel through the transducer creating an opportunity to suck air through a bad seal on one of the covers
3. Vapor lock in the line
4. Pulsing of the readings when the boost pump is on

The more I thought about changing it the more I could'nt leave it!

So I decided to move it! Using lots of the tips in the various threads, I came up with this option:

x6kc4i.jpg


This option gave me an opportunity to follow most if not all of the manufacturers rules for installing this thing.

I replaced all the aluminum fittings with steel while I was at it.

I only needed one extra fuel line which I ordered from Don at Airflow Performance. He made me one up with a 45? fitting on one end and coupled with the 45? adaptor fitting in the cube, this works out great!

de0irp.jpg
 
Can't see the last two pictures...

Didn't the direction for the FF cube say to keep it straight for a couple of inches on either side?

Kent
 
Doesn't look like enough slack in the line from the carb to the clamp on the mount, looks like you could just elimate the clamp. I know pictures can be decieving but this is just the way it appears to me.
 
Doesn't look like enough slack in the line from the carb to the clamp on the mount, looks like you could just elimate the clamp. I know pictures can be decieving but this is just the way it appears to me.

Yes pics can be very misleading.....There is plenty of slack. One can move the line around +-1.5" or more in all directions on both sides of the clamp.
 
I dont know Brian - you might need one more bolt to make sure that support bracket doesnt fall off the firewall :D

just yankin your chain. Looks great.

erich
 
I dont know Brian - you might need one more bolt to make sure that support bracket doesnt fall off the firewall :D

just yankin your chain. Looks great.

erich

:D I knew someone would raz me about that... Here is the deal on that: I originally riveted that bracket to the other side and I had to drill out those rivets. Due to access issues, I was less than perfect getting them out so a couple of the holes got a little trashed. Me being lazy, I did not want to remake the bracket and I wanted a couple bolts to go thru the firewall reinforce angle so I just went ahead and bumped all the holes up to #12 and used bolts. Way overkill but it won't fall off! :p
 
I still have a problem....

Pics are all hosted by same site...Try a refresh.

With seeing the pictures. I don't understand but my browser (Iexplorer) show the last too links as broken. I tried putting the address in the explorer directly and they don't work for me. I assume it is something on my end.

http://i42.tinypic.com/de0irp.jpg
http://i40.tinypic.com/x6kc4i.jpg
don't work

http://i44.tinypic.com/20ksvhd.jpg

works.

Hey, I just tried change the i40 to i44 and I now see the picture.
That is also true with the i42 being changed to i44.
http://i44.tinypic.com/de0irp.jpg
http://i44.tinypic.com/x6kc4i.jpg

Now that I see the picture, your installation look the same as mine except the I used longer hose and straight connectors on the red box.

Kent
 
Now that I see the picture, your installation look the same as mine except the I used longer hose and straight connectors on the red box.

Kent

Kent,

Thanks for paving the road! I copied some ideas from other links, must have been yours!
 
Doesn't look like enough slack in the line from the carb to the clamp on the mount, looks like you could just elimate the clamp. I know pictures can be decieving but this is just the way it appears to me.

Walt,

That one be an issue as the engine rotates, thus there is relatively little movement in the center.

Brian,

I do have one issue, and this is something our chapter TI's look for, you should not have a downhill "pouch" in your fuel line after leaving the gascolator. This can hold water and debris which may accumulate over time.

FYI, your first setup is exactly what I've been using for 240 hours. Your issue #3 is right on. I solved that by putting fire sleeve on it like you showed in your picture. Prior to that I was running just aluminum tubing and had four engine stoppages during my Phase I. After having the fire sleeve they have not reoccurred and I tried everything I could think of to get the engine to stop. Typically it took a long, slow glide to get enough heat back there to boil the fuel.

The U isn't subject to stress so there is very little chance it will crack. If this worried you, just support it at the top of the U.
 
Yes Bill, I know most likely it would have been fine...

I do like the idea that most likely this new install will not screw up the readings when the boost pump is on....

I think the risk on the "pouch" is very low in this situation.
 
Critique my Red Cube install

I made a fuel hose to route from the fuel pump to the Red Cube. The other hose from the Red Cube to the carb is a stock one that Vans sell. Routing from the pump to the Red Cube was limited due to engine mount interference. How's this installation look? Thanks!
238a451c83f6efdf1963a48008f604e111987_0721001346.jpg
 
Hi Mike,
Can't see what the fitting is on the hose into the Red Cube inlet but if I were to guess I would say it's a 90 degree elbow.
If it is a 90 degree fitting, my only comment is that that does go against the manufacturer's recommendations.

I know it's tricky. I broke the recommendations too, but my transgression is a 90 degree fitting on the outlet side.
The manufacturer advised me that if you have to have an 90 degree angle fitting it is preferable to have it on the outlet.
They also said that a 45 degree on each side was better than using one straight and one 90.

But even so they said this was about shooting for the ideal setup and the Cube still gives good readings even in less than ideal circumstances.

Also note that the manufacturer advised me that the preference for fittings was: brass best, steel 2nd, aluminium 3rd. I've used steel.
But I guess this is not quite so much of an issue with your static installation. With mine the Cube is 'floating' on the hoses.
 
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The post from the manufacturer's employee on this board seem to suggest a different opinion.....

As far as I know Dynon distributes both the FloScan 201B as well as EI's FT-60.

The FloScan unit is much more sensitive to the angles/fittings entering and exiting the unit. EI's unit does not care. You can run 90 degree fittings in and out of ours without problems.

JPI does not sell EI's FT-60:cool:

Maybe you can get Dynon to trade you for a FT-60?

Good luck!

Matt


You do NOT want to rigid mount the transducer to the motor (any part) using just a fitting. It is a huge safety issue. The fitting could theoretically fatigue and break. You absolutely need to have flexible line on both sides of the Floscan 201B or the EI FT-60 (that Dynon now utilizes).

After manufacturing/supporting flow instruments for a good number of years we have seen that flow transducers accuracy is typically better when mounted after both fuel pumps. They simply seem to prefer to have fuel pushed through them, not pulled through. The truth of it though is that many installation drawings still read as though we were still using the older Floscan 201 transducers. I have seen installs that mount the transducer between the pumps with claimed success. The Floscan units were much more sensitive in regards to mounting location, angles of fittings in and out, and attitude. Our new design will tolerate a lot more. Frankly we don't care if the thing flows straight up, or if you put 90-degree fittings in and out (FT-60 only) of the transducer. Just don't mount it upside down or flowing sharply downhill.



Hope this helps,

Matt Sharp


Hello All!

Your friendly neighborhood EI Tech support rep here!

There are really two issues in regards to EI’s specifications on flow transducer placement.

1. Accuracy of the output of the flow transducer.
2. Safety.

Issue one is pretty basic. After manufacturing flow instruments for a good number of years we have seen that flow transducers accuracy is typically better when mounted after the mechanical fuel pumps. They simply seem to prefer to have fuel pushed through them, not pulled through. The truth of it though is that many installation drawings still read as though we were still using the older Floscan 201 and 231 transducers. I have seen installs that mount the transducer between the pumps with claimed success. The Floscan units were much more sensitive in regards to mounting location, angles of fittings in and out, and attitude. Our new design will tolerate a lot more.

The other more serious issue is in regards to safety. We want to make absolutely sure that the fittings on the transducers never are subjected to conflicting vibration planes. The engine will flex in the motor mounts creating conflicting vibration planes between the engine and the airframe. This is why the “flexible line in” and “flexible line out” is called out so often. This is also why we don’t want the transducer rigid mounted, via a fitting, to a carburetor or fuel pump. A contradicting vibration plane will focus the energy directly to the fitting. It is our sincere concern that with the two conflicting vibration planes here could cause the fitting to fatigue and crack. This would be bad…and we have seen it happen….

On the bright side, we don’t care if the thing flows straight up, or if you put 90-degree fittings in and out of the transducer. Just don’t mount it upside down, flowing sharply downhill, or before the pumps. :eek:

Please let me know if you have any questions or if we may be of any assistance.

Matt Sharp






Hi Mike,
Can't see what the fitting is on the hose into the Red Cube inlet but if I were to guess I would say it's a 90 degree elbow.
If it is a 90 degree fitting, my only comment is that that does go against the manufacturer's recommendations.

I know it's tricky. I broke the recommendations too, but my transgression is a 90 degree fitting on the outlet side.
The manufacturer advised me that if you have to have an 90 degree angle fitting it is preferable to have it on the outlet.
They also said that a 45 degree on each side was better than using one straight and one 90.

But even so they said this was about shooting for the ideal setup and the Cube still gives good readings even in less than ideal circumstances.

Also note that the manufacturer advised me that the preference for fittings was: brass best, steel 2nd, aluminium 3rd. I've used steel.
But I guess this is not quite so much of an issue with your static installation. With mine the Cube is 'floating' on the hoses.
 
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Hey Brian,
Just responding based on what I was told via email by a different EI Tech Rep named Dave Campbell on the [email protected] email on 26th Aug 2009.
Like I said, it appears it will work any which way but preference is to avoid 90 degree on inlet if possible. Here's the email

"Steve-
Fittings first: brass is the first choice, then steel, then aluminum. In all cases we assume flex line in and out of the transducer and some sort of thread sealant/lubricant.
........
The length of flex does not need to be 5 inches- it could be less.
You can use 45 and 90 degree fittings in both the in and out ports of the transducer. We would prefer that a 90 not be used in the in port, but our tests show that it is not really a factor in the flow indication. If you have to make a 90 degree turn, maybe a 45 in and 45 out?
Please let me know if we can help.
Thank you,
Dave Campbell"
 
Yep all sorts of opinions out there even within the same manufacturer.....

Hey Brian,
Just responding based on what I was told via email by a different EI Tech Rep named Dave Campbell on the [email protected] email on 26th Aug 2009.
Like I said, it appears it will work any which way but preference is to avoid 90 degree on inlet if possible. Here's the email

"Steve-
Fittings first: brass is the first choice, then steel, then aluminum. In all cases we assume flex line in and out of the transducer and some sort of thread sealant/lubricant.
........
The length of flex does not need to be 5 inches- it could be less.
You can use 45 and 90 degree fittings in both the in and out ports of the transducer. We would prefer that a 90 not be used in the in port, but our tests show that it is not really a factor in the flow indication. If you have to make a 90 degree turn, maybe a 45 in and 45 out?
Please let me know if we can help.
Thank you,

Dave Campbell"
 
I have a flow scan with a 90 degree fitting right before it and it has been very accurate. I think older flow scans had problems but not newer ones.
 
Looks great Mike - I'm copying you so be sure to let me know how it goes :D My cube will hang under the white bracket in this picture:


Looking at your FWF, I noticed the adel clamp that holds the breather tube... is that attached in line with the left side of the firewall recess? You can see in the pic that I managed to mount my red cube aligned with the left side of the recess (attached to the vertical angle on the backside)... so now I'm not sure what to do with my oil breather tube. One thought I had was to move the clamp upwards and then bend the tube forward as it goes down (so it passes in front of the red cube).

That is the LAST thing I have to do to my firewall - have any ideas? I don't want to move my red cube.... I was thinking of clamping the tube to the engine mount if nothing else presents itself.

BTW - I've never heard the recommendation for brass fittings before.

Thanks,
 
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Floscan on firewall...

@Bubblehead,

Did you mount your floscan on the firewall? The manufacture instructions definitely say not to mount it to the engine, but I was wondering about the firewall.

I'd like to have an installation similar to Brantel's.

Michael-
 
Floscan not E.I. Redcube

I was specifically asking about the Floscan 201B, not the E.I. Red Cube. I find many mounting discussions and pictures concerning the E.I. Red Cube, but not so many with the Floscan unit.

Thanks,
Michael-
 
I was specifically asking about the Floscan 201B, not the E.I. Red Cube. I find many mounting discussions and pictures concerning the E.I. Red Cube, but not so many with the Floscan unit.

Thanks,
Michael-

Off topic, but this location is pretty common and works well. Variants depending on if your brining the fuel line in through the rear baffle or through the inter cylinder baffle. Firewall is fine. You just do not want to mount it hard to the engine or other high vibration location without a hose. This was a fit up for hose length so the install was not quite complete when this was taken but you get the idea.
3rlhl.jpg
 
Off topic, but this location is pretty common and works well. Variants depending on if your brining the fuel line in through the rear baffle or through the inter cylinder baffle. Firewall is fine. You just do not want to mount it hard to the engine or other high vibration location without a hose. This was a fit up for hose length so the install was not quite complete when this was taken but you get the idea.

Gonna make the fuel awfully hot during shutdown would be my only concern.
 
Gonna make the fuel awfully hot during shutdown would be my only concern.

That is exactly what I see wrong with that installation.

Mine is installed exactly in the first photo that started this thread.

After almost 900 hours, there is no cracking or other issues with the installation.

The reason this no problems is that both ends of the "U" are fixed to the firewall and there is no chance for movement between the two items to cause cracking. I just had the "U" off my plane to inspect it and it looks like it did the day I made it.

Also, there are not fuel heating issues or low spots in the fuel lines to collect water and trash. Before the fuel flow scanner any water or debris would fall back to the gascolator and after it, it is all downhill to the carb.

I had to look twice to see if this was my installation. (It is not.)
This has worked out well with no issues and no reason to move it.

20ksvhd.jpg
 
Gonna make the fuel awfully hot during shutdown would be my only concern.

Don’t want to throw off topic anymore, but it is a non issue. Coolest place there is in operation and never has been an issue on shut down or hot restart for me. I copied this from several high time installations on other RV’s and mine has been trouble free for 750 hours.
So, make your own choice but let’s not assume. This location was a discussion many years ago and no sense in dredging it up again unless you have hard facts to support assumption.
By the way, you have to get to the spider one way or another.
 
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Carb

I'm carburated. I think I'm going to install my Floscan on the firewall just like Brantel installed his red cube on the firewall.

Thanks,
Michael-
 
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