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What to finish before hanging engine?

pilot28906

Well Known Member
The engine I ordered during SNF should arrive any day now. I have done everything the plans calls for on the firewall before hanging the engine. Just wondering what you experienced folks would recommend completing before starting the engine install that is not in the plans?

Thanks in advance.
John
 
Would it be better to wait with cowling until the engine have hung for a while (settling) and also the front would need adjustment for the prop. ?

However, there is a lot of surface stuff, pinholes etc. that can be dealt with now.
 
I thought the engine/prop had to be installed to get the cowling fit correct? Is the cowling easier before the engine install?

Thanks for the advice.
 
If you are considering the Fiberfrax/stainless foil type of firewall insulation, now is the time to install it.
 
The airplane is light right now. Lift it and fit your gear leg fairings, wheel pants, and intersection fairings.

You could also squeegie several coats of epoxy on the inside of your cowl and maybe paint the inside. I'd wait to see where your exhaust system is positioned versus the cowl to install any cowl insulation.
 
+1 for the firewall insulation before hanging.
+1 for the wheel pants and gear leg fairings. The only thing you won't be able to finish are the top intersection fairings until you have the cowl in place. I'd leave the cowl work until you have the engine hung and prop in place (specifically the backing plate to determine the cowl alignment).
I'd wrap up everything you possibly could on the airframe (canopy, paint, interior etc) and firewall before you hang the engine, including but not limited to:
Firewall pass throughs for engine sensors (one on the left and right)
Firewall passthrough for the main bus wire (should be kept sensors)
Alternator shunt and ANL fuse block.
Main bus fuse (if you choose to install one, which I did because I have backup batteries in my avionics).
Engine controls
Start/Master relays (bolt pattern for the BlueSeas 9012 low draw relay is different from the Van's relay, should you choose to use one)
Engine sensor manifold block - drill the holes but leave this off as you will need to add the fittings.
Heater box.
I wouldn't (and didn't) do any avionics at this stage, given that they go out of date so quickly (apart from installing cutting the panel/sub panel for radio racks, installing shunts and autopilot servo). That said, it's good to have an general avionics plan at this stage so you can decide on mounting configurations. I even purchased some racks from Stein early to achieve this fitment task, but just held off purchasing the expensive bits.
More importantly, I would be thinking how you will be preserving the engine after you have removed it from it's shipping preservation (if it comes from Lycoming, it will be in a sealed plastic bag with desiccant in it, keeping it in a perfectly low humidity environment). Once it's out, the clock starts ticking. I worked pretty much full time on my aircraft and it still took me 10 months from the time I had the engine hung to the time I had the aircraft completed and cranking over. They say in the lycoming instructions that you shouldn't move the crankshaft as it will wipe the preserving oils off the cam surfaces. Fine in theory, but when you are trying to fit the prop etc., sometimes you have to rotate it. The easiest way to mitigate any subsequent corrosion risk (assuming you don't live in the middle of the desert somewhere) is to install desiccant spark plugs (one in the top of each cylinder), seal off the intake and exhaust, and make a dehydrator for circulating dry air through the crankcase. The one I made is just a 2W fish tank pump that I modified to suck air from a hose instead of from beneath itself, which in turn was drawn from the desiccant box through a modified respirator filter (to ensure no desiccant dust gets in the engine). Use the orange desiccant, as the blue stuff is a know carcinogen. The air gets pumped into the dipstick port and drawn out the crankcase breather and pushed back into the desiccant box through a fish tank air stone, but first via a jar with a humidity sensor. It generally keeps the engine at 10% humidity or less. At that level, even with no oil on the cam, you will not get corrosion. Now that I have the engine running, I'm still using when I know the engine will sit for more than a few days. It's interesting to note that about 45 minutes after shutdown, then engine can still be at over 110 deg F, and the humidity 75%. When the engine cools down, the air will normally reach its saturation point, and the moisture will be forced out of suspension and onto your metal components. Even with my miserable 2W pump, I'm able to drop the humidity at a rate of 2% per hour, until it settles on this sub 10% level. The engine has been run about half a dozen times now, and with this and 10 months of non stop work, the desiccant still hasn't come close to reaching saturation. When it does I will just need to put it in a metal tray in the oven and recharge it.
I hope this helps.
Tom.
RV-7
Awaiting final inspection.

10i9c08.jpg
 
Thanks for the information guys; gear leg and wheel fairings next! Where are most making the firewall penetrations for the engine sensors?

Thanks,
 
You might want to consider installing the prop governor before hanging the engine, if using an aft mounted governor. They are sometimes difficult to mount after the engine is mounted. Same with the engine driven fuel pump, but that is usually already mounted depending on your situation. The mags, if used, can wait if you want because they might be in the way of the engine mount while trying to get the bolts lined up. Also, the fitting for your oil pressure source can be impossible to install after the engine is on, if using the 45degree #4 fitting (steel preferred) because of engine mount interference, again, depending on your engine configuration.
 
I am almost in this same situation. I am planning on doing the firewall insulation. Is the general consensus just to do the firewall insulation then cut all the holes later through the foil and fiberfrax? My cowl is coming in about a month so would have to hang the engine to work on that, but I have done nothing to the firewall yet. Would it be stupid to hang the engine to do the cowl then remove it to do the rest of the firewall work?
 
I'm doing this from memory, so I may miss something.

1. Two Platenuts on the aft side of the firewall, along the top of the prop governor recess to hold the the oil pressure line.
2. One Platenuts on the aft side of the firewall, low on the left side of the prop governor recess to hold the oil breather tube.
3. Hole to the left and below the two contactors to bring the wires into the cockpit.
4. Two holes up high on either side, not above the battery, to bring sensor wires to your EMS.
5. Install you forest of tabs ground blocks on both sides of the firewall. Place them where you can bolt the ground strap through the forest of tabs.
6. Add Platenut to keep positive power line from moving. Place it about half way down the line.
7. Remove Platenuts from the battery box and place them on the inside of the firewall. This makes performing future maintenance easier as you will be able to remove the battery box by yourself.

Don't forget to install the restricted oil pressure fitting on your engine before you hang it. Otherwise, you will have to take the engine off, install it, and hang it again.
 
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I just hung the engine yesterday. Here is my plan:
- Fit cowl. I have an old Hartzell hub to use to bolt on the engine instead of the prop itself. Don?t fit the cowl without a hub (with back plate) or prop with the back plate.
- Figure out where to put all the firewall mounted stuff and drill holes, make brackets as needed. I mount the oil cooler on the firewall (same as the first two RV projects).
- Make the firewall wire penetrator. I?m using the SS unit Van?s now sells for the RV-14, part number FF-00001. I?ll use a piece of fire sleeve on the inside of the penetrator, and a larger piece on the outside.
- No need to hang exhaust yet. Keep the engine sealed as long as possible.
- After the cowl is fitted, I?ll remove the engine by removing the engine mount.
- Now with a bare firewall, I?ll do the engine side Fiberfax/SS cladding. As all the firewall mounted stuff have holes drilled, I?ll back drill through this sandwich. Note - the engine mounts do not have this sandwich under them.
- Prep cowl for paint. Prime interior and top coat with a rattle can white paint. Prime the exterior, wet sand, repeat as needed so it is ready for final paint.

I?ll take the plane to paint with the engine off. There is a real paintbooth at the airpark I can use and without the engine I don?t have to worry about tipping it over (I have 75# of lead shot on the tail now).

Carl
832_EE653-_EC5_B-4640-9078-482295_EDA759.jpg
 
I'm a newbie at this but it made sense to me to have the engine on to figure out the best locations for the holes and to work the cowl. I know it's not really necessary to have the engine on for the hole locations. Then remove the engine to drill holes and insulate. I was wondering if taking the mount off with the engine attached was the way to go. Makes sense!
 
There are a half dozen of so rivets for the bottom skin to the firewall flange in the middle, where the cowling goes under the exhaust. One of the holes is used for a bolt holding the exit air support bracket. The other holes are pretty hard to rivet once your engine mount is installed. Get them now while you can do it easily. I didn't and had to use pop rivets. The rest of the rivets on the firewall flange need to wait until you do your cowling attach, but these few can be done sooner.
 
Engine installation (on/off)

Once the engine is bolted up to the motor mount and you don't have to deal with the lord mounts anymore, it's easy to temporarily bolt the entire assembly up to the firewall with four bolts. An engine hoist or crane makes easy work of that and you can take everything on and off as needed.

Mark
 
Once the engine is bolted up to the motor mount and you don't have to deal with the lord mounts anymore, it's easy to temporarily bolt the entire assembly up to the firewall with four bolts. An engine hoist or crane makes easy work of that and you can take everything on and off as needed.

Mark

That depends on if it is a taildragger or not.
 
Mine is. All I do is level the fuselage out and everything goes together easily. Does that front landing gear come off on a nose Dragger?

Having had the engine off a couple of times while building and rebuilding, my preference is to remove the engine from the mount. Then, with luck and planning, it never comes off again.

The nose gear is held on with one bolt, same as the mains on the side-by-side's. (I've not seen a -14, so I'm not sure how they bolt up.)
 
Having had the engine off a couple of times while building and rebuilding, my preference is to remove the engine from the mount. Then, with luck and planning, it never comes off again.

The nose gear is held on with one bolt, same as the mains on the side-by-side's. (I've not seen a -14, so I'm not sure how they bolt up.)

Hey Bill,

The -7 that I'm building has the same fuselage as your -9. Those lord mounts can be a real pain in the rear...I wish I knew your trick for dealing with them. LOL!! Once I had mine on I didn't want to take them off. I'm not familiar with the way the 14's bolt up either, but it may indeed be easier to deal with the lord mounts rather than the main engine/ firewall mount. However, I agree, whichever way a person decides to do it, the least number of times that you have to fool around with it the better off you are.

Mark
 
Not necessarily the firewall hangings before the engine... It's real easy to put things on now, but once the engine is on, those screws and bolts can get ugly to access. Use nutplates on the firewall instead of bolts with nuts, so you can remove the bolts from just one side, no helper required.

Double check your oil filter installation, so you can take the filter off without making a mess of everything. I've not had a remote oil filter, but sure sounds like a good idea.

Find as many planes as you can to look at, and check them all for maintainability. You can either do the work know with your brain, or later on with skinned knuckles and cuss words...
 
Hey Bill,

The -7 that I'm building has the same fuselage as your -9. Those lord mounts can be a real pain in the rear...I wish I knew your trick for dealing with them. LOL!! Once I had mine on I didn't want to take them off. I'm not familiar with the way the 14's bolt up either, but it may indeed be easier to deal with the lord mounts rather than the main engine/ firewall mount. However, I agree, whichever way a person decides to do it, the least number of times that you have to fool around with it the better off you are.

Mark

Here is my trick.

I've hung four engines following the steps outlined in that guide. The first time I did it by myself and it went very fast. About 1/2 a beer to complete.

Everytime since I have had helpers and it takes longer.

You are right, it is still a pain. The list I posted earlier in this thread should help alleviate some pain.
 
Cowl

The cowling is much easer to put on without the engine, or prop.
I have some pictures of how to do it in the fiberglass section of these forums
You need an old engine block and crank. I got mine from Americas Aircraft engines, and another one from a dealer of used engine parts. It cost less than $100
 
Thanks for the info.

Do the gear leg fairings have to be realigned each time they are removed?

I see several builder sites that seem to wait until after they are flying to install the gear leg fairings and wheel pants. Is it good to have the fairings and wheel paints on while early flying in phase 1?
 
Here is my trick.

I've hung four engines following the steps outlined in that guide. The first time I did it by myself and it went very fast. About 1/2 a beer to complete.

Everytime since I have had helpers and it takes longer.

You are right, it is still a pain. The list I posted earlier in this thread should help alleviate some pain.

Here's an alternate method (bottom first method)

http://myrv8.com/2015/08/hanging-the-engine/

I did this in 45 mins, solo. A total non event. Take a look and see if this works for you. I agree; I'm not sure that a helper helps (and, then you have less beer)
 
Fuel pump cooling shroud

Much easier to install whilst you have access to the back of the engine!
 
More importantly, I would be thinking how you will be preserving the engine after you have removed it from it's shipping preservation (if it comes from Lycoming, it will be in a sealed plastic bag with desiccant in it, keeping it in a perfectly low humidity environment). Once it's out, the clock starts ticking. I worked pretty much full time on my aircraft and it still took me 10 months from the time I had the engine hung to the time I had the aircraft completed and cranking over. They say in the lycoming instructions that you shouldn't move the crankshaft as it will wipe the preserving oils off the cam surfaces. Fine in theory, but when you are trying to fit the prop etc., sometimes you have to rotate it. The easiest way to mitigate any subsequent corrosion risk (assuming you don't live in the middle of the desert somewhere) is to install desiccant spark plugs (one in the top of each cylinder), seal off the intake and exhaust, and make a dehydrator for circulating dry air through the crankcase. The one I made is just a 2W fish tank pump that I modified to suck air from a hose instead of from beneath itself, which in turn was drawn from the desiccant box through a modified respirator filter (to ensure no desiccant dust gets in the engine). Use the orange desiccant, as the blue stuff is a know carcinogen. The air gets pumped into the dipstick port and drawn out the crankcase breather and pushed back into the desiccant box through a fish tank air stone, but first via a jar with a humidity sensor. It generally keeps the engine at 10% humidity or less. At that level, even with no oil on the cam, you will not get corrosion. Now that I have the engine running, I'm still using when I know the engine will sit for more than a few days. It's interesting to note that about 45 minutes after shutdown, then engine can still be at over 110 deg F, and the humidity 75%. When the engine cools down, the air will normally reach its saturation point, and the moisture will be forced out of suspension and onto your metal components. Even with my miserable 2W pump, I'm able to drop the humidity at a rate of 2% per hour, until it settles on this sub 10% level. The engine has been run about half a dozen times now, and with this and 10 months of non stop work, the desiccant still hasn't come close to reaching saturation. When it does I will just need to put it in a metal tray in the oven and recharge it.

10i9c08.jpg

Ok, I really like this little dehumidifier and will be building one for my plane when its in the hanger waiting for its next adventure.

The question I have though is, as it pertains to initial hanging and fitting things as a newbie first timer, couldn't you hang it and figure out what goes where, handle the cowling and whatnot and pull it back off and re-bag it with some new desiccant packs sealed in until you're ready for the final hanging and first starts?

caveat -- I have not even seen a new engine and am a ways away from even hoping to see one.
 
You could put it back in the box, but the plastic bag is heat sealed at the factory, so you would struggle to get this properly sealed again. Also, once you've got the engine on, it's not that much longer before you've begun doing things like installing the exhaust system etc. and once you've got things bolted on, it doesn't make much sense to pull it off again.
I've put together a more detailed post covering the assembly of this device in the following thread.
http://www.vansairforce.com/community/showthread.php?t=157922
Tom.
 
Thanks for the info.

Do the gear leg fairings have to be realigned each time they are removed?

I see several builder sites that seem to wait until after they are flying to install the gear leg fairings and wheel pants. Is it good to have the fairings and wheel paints on while early flying in phase 1?

No, once you do the initial alignment, the intersection fairings will keep the gear leg fairings in proper orientation. I went with the optional wooden gear leg shimmy dampers, and when these are floxed/fiberglassed in place, the alignment is locked in even more. If it makes you feel better, you can put an index mark up by the hose clamp on both the gear leg and gear leg fairing.

I chose to install the gear leg fairings, but not the wheel pants, for Phase 1. You're gonna want to check on the brakes, brake fittings, etc. after every flight in the early going anyway. Plus, it's a rush after you've flown it a while to see the speed you pick up after fitting the wheel pants! :)
 
Timely thread, thanks! I just flipped the fuselage over and the structural parts are moving quickly; I'm rapidly approaching the point where I'll need to start doing systems installations.

The big issue is trying to figure out where to do my firewall penetrations and battery mounts without having the engine mounted at least temporarily. Going dual electrical systems and EFI makes the fuel line routing a little trickier.
 
Here's an alternate method (bottom first method)

http://myrv8.com/2015/08/hanging-the-engine/

I did this in 45 mins, solo. A total non event. Take a look and see if this works for you. I agree; I'm not sure that a helper helps (and, then you have less beer)

I used your method when hanging my engine a few weeks ago. By myself, it took maybe an hour, but some of that was chatting with a fellow pilot who saw me working on an airplane in the church parking lot and wanted to see what was going on!
 
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