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Firewall Forward

wirejock

Well Known Member
Does anyone have a really good online builder log detailing the IO-360-M1B and associated Firewall Forward stuff?
Vans plans are ok but they don't show the engine and all the parts to install.
I'm looking for photos and detailed steps from crate to mounting the engine.
I hate bothering my friend Jereme with endless questions when a few photos would probably suffice.
I promise to document this stage just like the rest of my build for other lost souls.
Pretty sad considering how many auto engines I've built or fixed.
 
Larry

If you have any luck finding this information please let me know as well. I just finished the inventory of my firewall forward kit and I will be heading into the garage to resume building. I'm building the 7A with an IO-360 (horizontal cold air induction.)

Thank you
Ken
 
Don’t worry at all Larry. I never get tired of questions. Just remember, I’m a teacher for a living. :)

P.S. I’ve done it 3 times now so I pretty much have it memorized. Lol

I also posted a fair amount of pics and gotchas on my build log here. Start about at this page.
 
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I'm mostly through the firewall forward stuff, except for the biggies (cowl, spinner, prop, airbox/snorkel), and the great thing about FF is you can kind of do things in whatever order you want, with a few exceptions. You're right, though, it's at this point most of the great "reference" build logs online get kind of vague and incomplete. Probably people are excited to be almost done and spend more time building than writing!

Vans FF documentation comes with what looks like a complete checklist, which is what I've been following. Here's what I did so far according to my build log, please don't rely on it--use Van's documentation obviously.

Prior to mounting the engine mount

I made sure the firewall was entirely done before attaching the engine mount, including the holes for attaching the breather tube and oil pressure line, the battery + box + cables, the firewall-mounted solenoids, the firewall mounted sensor manifold (final-install the fittings before you bolt the manifold to the fw!), the cabin heat vent mechanism, and all the wire passthroughs. Like some others here, I went with the fiberfrax insulation under a thin sheet of titanium foil. That was done long ago.

Then attached the engine mount.

Prior to mounting the engine

Once you have the engine, there are some things you need to do before mounting it: I had to re-clock the prop governor control arm in order for the push-pull cable orientation to make sense. I also pre-attached the cable bracket and rod end to the governor because it would be hopeless to try to do this once the engine was mounted. I needed to install the 45 degree restrictor fitting to the oil pressure port, as they say this can't be installed with the engine mounted. I needed to remove the right magneto to do this, some have managed to do it with the magneto in place. I attached the fittings onto the fuel pump inlet and outlets, capped the fuel return port (I don't need it). They also have you install the fittings that go to and from the oil cooler at this time. I found that Lycoming already included a fitting for the connection TO the cooler, and had to add a fitting for the FROM connection. I wish I would have also final installed the oil cooler hoses at this time because they are a pain in the neck after the engine is mounted!

Then mounted the engine. Get a helper, preferably someone who did this before (thanks, wjb). And an engine hoist. And beer. It really wasn't hard at all.

After mounting the engine

From here, I did the following:

  • Attached all the sensor hoses: fuel pressure, oil pressure, manifold pressure
  • Attached the fuel lines from the firewall to the pump and from the pump to the servo
  • Made and installed crank case breather line
  • Installed the fuel overflow fitting and tube
  • Installed oil temp probe
  • Installed but did not final-tension the alternator
  • Sealed up all the inter-cylinder baffles with Permatex ultra black. Do this before the exhaust is on
  • Secured all my wire runs in the engine compartment
  • Installed tach sensor to my right mag
  • Made all the various doublers and angles for the baffles and filed the baffles to fit better around the cylinders. The baffle work is a little premature at this point--I'm going to want to fit the cowl before trimming them. I'll also need to have the baffles trimmed before cutting the hole for the oil cooler, so will have to wait for that too. If your oil cooler is baffle mounted, consider reinforcing it with an angle because according to VAF they all crack. Do some forum searches, you'll find the threads. Consider making the air dams removable. Same--forum search.
  • Installed mixture and throttle cables
  • Made the mixture and throttle linkages and installed the fuel servo/throttle body
  • Hung exhaust
  • Installed heat muff and ran fresh air tube from muff to firewall
  • Made sniffer valve drain tube and installed sniffle valve
  • Installed CHT and EGT probes
  • Installed ignition wires (all wiring besides ground strap done at this point)

And that's where I'm standing right now. Still have a lot to go:

  • Red cube flow transducer (see below)
  • Cowl
  • Spinner and prop
  • Ground strap
  • Air intake snorkel + alternate air door
  • Plumb fresh air to heat muff
  • Finish baffling
  • Mount oil cooler
  • Oil door and fill tube
  • ...and probably more that I'm overlooking in this list.

I've got some un-annotated pictures here. Not sure how helpful they'll be. I'm not much of an educator and don't feel I have the ability to write a good build log like the Usual Suspects out there on the web. This is also my first time through so the veterans here probably know all these steps colder than I do. The thing I have the most anxiety about is getting all the torques right--it seems like every fastener and fitting has a different torque call-out, and they're not all listed in the same document.

One thing you'll find: Every time you remove something from the engine, a whole bunch of preservative oil-goop will pour out. Have lots of rags around. I'll need to fully drain this at some point before putting the actual engine oil in. Still need to learn how I'm supposed to do that.

Last but not least: I've been doing this throughout the RV build, but it's doubly critical when working FF: Any step you skip, write it down so you remember to do it later. I have an entire "deferred steps" list in my build log where I keep these. For example, anything I leave hand-tight goes in the deferred steps list.

Looking forward to finally starting the engine one day! Might not be long... Hope this helped.



NOTE: For the red cube, I've decided to mount it up by the fuel divider, like some other folks here. Tom at TS Flightlines is patiently helping me get a solution in place that I'm happy with but I'm still measuring and getting exactly the right fittings and hardware I need for this. This device is one of the great under-documented parts of the build that everyone on VAF does differently, so your mileage will vary from everyone else.
 
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Ryan and Jereme

I just viewed the info you both just posted and it is extremely helpful. Nice documentation of the process.

Ken
 
Hi Larry ... I'm happy to help, too .. I successfully passed this kidney stone and the bird make very nice airplane noises now. I've been enjoying sharing ways to to avoid some of my scars with Draker and other builders. No amazing builder blogs here (the basics are on Kitlog: http://www.mykitlog.com/users/index.php?user=wjbencze&project=2206) but I did take lots of pictures .. see your PM)

Feel free to ask any questions you like ... I've found it very useful to pick the brains of someone who's done the ops recently.
 
Larry,
I don't know if my Kitlog's engine and FWL FWD sections count as "good", but give 'em a look. Hopefully they're helpful.

http://www.mykitlog.com/ScrollF4/

Note: I originally built KELLI GIRL with a Sensi FP prop. The Hartzells came later.
 
RV-14 plans

The Van's RV-14 plans really helped me even on my RV-8, so I imagine they would even be more helpful to an RV-7 builder. Also, the 360 picture of the engine after installation was useful.
 
Larry,

Have you decided if your battery box will go on pilot or passenger?

Does anybody else have experience or knowledge which might be best?

I have older prints showing 7A on pilot side with an older style battery box/ shelf. The firewall forward kit which I just received has the PC680 battery box similar to a 7 installation. I have seen A models with batteries on either side which makes me wonder which is best if I have a choice. Any builders with experience please share your thoughts.

Thanks
Ken
 
Battery box

Larry,

Have you decided if your battery box will go on pilot or passenger?

Does anybody else have experience or knowledge which might be best?

I have older prints showing 7A on pilot side with an older style battery box/ shelf. The firewall forward kit which I just received has the PC680 battery box similar to a 7 installation. I have seen A models with batteries on either side which makes me wonder which is best if I have a choice. Any builders with experience please share your thoughts.

Thanks
Ken

I haven't got that far but I usually stay with plan. However, I am installing the bigger oil cooler somewhere on the firewall. Plan was to feed it off the #3 baffle, the battery may have to be relocated.
 
I haven't got that far but I usually stay with plan. However, I am installing the bigger oil cooler somewhere on the firewall. Plan was to feed it off the #3 baffle, the battery may have to be relocated.

If you keep the battery in the standard spot (right side) there is plenty of room to put the oil cooler on the left side of firewall and take air off of the #4 baffle. Cylinder 3 has hard enough of a time cooling. Also look up DanH baffle mod for cooling that cylinder.
 
Oil cooler

If you keep the battery in the standard spot (right side) there is plenty of room to put the oil cooler on the left side of firewall and take air off of the #4 baffle. Cylinder 3 has hard enough of a time cooling. Also look up DanH baffle mod for cooling that cylinder.

Thanks everyone and especially Jereme. Please keep the comments flowing. I plan to document as much as possible to my blog Engine Page.
 
Pass through locations

More questions
I searched and looked at every photo I could find.
I even called Vans. They basically said put stuff anywhere you want but watch for stiffeners and engine mount.
I have two pass through kits (1-1/8" hole plus flange) and want to put them in the upper port and starboard corners. (Photo link below. Yellow tape.) Is there anything in those corners to steer clear? Skybolts?

Second question
I was planning a B&C 24x24 Forest of Tabs.
24 inside X 24 FWF. That looks like it will fit somewhere around the battery Starboard side to keep the ground as short as possible. Thoughts?

Third question
I'm reserving the top middle area for GPS pucks. Any issues?

https://vansairforce.net/community/attachment.php?attachmentid=8776&stc=1&d=1614292535
 
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Larry,

Have you decided if your battery box will go on pilot or passenger?

Does anybody else have experience or knowledge which might be best?

I have older prints showing 7A on pilot side with an older style battery box/ shelf. The firewall forward kit which I just received has the PC680 battery box similar to a 7 installation. I have seen A models with batteries on either side which makes me wonder which is best if I have a choice. Any builders with experience please share your thoughts.

Thanks
Ken

I didn't build the plane, somewhere along the line either the builder or previous owner put the (dual) battery box here.
.
 

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Firewall Layout

Larry,

Here is how I laid out the components on my firewall. Let me know if you have any questions on what I did.
 

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Layout

Thanks Greg.
Looks like I got pretty close to your layout.
Still have the FOT to drill and maybe a couple other little things.
Almost there.
20210226_144520.jpg
 
Ground Block

Larry,

Here is where I put my ground block. It gave good access to the battery.
 

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Another thread

Another thread said the battery has to go straight up and is really tight in the battery box. I am not there yet but the thread said the battery has to all the way up till clear of box. Something to think about.
 
I didn't build the plane, somewhere along the line either the builder or previous owner put the (dual) battery box here.
.

Your exhaust support should be connected to the motor, not the motor mount. It needs to move with the motor.
 
Really thinking about this

Is the new thing now to mount the oil cooler to the firewall? Advantages? No baffle cracking?
I am really thinking about moving my cooler to the firewall. I am following closely all these discussions. Please let us know what you all think.
 
Oil cooler

I am really thinking about moving my cooler to the firewall. I am following closely all these discussions. Please let us know what you all think.

Couple reasons why I did it.
1. Baffle issues
2. I wanted a larger oil cooler, more efficient oil cooling.
The parts posted look like they will fit and control air flow well. I also installed nutplates so the oil cooler mount can be removed for access to the back side of the engine. It's a lot of screws but if I need to get an arm in there, it's well worth it.
I'm not flying so it's worth a whopping $.02.
 
Is the new thing now to mount the oil cooler to the firewall? Advantages? No baffle cracking?

Not sure it is a new thing. I mounted my oil cooler on the engine mount after my baffles cracked and then the cooler mounting flange cracked within the first 50 hrs. No problems now after another 400 hrs. Antisplat sells a nice transition duct so you don't even have to make your own now. Working on a 4 at the moment and doing the same thing to avoid the baffle issues before they start.
 
MP sensor

Not Larry, but after a "zoom and enhance" it looks like a manifold pressure sensor.

Yes. Dynon Manifold Pressure Sensor. I finally have all the Fiberfrax and Titanium foil installed so all that stuff can get permenantly mounted now.
 
Not sure it is a new thing. I mounted my oil cooler on the engine mount after my baffles cracked and then the cooler mounting flange cracked within the first 50 hrs. No problems now after another 400 hrs. Antisplat sells a nice transition duct so you don't even have to make your own now. Working on a 4 at the moment and doing the same thing to avoid the baffle issues before they start.

Just to chime in, I mounted my oil cooler to the baffle per Vans plan, including a big beefy angle to reinforce where cracks tend to develop:



We’ll see if I become the next crack victim. Who knows?

The most confusing part was getting the vertical position of the oil cooler. Vans does not call out a measurement, but says to make it as high as possible for better cooling. Unfortunately you don’t know how high you can reasonably get it without first trimming the baffles, and you can’t do that until the cowl is fit. Do the order in which you have y to o so the stuff is weird.
 
Does anyone have a really good online builder log detailing the IO-360-M1B and associated Firewall Forward stuff?
Vans plans are ok but they don't show the engine and all the parts to install.
I'm looking for photos and detailed steps from crate to mounting the engine.
.

Hi Larry Can I piggy back on your thread and suggest another thread in a similar vein ?

I'd be interested in gotchas where builders used a non standard engine / firewall forward set up.
In my case I swapped from carb to vertical injection and as I didn't want to exchange cowlings.
Vans say most of the dimensions are same and so I'm hoping cables etc will fit. But adapting things around the throttle body etc. seems to be a bit of a challenge.

Maybe if there's enough interest and also expertise out there ?
 
More questions

Second question
I was planning a B&C 24x24 Forest of Tabs.
24 inside X 24 FWF. That looks like it will fit somewhere around the battery Starboard side to keep the ground as short as possible. Thoughts?

Ooh, another thing, Larry, I don't know what kind of avionics you are planning, but consider a 48-tabber on the cabin side if you have a lot of electronic goodies. My fairly complete All-G3X system used every single tab--not an exaggeration. When I ran the 48th circuit, I broke out in a cold sweat hoping I didn't forget anything.

Since I have few electronics on the firewall side, I did not put a tab forest on that side. Simply didn't feel I could justify it. Still have the block sitting on my shelf unused.

Also, pay attention to where you mount the forest. I just picked a convenient spot on the right side, right above my battery box. Of course, this means I can't slide the battery up and out of the box anymore. I need to take the whole battery box off the firewall to remove the battery. Don't do what I did.
 
FOT

Ooh, another thing, Larry, I don't know what kind of avionics you are planning, but consider a 48-tabber on the cabin side if you have a lot of electronic goodies. My fairly complete All-G3X system used every single tab--not an exaggeration. When I ran the 48th circuit, I broke out in a cold sweat hoping I didn't forget anything.

Since I have few electronics on the firewall side, I did not put a tab forest on that side. Simply didn't feel I could justify it. Still have the block sitting on my shelf unused.

Also, pay attention to where you mount the forest. I just picked a convenient spot on the right side, right above my battery box. Of course, this means I can't slide the battery up and out of the box anymore. I need to take the whole battery box off the firewall to remove the battery. Don't do what I did.

Hopefully 24 is enough. Pretty basic glass. However, I'm using the Advanced Control Panel. It has power and ground and handles the power, audio and data circuits. FOT is installed roughly center above the recess. Area above the battery is pretty clear. Hopefully the battery will go in and out!
 
You can double up grounds on similar low amp circuits. My harness from stein had many avionics grounds going to singular fast on connectors.
 
My location seems to work as far as battery removal. I was just working on adding the ground wire yesterday. I'm still not sure if I'll leave any of the forward side tabs but for now here is a picture of a test fit of what I have.
 

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I did the 24/24 fwd and aft of the firewall. Lots of tabs available inside but I also doubled up on several. Nothing connected to the fwd tabs but they are there if needed for future.

Off topic: My engine has a horizontal induction but I opted to install a 90° elbow for the AFP fuel injection. Was fairly easy to get all cables hooked up and keep clear of the Vetterman trombone exhaust. I have a video of the installation on Google Drive, if anyone wants to see it.
 
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