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Battery Box Installation on Firewall 3 out of 6?

jackking123

Well Known Member
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Installing this optional kit I found they only use 3 nutplate/bolts to attach to firewall, yet the angles are drilled (for bolt and nut plate for 6).
Have it drilled up for three, but I think I will go a head and drill the other 3 for total of 6. I see no downside except weight and expense.
Suppose I could "blank" those nut plate and bolt holes in the angle with rivets.
Comments, suggestions?

Rubbing, Fretting, battery box to firewall and box to battery. I am thinking some teflon tape to keep two metal parts not attached from buzzing and vibrating? Heat is an issue.
Comments, suggestions?
 
I think the other holes are for other models or location configurations. Three seems to work fine.
The mod that really helps, is to cut the front off the box and use two hinges. Add an eighth to quarter inch of depth so you have more options later. Use a piece of baffle material to fill the excess space.
First time, I pulled the battery, it wouldn't come out. Silly me didn't think about the stuff above.

Another tip installing the box. Buy three long 10-32 hardware store bolts and two butterfly nuts. Cut the heads off. Screw the studs into the nutplates enough so they won't fall out. Push the box into place. Climb inside and spin on two nuts. Remove the third stud and install the AN3 bolt. Remove another stud and repeat. The studs keep the box aligned so the bolts will go in.
 
I think the other holes are for other models or location configurations. Three seems to work fine.
The mod that really helps, is to cut the front off the box and use two hinges. Add an eighth to quarter inch of depth so you have more options later. Use a piece of baffle material to fill the excess space.
First time, I pulled the battery, it wouldn't come out. Silly me didn't think about the stuff above.

Another tip installing the box. Buy three long 10-32 hardware store bolts and two butterfly nuts. Cut the heads off. Screw the studs into the nutplates enough so they won't fall out. Push the box into place. Climb inside and spin on two nuts. Remove the third stud and install the AN3 bolt. Remove another stud and repeat. The studs keep the box aligned so the bolts will go in.

That is great idea... But not sure I understand. Why would the box need to come off firewall at least frequently?

Can you not slide battery up?
You are saying there is not enough room to slide it up?
Keeping firewall real estate free is not an issue, but engine accessories, P-Mag, Prop Gov in the way? Not sure.

I suppose I could go with Earth-X and fill in the space as you say.... getting that smaller (lighter) battery out should be easy (easier)?
 
That is great idea... But not sure I understand. Why would the box need to come off firewall at least frequently?

Can you not slide battery up?
You are saying there is not enough room to slide it up?
Keeping firewall real estate free is not an issue, but engine accessories, P-Mag, Prop Gov in the way? Not sure.

I suppose I could go with Earth-X and fill in the space as you say.... getting that smaller (lighter) battery out should be easy (easier)?
The battery box shouldn't need to come off. Mine did! My fault. My Manifold Pressure Transducer is mounted on the firewall and in the way of sliding the battery up far enough to remove it. The studs were my solution to installing it without help.
Pulling two hinge pins makes the battery swap an easy job. I can swap a battery in minutes and the cuss jar doesn't make a profit. It comes right out. Far more options other than just going up.
I'm not saying use the EarthX battery. Their box is really nice. I am suggesting modifying whatever box so almost any 680 size battery will fit. They are not all identical in size. What if you have a battery failure and the only 680 you find won't slide in?
I have a $50 Mighty Max 680 clone off Amazon. It's just a tad thicker than an Odessey 680.
 
The battery box shouldn't need to come off. Mine did! My fault. My Manifold Pressure Transducer is mounted on the firewall and in the way of sliding the battery up far enough to remove it. The studs were my solution to installing it without help.
Pulling two hinge pins makes the battery swap an easy job. I can swap a battery in minutes and the cuss jar doesn't make a profit. It comes right out. Far more options other than just going up.
I'm not saying use the EarthX battery. Their box is really nice. I am suggesting modifying whatever box so almost any 680 size battery will fit. They are not all identical in size. What if you have a battery failure and the only 680 you find won't slide in?
I have a $50 Mighty Max 680 clone off Amazon. It's just a tad thicker than an Odessey 680.

Roger that Larry, good advice as usual my friend... May be I will go with 3 bolts not 6... since it's good enough. Less to unbolt if the battery box needs to come off. The hinge idea is also a good idea as well. Cheers...
 
I put the nutplates on the angles behind the firewall and put the bolts through from the engine side. Makes any later mods or repairs easier.

Ed

Another good tip... I just got done with lighting holes in box and the cross bar... that was a lot of work. Ha ha.
 
Cobalt drills. Start small. Step drills work pretty well for enlarging holes.

Ed

Oh yes, cobalt is great. I'll keep those in mind. Need to get some. I get along fine with SS I just hate it... ha ha. I go slow (drill speed), use Boeing lube. I have a bunch of jobber drills. if I wear them out no big deal. I save my good drills for the aluminum. Almost done with firewall for now...

Bat box lighting holes turned out to be more time than expected. For one I used my trusty fly cutters on drill press. Backed up with wood, drill press, going slow got through it.... The drill press belt will slip if cutter catches without drama, a safety feature. Again Boeing Lube. You have to go slow, and I had to stop to sharpen the cutter. I was using the small one, got out my bigger fly cutter out and it worked better... but 2" Dia is almost min size it can do.

What was a shock was the BURR cutting battery box lighting holes... Oh my gosh I spend hours cutting and cleaning those burrs up. Ha ha. The burrs were tough to clean up... but it came out OK. A hole punch or good metal hole saw better? Likely. Hey I like fly cutters, cheap, flexible, but a little hazardous if not careful, and the burr may be worse.

Anyway20250316_235043.jpg20250316_235523.jpg STEEL, be it mild steel or stainless is a pain...
 
I've got a bunch of hole saws that I use for that kind of thing. If you cut halfway through and turn it over, there's little or no burr.

Ed
 
I've got a bunch of hole saws that I use for that kind of thing. If you cut halfway through and turn it over, there's little or no burr.

Ed
NOW YOU TELL ME!!!!!! Ha ha. Another tip... The problem with battery BOX is one side access and the holes are slightly off set (due to well the dwg and the seam on back side). But noted. Thks.
 
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