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DIY Fire Suppression System

With my engine out for the winter for upgrades (along with pretty much everything else), I thought it would be a good time to build my own fire suppression system.

Nothing too fancy, just a rechargeable chemical retardant that is triggered from the drivers seat that sprays the engine (mostly the carbs)

So, I went to the store and bought a nice quality metal, rechargeable fire extinguisher that had a screw on nozzle. $32

Then to the fastener shop (where I bought my air suspension fittings / lines / etc). to pick up:
  • adapters
  • a PTC (push to connect) Y
  • two PTC males
  • brass bulkhead fittings
  • misc brass adapters
  • 14' of 1/4 high pressure flexible line

all this stuff: $44
bike cable: $4
bill so far: $80

I just came back from the garage and assembled the spray nozzles. I used brass end caps and drilled in three 4mm holes at 30 degrees with a spread of ~80 wide. then I chamfered the holes to get a cone-shape spray.

Essentially, this should spray the crap out of my carbs.

I used the trusted blow-through it with your hand to feel the spray direction and it passed the test.

I am going to do a dry run once it's installed (with no engine and a tarp on the floor), so if I got the spray pattern wrong, I'll just buy new $.50 brass caps and do it again.

I am going to mount the fire extinguisher under the drivers door sill (mounted to the metal frame held on to the mount with two HD hose clamps. oh ya - the awesome bike brake cable to activate the FE - picked one of those up too.

Then I plan to put the pull '**** there is smoke coming from back there' handle below the rear hood release. I am going to use some sort of quick release cotter pin to stop accidental triggers.

I plan to trim the FE handle so it doesn't get in the way (see the black electricians tape?)

I also picked up another rechargeable fire extinguisher (big 6lb-er). I'm going to test with that.

I am going to use the fire extinguisher red "cotter pin" to prevent accidental discharge.

This is a class B/C electrical and flammable petroleum products chemical spray. messy, yes. effective, yes.

Update: got it working!

Masked off the engine bay and deck lid (i had no idea what this would do when I pulled the trigger)

in action:

i'm happy with the nozzles I made (angle / volume)

so, aside from mounting the bottle - I picked up a handle and will fab up the rest of the emergency pull. FYI - it is very easy to squeeze the bottle.

Mounted the extinguisher last night after cutting the lower handle and installing a spring. I tested my cable setup a few weeks ago and noticed a bit more resistance in the cable than I was expecting, so I added a fairly weak return spring. it's held in place by the cable.

I also picked up some stainless T-bolt clamps instead of the crappy ones shown in the picture. (i don't want this falling off)

Replaced the hose clamps with the $6 ones

Tapped the release handle with some metric thread and lock-tighted the bolt on (after I cut the head off of the 50mm bolt and drilled a small hole in the end)

Sanded and prepped for paint. painted three times with vintage ivory (yayyy I love the chemical bubbling reaction from the two kinds of paint. I was clear coating the handle and then I looked at what kind of paint it was. d'oh. start over. good thing I have 4877 projects on the go and I don't have to wait for wet paint.)

Here it is being test fit along with the sleeve. I wanted a tight fit/look. I'll see if I can grab a shot of it done. looks purdy all painted with safety pin.


Drilled the threaded bolt (sans head) and sleeve for safely pin. fancy dipped-in-a-can-of-red-paint-red (fitting colour name):

Then I fabbed up three different adjustable cable setups. This is the one I went with. simple. strong and adjustable.

FYI - I drilled out the middle of an allan head bolt and threaded a piece of metal I had laying around.

Simple cable crimp-thingy to hold it tight, and done. That's it.

Hopefully I never have to use it, but if I do, I know it works.