I had to fish an EFI harness through a hole in the firewall and in order to get all the connectors through, I had to make a 2" hole. Now that all the connectors are on the engine side, the remaining wiring trunk going through the hole is maybe 1" diameter. So now I have a 1" bundle going through a 2" hole. I've searched McMaster and google but can't find a grommet with a large diameter but small opening. Any ideas on maybe how to make something that will work?
That's where a Guy should have had a $5.oo tool to remove the wire pins from the plug and poked them through the 1" hole then put them back in the large plug reciever. There are some large gromets with small holes but you'll still have the same issue unless you split it. Sounds like you need to make a Boot. The Wizzard
Any tool supplier will have them. Matco, Snap-Off, Sears, There is a couple different ones to cover all plug in terminals. This one I happened to get off the wall at a Harley Shop. It was 1 I didn't have and hadn't seen before. Ends up being the 1 I use the most. The Wizzard
Ace hardware. Remember ace is the place with the helpfull hardware man. Ace had gromets that are blank, then you cut the hole in it to size for your wire bundle. I have also use a piece of fuel line split lenghtwise on a large hole.
Go to an upholstery shop and get a small length of rubber coated metal pinch weld molding and put it in. I've done it many times and holds great! They even usually have a couple of sizes, I like the 1/4". McMaster-carr carries it "Self-Gripping Vinyl Edge Trim with Metal Core"
I picked up a grommet from a late model Mustang in a junk yard that was oval shaped but had a 1" hole for the wires. I was able to stretch the hole enough to get my wiring/plug through it and the outer diameter fit a large enough hole to get the plug through the firewall.
Make one like the Summit one pictured. Round flange, piece of rubber in it, bolt it down. Wont cost $15 like summits.
You can also try door loom or firewall grommets. They are for larger holes initially but have smaller ends
I Last one I dis I split the grommet and put it over the wiring. If you can't get the grommet to close tight enough on the wires maybe try some of the black strip caulk
Visit the junk yards. Late 80's to 92 chevy truck / suburban with tbi engine/ computer harness have the grommet that you need.
I went to tractor supply company, got a hunk of rubber made it fit and put a slit in it like a C so it goes over everything. Also have a couple areas with vacuum tube split lengthwise and over the edge to protect from rubbing.
Frozen solid rubber lathes beautifully. I've lathed gromments that weren't available using rear axle snubber in my metal lathe.
Many 60's Fords had accelerator pedal boots and grommets that would look kind of slick. Autokrafters should have them.
Floor pan drain plug from just about any semi-modern car you can imagine, then punch your own hole in the rubber.
The Jalopy Journal
