Topic: Non conductive silicone – Antique Outboard Motor Club,Inc

This topic has 13 replies, 11 voices, and was last updated 8 years, 6 months ago by cajuncook1.

Viewing 10 posts - 1 through 10 (of 14 total)

1 2 →

Author

Posts
October 3, 2015 at 6:29 pm #2694
Dave Hostetter
Participant
US Member - 2 Years
I need to add insulation in the mag plate cavity under the coil on a Johnson A35. In 1927, the cavity was filled with a hard tar like material that was removed to put in new spark plug wires. Without new insulation, the coil arcs to the mag plate. Can anyone suggest a non conductive silicone or similar caulk? Thanks

Dave H
October 3, 2015 at 7:39 pm #25062
dmbono
Participant
I tucked a piece of rubber roofing sheet under mine.
October 3, 2015 at 8:47 pm #25066
crosbyman
Participant
Canada Member - 2 Years
the best would probably be high voltage silicone used to insulate the B+ high voltage coil in TV,s

electronic shops (Radio Shack ?) sell it for insulating the HV coils when the HV coils start to arc or screeech with a a high pitch wistle .

Joining AOMCI has priviledges 🙂
October 3, 2015 at 9:21 pm #25067
kerry
Participant
US Member - 1 Year (includes $3 online payment fee)
Would dielectric grease, like used in light sockets, work? Just asking the experts just in case I run into the same situation.

If you have too many, AND not enough, you're a collector.
October 3, 2015 at 10:06 pm #25069
vintin
Participant
Anyone here ever used Ambroid cement on arcing coils, etc?
October 4, 2015 at 1:09 am #25089
joecb
Participant
US Member - 2 Years
Be very careful about the indiscriminate use of "rubber material" as high voltage insulation. Many compounds of black colored rubber use carbon black as a filler, these compounds will conduct electricity. I found this out after trying to use a piece of black rubber automotive hose as a grommet on a spark plug lead. You can test for some level of conductivity with a normal VOM set on the highest resistance scale.
Joe B
October 4, 2015 at 2:16 am #25092
lotec
Participant
Get all the bits of the tar you took out, heat them up in a metal can and re-pour it back in. If you are careful you can re-use about 80% of it – that stuff lasted 80-90 years, do you really think anything new will do as well? And there is no truth to the reports there are PCBs in there, however, I wouldn’t inhale the fumes.
October 8, 2015 at 12:49 pm #25291
The Boat House
Participant
- This reply was modified 5 years, 5 months ago by The Boat House.
- This reply was modified 3 years, 1 month ago by The Boat House.
October 8, 2015 at 1:51 pm #25295
cajuncook1
Participant
Please take into consideration, that what ever you use as insulation, must have a certain heat tolerance. The heat of the power head and also the temperature of environment. The combination of the temperature of the power head, heat generated by the ignition, and the temperature of the metal in the summer may cause some insulator material to melt and get real messy. So, investigate the heat tolerances of the what ever you plan to use.
October 8, 2015 at 1:56 pm #25297
crosbyman
Participant
Canada Member - 2 Years
there is a special silicone for sealing stove pipes used with pellet stoves.

Since the exhaust of pellet stove is "pressurized" by an exhaust fan you neeed to seal joints with this silicone.

it is heat tolerant and likely a good insulator being clear silicone

Joining AOMCI has priviledges 🙂
Author

Posts