• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

ignition coil oil ?

Share this page

eschneider

eschneider

Jedi Warrior
Offline
The car I'm working on has a TR3 engine and an original ignition coil (50 years old!)

There's a screw in the top of the coil - I've heard this is to bleed/add oil? What kind of "coil oil" does one use?

No wise cracks about coil oil being next to the blinker fluid on the parts shelf......
 
No. The screw is a connection, not a place to add oil. And likely the proper oil was outlawed long ago.
 
Could never find that blinker fluid in my parts store. It must be popular,they are always out of stock.
 
It's right around the corner from the Lucas Electricharging Smoke.
I would never take cracks at coil oil or blinker fluid.
 
Hey es,

FWIW, I unscrewed the screw at the top to replace the high voltage connector on an old Lucas Sports coil I have. There was a hole into the coil with oil in it. Having nothing to loose, I added a little 3-1 Oil for good measure, leaving some room for expansion.
I got a book off eBay a few years ago called "Tuning Lucas Ignition Systems." It says "the coil is filled with insulating oil, which helps in the dissipation of heat." I'm not sure where the oil dissipates the heat to, but that's what it says. Mounted on the block, the poor coil needs all the help it can get.

Jeff
74 TR6
 
eschneider said:
The car I'm working on has a TR3 engine and an original ignition coil (50 years old!)

There's a screw in the top of the coil - I've heard this is to bleed/add oil? What kind of "coil oil" does one use?

No wise cracks about coil oil being next to the blinker fluid on the parts shelf......
Click to expand...

Not exactly "coil oil" it is transformer oil and is very much available. It is also used in those really big transformers like what the electric co. owns. It does 2 things, it is a dielectric and also cools the coils. On really big transformers they have to test it every year or so since absorbed water reduces the dielectric capabilities. Eventually it needs replacing. Last time I ordered that oil (for a 100kV electron beam welder) it came in 50 gallon drums. A bit much for an ignition coil! Group order maybe. Don't put regular oil in it is NOT even similar. Be careful with those old coils that fluid contains PCBs and other nasty chemicals.
 
70herald said:
Be careful with those old coils that fluid contains PCBs and other nasty chemicals.
Click to expand...
Which was my point, the original oil was PCB-based (which is why it lasted so long), but PCB oil has been illegal here for many years. Still a surprising amount of it in service though, it really was good stuff as long as it stayed next to wires and not next to humans.
 
Actually, they moved the coil oil over next to the muffler bearings.

Tom
 
The oil currently used in transformers is a "mineral oil". Don't know what additives it may have in it to make it temperature resistant.
 
Hello all,

apart from insulating, the oil is simply a heat transfer medium (In the coil it transfers heat from the coil to the case). You look at transformers and you will see fins or tubes for teh heat to dissipate. Transformer windings like heat less than oil does.

Alec
 
Transformaer oil is one issue, but may I ad that oils well that end well.
 
Back
Top