Oily Spark Plug, Should I Go Thicker?

My old Pentuim is getting 7 years on. Not Gaming and overclocking, but do you recommend I take off the heatsink and clean and repaste it with fresh compound? Do you find they dry up on a medium case desktop? I jknow laptops cook.

Thank You - Ken

- sorry guys about the mini hijack.
Yes, repaste. ...Well, if it's not too difficult. If you download a program called HWInfo, you can see hot hot your processor runs under load. PM me if you need details.
 
I would. Any oil on the treads I'd be worried about.

what people don't realize/know is that one of the main functions of the thread/body of the spark plug is to transfer heat from the plug and chamber into the head. Having a barrier between the threads and the head could cause a insulation barrier causing that plug/cylinder to run hot leading to pinging....that opens up a can of worms.
Well, you can overhaul the engine if you'd be worried about it. The OP has not mentioned any other symptoms or any signs of an overheated plug.
 
My old Pentuim is getting 7 years on. Not Gaming and overclocking, but do you recommend I take off the heatsink and clean and repaste it with fresh compound? Do you find they dry up on a medium case desktop? I jknow laptops cook.

Thank You - Ken

- sorry guys about the mini hijack.
I think you need to be in the computer section. We are talking oil on spark plug threads.
 
The engine feels a lot better after new air filter and plugs. It could be the filter though.

The oil loss is minimal. I don't have to top up. It stays close to full over the course of OCI.
 
As every PC overclocker knows, two bare metal surfaces don't have enough contact to effectively transfer heat. That's why very expensive (by weight/volume) thermal compounds are used. Oil will conduct heat through surfaces that otherwise wouldn't touch.

Oil is an insulator, so if it *did* prevent *all* metal contact, spark would diminish.
Motor oil can still conduct some electricity (it's not a perfect electrical insulator), and since the layer would be super thin in the spark plug threads area that will still allow some electrical conduction since the distance the electricity has to travel is a factor also.

But as mentioned, there is still the direct surface contacts that's going on when a spark plug is tightened in the head which ensures good electrical contact/conduction. The spark plug base area where it seats on the head is also a good heat and electricity conduction path.
 
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Re: Using Anti-seize or Oil on Spark Plug Threads

Not to do another "mini hijack" lol
but since you guys are talking about the subject ...

"NGK says their metal is a special material that will not stick to anything and no anti seize is recommended because of potential over-torquing."

"The nickel coating on most modern spark plugs provides added protection from seizing in aluminum cylinder heads and has made anti-seize less important in spark plug installations. Anti-seize can alter the tightening torque up to 20%, increasing the risk of breakage."

"From Autolite: We do not recommend the use of any antiseize products for installing spark plugs. Antiseize compounds are typically composed of metallic, electrically conductive ingredients. If antiseize compounds come in contact with the core nose of the plugs, it can lead to a misfire condition."

Doesn't seem like that heat transfer (or lack thereof) is a major concern. Having said that, some experienced mechanics still use anti-seize and some argue that no anti-seize recommendation is due to legal reasons and is to reduce or eliminate the liability of breakage (due to over-torquing) during installation. 🔧 🏳️
 
Figure showing heat transfer paths in a spark plug. You can even get some special paste to help the effectiveness of the thread path. Only 20% goes through the threads in the reference figure, but the amount changes based on the "heat range" of the plug. See other figures in the link.

https://www.denso.com/global/en/pro...e-parts-and-accessories/plug/basic/heatrange/

 
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