cap and rotor question

[Digital2k2]

hey, I'm gonna put a new dist. cap and rotor in my truck tomorrow along with new wires.

the wires came with a little pack of dielectric grease and I was wondering if I should put some on the rotor and contact points on the cap?
my current ones are pretty rusty looking, and I thought this might help keep the new ones from getting in that condition.

has anyone else ever done this or is this a bad idea I've got?

btw, it's an 89 toyota 4x4 with the 3.0L V6

 

[Dan4510]

Dont put it on the rotor and cap. Use it only on ends of plug wires where the attach to the cap or to the plug.

It seals the connection electrically and physically from contamination intrusion.

Dan

 

[Boeing 757 Pilot]

I always put the dielectric grease that comes with the new wires. I believe it is supposed to keep the moisture out and makes a better contact.

When I changed the wires on my wife's Acura, I bought a set of 8mm Borg Warner wires from Pep Boys. Just out of curiosity, I measured the resistance of the factory wires. You will be amazed just how bad the factory wires are. The factory wires measured between 3-5 ohms.

And the new wires had almost none. With a new set of NGK's and the Borg Warner wires.....this Vtec screams

 

[W.T.McGlynn]

Don't do it.The Dieleltric Grease
is to prevent the Spark plug boot from sticking to the plug next time you take it off.Take a small screw driver and put some inside the plug cap.Good Luck !

 

[Darryl]

Yes, Yes, Yes....Yes put a small dab of dielectric grease on the contact pins of the cap and the the rotor center/end points.

This is SOP on all cap & rotor, as well as sparkplug boot installation.

Look at any shop manual and it will confirm this. I have been doing this since High School Autoshop(19years ago) and my cap/rotor have always looked great, even after 50,000 miles.


Darryl

 

[Digital2k2]

I just checked my haynes manual: "Apply a small dab of silicone lubricant to each terminal before installing the cap"

*confused*... would silicone be much different from dielectric grease?

 

[eljefino]

There is supposed to be "air space" between the rotor and cap contacts. So there will be a spark there, guaranteed. The material the contacts are made of can take it; personally I prefer brass-- not often found on the cheaper Wells brand ignition components.

If you put grease on these contacts, it would burn off pretty fast. I feel the grease is for the plug wire ends.

 

[john_ertw]

The grease came with the plug wires for a reason (and it wouldn't be to protect another company's cap & rotor).

 

[Digital2k2]

well, I replaced the cap rotor and wires.

now when I give it a bit of gas the idle will stick higher for a second and is sporadic...

checked to see if I knocked any vacuum hoses lose, couldn't find anything. Could I have done something wrong, or maybe the TPS is acting up now? the only luck I seem to have ever is bad

 

[TC]

From several authoritative sources:

From Crane Cams: "To help seal against moisture and to allow easy future removal, apply a small amount of silicone dielectric grease inside the spark plug wire boots." http://www.cranecams.com/pdf/90001001b.pdf

From Pep Boys: "Before putting the new spark plug wire on put some dialectric grease on the end of each spark plug to prevent corrosion"..."Simply put the new rotor back in and then bolt on the new distributor cap. Put dialectric grease on each terminal of the distributor cap and replace the spark plug wires."
http://www.pepboys.com/learning_center/car_care/articles/svc_ignition.html

"Step 14: Install the distributor cap." (When retrofitting a Mallory electronic ignition module to an old distributor, it doesn't mention applying grease to the cap internals or rotor.)
http://www.centuryperformance.com/mallory/techfiles/MA0838B_UniliteConv_PN501.pdf

For the Taylor Vertex Magneto (distributor): "9. Lubricate center rotor electrode with one drop of light grease and graphite mixture periodically."
http://www.taylorvertex.com/Magneto_Instructions.pdf

MY CONCLUSIONS, PER THE ABOVE:
1. "Silicone grease" and "dielectric grease" are one-and-the-same.
2. Lightly grease inside the spark plug wire boots and inside the distributor cap connector cups (the outside of the cap) to reduce corrosion and allow easy removal of spark plug wires at both ends.
3. Lightly grease each spark plug tip.
4. Placing a dab of grease on the rotor's center electrode (but NOT its tip) MAY be appropriate since this is a contact-wear point.
5. NONE of these firms mentions placing grease on the rotor tip, nor on the corresponding cap electrodes inside the cap. I suspect these are meant to be grease-free air gaps.

[ June 24, 2004, 06:04 PM: Message edited by: TC ]

 

[mechtech]

Ford used to recommend putting di electric grease on the rotor tip. I believe it was to help with RF emmissions. Standard stuff in the shop.