Newer Grey FSD bites the dust!

[jrsavoie]

I did some looking and see lots of pictures of the one you like however most have changed the fin cooler design, perhaps cutting the mounting tab and welding it in a more user friendly spot. There are lots of fin cooling plates on ebay.

I have riveted or screwed a piece of aluminum angle on heat sinks to make them easy to mount the way I like them

 

[FellowTraveler]

Just so everyone knows I only though the FSD was failing because of dielectric jelly I used to seal the connection getting into the socket and on the resistor causing the problem, lucky it did not damage the resistor etc.

 

[great white]

I pack my connections with Grote Ultra seal electrical grease:

Works good, lasts long time, designed for the job. It's what is in my FSD cavity right now and it lives in a salt/water blasted location. No issues.

I use it on all the connectors I touch. Almost mandatory in Eastern Canada in it's salt leaden environment...

 

[FellowTraveler]

I pack my connection with Grote Ultra seal electrical grease:

Works good, lasts long time, designed for the job. It's what is in my FSD cavity right now and it lives in a salt/water blasted location. No issues.

I use it on all the connectors I touch. Almost mandatory is Eastern Canada in it's salt leaden environment...

Any idea why dielectric caused issues in my FSD socket?

 

[great white]

Any idea why dielectric caused issues in my FSD socket?

Shouldn't.

Dielectric is by it's very nature non conductive and non corrosive. Should do the same thing as the Ultra Seal. I use the Grote stuff because it's advertised to be 25% less conductive than comparable dielectric products and it's a bit thicker and "tackier". Temperature range is similar between Grote and most dielectrics, so overheating and running out shouldn't be an issue.

My FSD is packed with Grote, then the resistor is installed, then cavity is filled with Grote and finally the connector is pressed into the whole mess.

Perhaps you used and off brand dielectric that was quite as "dielectric" as it should have been and allowed some conductivity on the resistor card traces?

I know I have had green "futz" corrosion build up under a resistor card before and it messed things up royally when it started bridging the traces. I find that anything that touches the card that is even remotely conductive causes all kinds of strange issues.

That's why mine is packed solid. No air, no water, and the Grote grease has corrosion inhibitors in it which equals no corrosion anywhere in the cavity.

last time I talked with Heath (which was, admitted, a fairly long time ago) he said he was going to start shipping his PMD kits packed with grease in the cavity. Whether he actually does it now or not I do not know....

 

[hookedup50]

This dielectric grease topic, makes me wonder if my strange electrical issues are being contributed by my use of dielectric grease.

 

[FellowTraveler]

I was going stir crazy never had dielectric be an issue so never considered it then when I ran out of ideas I decided to investigate the FSD plug cavity saw lots of gel that had gotten in there so decided to remove the unit and clean it thoroughly with denatured alcohol then electrical contact spray afterwards everything is back to normal. I just have the gel around the weather pac sealing gasket now!

 

[great white]

I would say the dielectric on the resistor card may be suspect as the actual diagnosis. Proper dielectric should not behave like that.

I would suggest you fill the cavity and see if the problem returns. If it does, at least you know it will recover with a cleaning and there's not another issue waiting in the wingsmto bite you on that lonely dark stretch of highway....