Thread: Battery Master Disconnect Switch

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I'm a new poster to this forum,
I put a Master Disconnect Switch (MDS) rated at 130 amps in my 56 Chev 327. Due to some carb problems, it flooded and when I was grinding on it for 20 - 30 seconds to clear the engine, the car suddenly lost ALL power (not even a dome light). When the car had completely cooled overnight, all power was restored.
I must have exceeded the current duty cyle of the MDS and I've asked around and people are telling me that the old Delco Remy starter on a hot engine could draw as much as 300 amps. Any MDS experts out there who can tell me what the specs are on an MDS that will handle a situation like this? And, what kind should I replace this one with?

Tubaman

The easy part is WELCOME! Best car forum on the net, right here!!

While I don't have a disconnect in mine, I've seen a few that can handle some high amp ranges. Do some reading at Summit Racing dot com and - or Jegs, review the spec lists and see if they've got one that'll fit your needs. Some batteries out there have 500 cold cranking amps (or more!) so you'll need to be aware of what your battery can produce. Also, try not to crank over an engine for more than 10 - 20 seconds at a time, they develop a lot of heat with all those amps!

Write back and let us know how you make out.

I'll add my welcome as well.

Many, if not most of the battery disconnect switches sold in the US are made by Cole-Hersee, even the Longacre Racing versions. Their amp range goes way up !!

Here's their web site - choose one then do a search: Battery-Related Products | Master Disconnect Switches | Cole Hersee - Littelfuse

If I recall, mine is 175/1000, but CRS often takes over but 175/450 should work

Welcome tubaman, you didn't say why you have the switch on the car BUT if its for racing you'll need one that cuts ALL the electric to the car including the altinater. should have 4 posts on back.

welcome to chr tubaman