94 chevy 2500 diesel

[thomaslc]

while driving everything shut off as if the key had been turned to off. reset the key and in started right bacl up and ran fine. Next time I tried to start it, turned the key to glow plug and nothing, reset key and everything was fine. Next time turn the key to glow plug warm up then tried to turn engine over and complete electrical loss, no gauges, no powere windows, no radio. Reset key and tried again same issue except no glow plug went immediately to no electrical power. During one of the attempts I heard a firm clicking near the middle of the dash or firewall not sure which. Both batteries are fully charged. Wondering if there is a solenoid (clicking sounded suspect) problem or maybe the key switch. Don't know where to start. Any help would be appreciated. Thanks to all

 

[ak diesel driver]

I'd be suspecting ign switch. Not the key part but the electrical switch down lower on the column

 

[thomaslc]

Thanks AK, do you know of any way to test that switch before pulling it?

 

[ak diesel driver]

It would be hard to test unless it fails completely. Alot of times it will show continuity but when you put a load on it it won't carry it.

 

[MrMarty51]

Welcome to TTS thomas

 

[thomaslc]

It would be hard to test unless it fails completely. Alot of times it will show continuity but when you put a load on it it won't carry it.

so, I went out this morning, turned the key on with no response, wiggled the passenger side battery positive cable (with the red smaller wire) it now works as it should, started several times with no issue. Confusing since the cables were tight and the battery was fully charged before I touched the cables. Scratching my head at this point. Is that a fuse link in the red wire and is it possible that it could be the intermittent culprit?

 

[jrsavoie]

so, I went out this morning, turned the key on with no response, wiggled the passenger side battery positive cable (with the red smaller wire) it now works as it should, started several times with no issue. Confusing since the cables were tight and the battery was fully charged before I touched the cables. Scratching my head at this point. Is that a fuse link in the red wire and is it possible that it could be the intermittent culprit?

Yes
It's a fusible link.

It's never a bad idea to upgrade the cables on about anything GM or any other manufacturer. They're all built to the minimum standard to save a bean or 3.

Also upgrade the wire going to the load center.

 

[Will L.]

Do you still have the horrible side post batteries. If so- do the bolt mod for now and plan out getting new larger battery cables (gm is cheap with copper) and get them top post. And obviously the new batteries will be top post. I wanna say group 31/78 but verify that.

 

[jrsavoie]

I never had an issue with the side posts.

I run group 34/78 dt, Dual Terminals

I've always used -1-1/4" long Allen screws for the battery bolt mod. Make sure the screws are flat ended. Pointy screws will strip.

 

[Will L.]

34/78! That’s the numbers my brain was short circuiting on! Haha.

 

[jrsavoie]

If somebody, not in the know reads this thread the battery bolt mod requires 3/8-16 thread bolts or Allen screws.

If you use an Allen screw, it has to be flat on the ends. I like stainless or brass.

I haven't had issues mixmatching those metals. I usually use grade 8 nuts on.a stainless Allen screw.

Stainless on stainlesscan gall.

Bolt Depot - Set screws, Allen, Cup point, Stainless steel 316, 3/8"-16 x 3/8"

boltdepot.com