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94 B4000 no start (read whole post)

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Old Jan 30, 2026 | 01:55 PM
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Default 94 B4000 no start (read whole post)

Howdy,

I am currently at my wits end. The old b4000 required a new slave installed which was completed and bled of. During this process a new master was installed as well (the original wouldn't mate up correctly with the new slave). There were other installations done but have nothing to do with the drive train.

Current problem is a "click no start". The relay clicks on, transfers power to the starter at 12v constant and 12v ignition. Ground works as it had come come loose nuking the whole system. Installed a new starter (why not better than 30 some year old one) and it produced the same result. Relays arw cheap enough at this point so that might get replaced as well.

My only option now is bypass the clutch wire harness.

Am I missing anything? Is there a postion sensor somewhere that could have been knocked loose with the trans installation?

Thanks in advance.
 
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Old Jan 30, 2026 | 01:55 PM
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Welcome to the forum
 
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Old Jan 30, 2026 | 02:06 PM
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The very first thing to check is the battery condition only by way of a "LOAD TEST"! There are other old-school methods but those do actually require that you have the proper battery testing equipment and really only work with conventional wet batteries. The age or that it has 12.50 is not any indication of than batteries state of current health.
Also this a great time to check the 4 battery connection at the battery, the grounding source and the cable to the starter at the starter.
 
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Old Jan 30, 2026 | 02:07 PM
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Oh, I forgot that, the battery was replaced with an 850 CCA.
 
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Old Jan 30, 2026 | 02:20 PM
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Originally Posted by Yotadrvr
Oh, I forgot that, the battery was replaced with an 850 CCA.
Ok but did you load test it before you installed it or at the retail store before you left.
I hear this statement so often from customers and a quick load test finds that there towed in vehicle only needed a replacement battery.
So I guess the better answer would have been did your starting problem happen before or after the battery change?
And if after you should at least do a battery voltage check and if the battery is 12.50+ volts then a quick voltage drop test to see how much it drops when you attempt to start the engine.
Until you first completely rule out the battery it all about guessing....... what the next step for checking should be.
 
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Old Jan 30, 2026 | 02:36 PM
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Fair enough. I'll have a gander at that option shortly. I'll be some pissed if that's the problem.

Also, the vehicle started prior to the slave swap out. It could start in gear or out of gear. It had to start in gear to drive as it wouldn't shift. Hope that helps as well.

The battery was swapped do to being frozen (buldged out) and wouldn't hold a charge based on what my multimeter was showing me.

Aside from a load test on the new battery, everything seems to be checked off.
 
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Old Jan 30, 2026 | 02:45 PM
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I wouldn't worry and if it is the battery hopefully you have a warranty and can either get it pro-rated or exchanged. Not to mention save you a lot of work to track down an electrical problem.

It is my policy regarding any customer that has any issue that relates to electrical to first and always check the battery condition and the 4 connections for good continuity before the customer leaves. And most of the time I try to do the test in front of the customers while explaining what I am doing and what I hope for them what results will be.
 
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Old Jan 30, 2026 | 04:45 PM
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Load test on battery is good.
 
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Old Jan 30, 2026 | 04:56 PM
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well crap... time to do some by-passing of the staring and ignition system start components unless our resident "B" series expert member has a DIY thought? He will be around a little later?
 
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Old Jan 30, 2026 | 04:57 PM
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Excellent! Thanks for your help
 
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