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Robyn
09-14-2006, 18:48
Recently I had an issue with the starter on my 94 Burb.
Now I have just rebuilt the 6.5 and its only been on the road with its fresh mill since early July.
I hopped in the seat the other morning and the thing would not spin very fast and also would not start at all.
Hmmmm bad battery??????
Jumped it off the big truck and it lit right up. The rest of the day it was slow in starting but would. Later that night even a jump would not get it going.
Bottom line the rebuilt starter had lost an armature and fried.
The local rebuilder made it good without so much as a whimper.
I took the time to run some line voltage tests to see what was happening and why the rig would not start even though it was turning. With the "brown out" that was happening because of the bad starter the harness voltage was way low.. (9V) and the Sol D would not lite the pump.
After replacing the starter I then rewired the rig with the starter relay as I did my other Burb. The rig starts better than it ever has and the harness voltage stays way up now. The factory is running all the current through the ign switch to run the solenoid. The voltage drop across that switch and though the line to the end where the Sol D lives is a butt load.
I do believe that I may have fixed the cold start in winter issue I had last winter. The voltage at the Sol D now stays about 12 when starting instead of 10.5 using the factory wiring to the Solenoid. (And this is summer weather)
I am reeeeeeeeely interested in seeing how this works for the winter.
It definately took a big load off the Ign switch.
Takes less than an hour to install the relay.
remove the right front tire and the inner fender rubber weather cover.
Remove the solenoid wire from the starter and extend it to the engine bay up by the right battery. Run a new wire back to the starter solenoid terminal.
I use Optima Batteries and hooked the new relay direct to the Bat + with a marine terminal and wired the other heavy terminal to the return wire to the solenoid.
The relays I used have 2 small terminal and two large ones. The large ones handel the heavy current and the small ones are, One to the battery ground (I used a marine terminal on the optima) and the other terminal hooks to the original solenoid wire that you extended to the engine bay.
Cost me all of $10 and less than an hour from getting the tools out to starting the thing up and that included replacing the starter too in my case.
Another case of poor engineering. All was good or at least workable while the rig was new and all the connections were fresh and new. At 265K miles the relay gives things a new lease on life and dramatically reduces the stress on the Ign switch.
Hope this helps someone.
Robyn

Bnave95
09-15-2006, 02:26
And I was going to comment on seeing if this would help our SOL-D during cold starts. When you first posted the key relay mod. You may have just mad the right mods for the issue:D
The wire that runs from the ecm to the SOL-D is on a relay. Will that work for me? Hard to tell, in that I have yet to have a cold no start issue. This will be my 3rd winter.

moondoggie
09-15-2006, 09:40
Good Day!

It's unfortunate Sol-D hasn't offered a variant of this simply brilliant (brilliantly simple?) idea. If this really fixes their well-known low voltage problem, they should be shipping relay, terminals, instructions, etc with each unit, connecting some easy-to-access rock-solid +12V point into the harness going into the Sol-D.

As it stands, we have to fiddle with the Sol-D to make it work if it gets a little cold out, switch FSD/PMD's twice a year, or do what I did: Mount a Standyne FSD/PMD where under-hood temps won't affect it. (I have no idea if my mounting will solve the Stanadyne FSD/PMD problems, but am unwilling to purchase a Sol-D - regardless of vehicle wiring, it ought to work at lower than 9V (5V IMHO) - 9V was a poor engineering choice. :( Very disappointing - when reports of the Sol-D unit began appearing, I had high hopes.)

robyn's idea would be great for all of us - the wiring in my 95's is IMHO generally inadequate. Driving the starter solenoid with an adequate relay instead of the ignition switch contacts is a terrific idea, whether you have a Sol-D or not. ;)

Blessings!

MTTwister
09-15-2006, 10:37
to Big time electrical Woes - in tech forum.

http://www.thedieselpageforums.com/tdpforum/showthread.php?t=24332

Robyn
09-15-2006, 15:07
On my Burbs I am connecting the relay directly to the battery via the top terminals on the Optima and using the side terminals for the cables. Cant get any better than this.
One could splice into the 12 volt line that feeds the Sol D and connect that to the feed lug on the new relay so when the starter is engaged the Sol D gets a boost directly from the battery instead of relying on the small wires in the harness to get enough current. As soon as the engine fires and the Ign start circuit is released the power will be quite ample to sustain opperation.
This would cause no harm at all and would assure an ample voltage supply during the critical start cycle where any issues are going to happen.
I noticed this morning on a cold start and it was in the 40's F but still cool that my 94 Burb started better than it ever has. The glow light went off and I hit the switch, the engine did not even make one rev and it was going. The starter barely engaged and the beast was rattling.
Robyn


Robyn

Bnave95
09-16-2006, 02:06
Ok now,who will be the first to offer this starter kit? I bet'sh some one will hit on your ideal,Robyn;)

tedtobler
09-16-2006, 05:15
From "Not that smart",

I read the description of how to re wire the starter and I am not that knowledgeable to understand some of the details. Is it possible to provide or email pictures and or drawings for this mod. I have a 1996 silver with 260K that I just replaced the starter in. Anything I can do to help this old girl that is cost effective I am going to try. So for us less than experanced pictures are worth a 1000 words. Feel free to email me. ted2020@hotmail.com.