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norbert · 03-09-2006, 10:28 AM

Quote:

Originally Posted by ralley

The ignition wire can be attached anywhere between the battery and the post on the isolator. Again, it (the key switch) must be grounded to work.

can you post a typical switch schematic? i fail to see why a switch has to be grounded.....

ALANSD · 03-09-2006, 12:42 PM

You Have Not Gone To An Upgraded Alternator Have You? I Mean If It Is Higher Amp Rated Than The Isolator Is, That Could Be A Problem. I Replaced My Isolator With A 200 Amp When I Went To A 135 Amp Alt.

ralley · 03-09-2006, 07:46 PM

Quote:

Originally Posted by ALANSD

You Have Not Gone To An Upgraded Alternator Have You? I Mean If It Is Higher Amp Rated Than The Isolator Is, That Could Be A Problem. I Replaced My Isolator With A 200 Amp When I Went To A 135 Amp Alt.

Shouldn't make any difference in Chap K's situation. Even if one or more of the diodes in the isolator are blown, the alt should charge--the charge just won't get to the battery banks. There will be a voltage drop anyway--which is why charging systems (in maine applacations, anyway) should go around the isolator and directly to the batteries, so the batteries are not chronically undercharged. Sorry, Chap. K, this is not addressing the problem.

ralley · 03-09-2006, 07:51 PM

Quote:

Originally Posted by norbert

can you post a typical switch schematic? i fail to see why a switch has to be grounded.....

Most of the material I have is marine applications, and shows a definate ground (brown or black wire) from the ignition switch. While it may be in automotive applications that the ground does not run directly from the switch, there is certainly a ground in the circuit somewhere. I'll see what I can find tomorrow--I may need some adult supervision posting photographs.

R

ralley · 03-09-2006, 08:10 PM

I have just re-read your "what we know, and what we don't know" post. Do you know--is there juice anywhere in the fusebox? Back, front, anwhere? Is there juice to any stud on the battery isolator?

R

PeterH-350LE · 03-10-2006, 06:30 AM

The fuse block is not charred or burnt, they all look like that for some reason.
The Isolators purpose is only to separate the 2 batteries during charging. Yes, you can tap into one of the poles to get
either motor or coach power, but ignition is not part of the isolator function.
Below a picture of typical fusible link locations on the 454.

jimmickle · 03-10-2006, 06:55 AM

Are you sure that there aren't any fusible links down next to the starter? Most GM vehicles that I have worked on over the past 40 years had fusible links in the power wires coming from the starter. My first check would be to see if there is voltage at the terminal on the starter solonoid where the battery cable attaches.. If there is, check the other, smaller, wires coming from that terminal. See if they have voltage. I would bet on a problem right there. The fusible links should be in those wires within a few inches of this terminal. Please let us know what you find.

ALANSD · 03-10-2006, 07:42 AM

well my isolator idea was off the mark, but what about burnt wires to the starter somewhere? I had that issue a log time ago, killed everything with a wire burnt near the manifold. It caused intermittent problems before it burnt all the way thru and was hard to see...

ralley · 03-10-2006, 02:11 PM

Yeah--this is where I was going, albeit more slowly, with the battery isolator.

The circuit to the starting battery from the isolator also goes, by one means or another, to a post on the starting solenoid, and should be hot. One of the wires on the other post of the solenoid should go to the key switch. If it has a blown fusable link, the key switch cannot close the solenoid, causing the starter to do its thing. Easy to check with a voltmeter or a test light at the isolator and solenoid.

There should be measurable voltage between posts and ground with the key on start. Work back on any wire (toward the isolator or key switch) if you get no voltage on any wire, and look for broken wires, burned insulation, bubbles in insulation, or even friction tape in odd places. Tug on the wires a little bit and see of they stretch too much.

All of this presumes that the problem is either a blown fusable link or some other wire based problem, (which may not be correct) but it can't hurt to check thoroughly.

Ch Kent: Is any of this making sense? Do we need to do more praying for a good samaritan and and less figuring??

R

garry · 03-10-2006, 05:16 PM

Don't forget the netrual park saftey switch that I mentioned earlier.

The switch can prevent the starter solenoid to engage.
One test is to press the brake, hold the key in the start position and pull the shift lever thru all positions if the engine kicks over then the switch has moved out of alignment. This switch prevents the motor from starting if the shift lever is in gear.
Also make sure the wireing plug to the switch is connected since it may have been knocked off when working on replacing the dash.
The switch is (normally) mounted on the steering column about even with the brake pedal.

Garry

davidh · 03-10-2006, 05:21 PM

Gary you are correct BUT that switch will not kill all power to the dash.
Chaplain Kent How are you coming with the problem, I'm sure you have had other things going on, when you get the chance to try what I suggested over the phone let me know, I'm sure that will solve the problem, but if not we will go to the next step. keep me posted, you got my number.

Chaplain Kent · 03-11-2006, 05:50 AM

[quote=davidhChaplain Kent How are you coming with the problem,

I have the flu and Chummy's bathroom is not servicible at this time.

Chaplain Kent · 03-11-2006, 06:04 AM

Quote:

Originally Posted by ralley

I have just re-read your "what we know, and what we don't know" post. Do you know--is there juice anywhere in the fusebox? Back, front, anwhere? Is there juice to any stud on the battery isolator?

R

No juice anywhere to the fuse box, front or back. On the Isolator I have juice only on the far left terminal. The two breakers next to the isolator are both good. No juice at alternator.
Again Thanks for all the ideas and help, sorry I was out of it for a couple days, still can not stand up.

Chaplain Kent · 03-11-2006, 06:13 AM

[
Ch Kent: Is any of this making sense? Do we need to do more praying for a good samaritan and and less figuring??

R[/quote]
This has to be my favorite suggestion so far, thanks. My son works for Miller Beer and is trying to get one of thier truck mechanics to come over and see what he can do.

john hd · 03-11-2006, 06:15 AM

chaplin

sorry to hear you are feeling ill. hope you get well soon.

i have been following this thread, i certainly seems to be a fusible link problem. or a simple open in one of your circuits.

when you are back on your feet go get a test light that has a wire piercing feature. they are inexpensive and are really the only way to quickly trouble shoot bad fusible links.

you clip the ground to the frame and use the built in needle to pierce the insulation on each side of the link. voltage on both sides good, voltage on one side only = bad link.

if you cannot find one pm me and i will send you mine.

get well to you and chummy!

john

john hd · 03-11-2006, 06:31 AM

here is a pic of it to help your search.

i believe it came from farm and fleet, the pic explains its use...

john

ralley · 03-11-2006, 09:23 AM

Quote:

Originally Posted by Chaplain Kent

[
Ch Kent: Is any of this making sense? Do we need to do more praying for a good samaritan and and less figuring??

R

This has to be my favorite suggestion so far, thanks. My son works for Miller Beer and is trying to get one of thier truck mechanics to come over and see what he can do.[/quote]
Ch Kent: Stay in bed. By the time you are up again, we will have figured this out, provided ourselves with hours of mental exercise, and made a (sort of) plan for sorting out these problems for all in the future. We're having all the fun, and all you got was the flu!!

Hope you are back on your feet soon,
R

Jim & Susan · 03-11-2006, 09:41 AM

Chaplain, sorry you are under the weather. Hope you get to feeling better soon. I have a couple of suggetsions.

First, are we sure the battery is fully charged? The battery may be marginal or bad, or simply drained due to something associated with the dash changeout.

Second, I had a similar problem in a Mercury Capri in the 70's. If I jump into the way back machine and go back to the days of those poorly made '70's model American cars I remember having an intermittent starter problem similar to this. Sometimes it would start, sometimes no juice to the ignition. Turns out the problem was a skinned wire going to the starter that would occasionally ground out against the frame of the car and make it look like there was no power any place. Is it possible that you "nicked" a wire someplace that leads to a common power source for all the dead stuff?

I was having a litle bit of trouble following all the technical stuff above, but I worked on a friends car a couple years back that had a probelm with the running/head lights. We fiddled around with a bunch of stuff for a day or two then finally hit on "could it be a ground issue"? We grounded one the headlights directly to the frame and all was right the world. We simply made that new ground permanent and stopped trying to find the bad ground. As far as I know, it all still works.

Maybe that will help.

Jim

ALANSD · 03-11-2006, 06:34 PM

Hope you are feeling better Chaplain, sorry to hear about the flu, get yourself right first, the motorhome will be solved later.
The above ossue sounds like my problem when I had a slightly burnt wire..not thru completely so sometimes I had no juice anywhere other times it was ok. I found the inside of the wire burnt near the manifold a small spot that was almost thru the wore but not quite.
Anyhow you have lots of concerned folk here....gey well!!

Chaplain Kent · 03-12-2006, 05:59 PM

My neighbor and his father who builds hot rods and rebuilds vintage Harley's came over and spent some quality time with Chummy's wiring. After quite a few hours they gave up. Today my son and I took apart every wiring bundle we could find looking for a bad, loose, burned, or odd wire. After hours of laying on the ground, crawling around the engine and trying to get behind the tires, we found nothing. Every wire looks good and sound, every connection secure, no burns, no scorches, nothing even a little suspicious. We found no fuse able links!
Here's where we are still. The battery is fully charged. There is power to the battery isolator. There is power to the alternator. There is no power to either side of the fuse block. There is no power to the ignition switch. There is no power to the glow plug switch, horn, head lights or anywhere past that fuse block.
No one that has come to look at this has yet to tell me how power is getting to the fuse block. Everyone says there should be a larger gauge red wire than which there is. I have followed every wire into and out of that fuse block and I can not tell you where it's power comes from.
I'm tired, sick and ready for bed. Maybe I'll make a flower planter out of Chummy.