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mayco · 06-27-2017, 12:17 PM

Awww thanks buddy! As always on the road we are having fun around every corner so far. Our next stop is up in the mountains a bit at Golden Gate Canyon State Park. Should be really fun. First time for me driving the rig up to that elevation so hold on! Not worried at all about going up its coming down that should be interesting. Gotta do it eventually right? This old Allison should keep us at a safe speed.
You sound like youre livin the life there Richard!!!! Good on ya! We have to do it while we can, especially in these old beasts. You came in in conversation yesterday, cant remember the context.
We gotta cross paths here eventually!!!!!!!!!!!!

Well, cleaned the ground strap to the motor to frame, both ends.....tested with my spare meter......no joy yet. BUT! Ive sure got a lot of shiny new ground connections so no wasted time in doing what Ive done so far. Ill find it....eventually. Ill keep plugging along and in the mean time Ill just drive with my lights on all the time, it keeps the voltage at a safe reading. Its got me puzzled though. Alt is putting out plenty of juice.....

Any more ideas out there please send them my way. There mat be more than one strap to the motor to frame....if I find it Ill clean it up.

Could the isolator be a part of this??? I could bypass it I think. Head scrathin here.

mehes · 06-27-2017, 04:19 PM

Mike I don't believe your regulator has a separate 'Sense' lead as some other regulators have. It just reads voltage from the 'Battery' lead which no doubt comes from somewhere under your dash. It might be interesting to get some voltage readings at your isolator, all three leads to ground and somewhere under the dash or fuse panel with the engine running. My long-shot theory is you have some voltage drop from the actual battery to the general wiring under the dash. If this is so your voltage regulator would be reading the lower voltage under the dash causing it to put out a higher voltage on the lead going to the isolator and batteries.You may be cooking your house batteries as well as the engine start battery. If this isn't the case at least you will have some more information that may solve the problem. Happy hunting.

mayco · 06-27-2017, 05:30 PM

Quote:

Originally Posted by mehes

Mike I don't believe your regulator has a separate 'Sense' lead as some other regulators have. It just reads voltage from the 'Battery' lead which no doubt comes from somewhere under your dash. It might be interesting to get some voltage readings at your isolator, all three leads to ground and somewhere under the dash or fuse panel with the engine running. My long-shot theory is you have some voltage drop from the actual battery to the general wiring under the dash. If this is so your voltage regulator would be reading the lower voltage under the dash causing it to put out a higher voltage on the lead going to the isolator and batteries.You may be cooking your house batteries as well as the engine start battery. If this isn't the case at least you will have some more information that may solve the problem. Happy hunting.

The volt meter on the dash is corresponding with the meter reading at the battery. Ill test a couple spots under the dash and get readings from the isolator. The chassis battery is reading normal while sitting and the engine off. Coach batteries read normal while plugged in, maybe I should unplug and let them sit then take a reading. I was thinking about removing the coach batteries from the isolator and then moving my chassis battery connection over to the alt lug. I think that would essentially bypass the isolator, just to take it out of the equation. Ill wait on that. I'm starting to think on the "load" side of this thing. Like the reg is trying to keep up with a load of some sort.....heck I don't know!
Ive got several days before we need to move on from our present spot.

mehes · 06-27-2017, 05:52 PM

Sorry Mike I thought you had a lower voltage at the dash. More readings can't hurt. We're not giving up on this.

mehes · 06-27-2017, 06:05 PM

Mike, second thought. Get a reading at the dash with the same meter you checked at the battery in case they aren't calibrated the same.

bkahler · 06-27-2017, 06:06 PM

Quote:

Originally Posted by mehes

Sorry Mike I thought you had a lower voltage at the dash. More readings can't hurt. We're not giving up on this.

Ditto, I was thinking the same thing about the dash meter.

Typically going through the battery isolator you are supposed to loose about .7 volts. So if your alternator output was reading 14.7 volts at the isolator then you should be seeing about 14 volts at the battery. You're obviously getting way more through the isolator which tells me it's probably working correctly.

If as mehes says your regulator does not have an external sense wire then what you're experiencing makes even less sense. If it's sensing the voltage at the alternator output then the regulator should be dropping the alternator voltage quite a bit so that it would see around 14.5 volts or so and you should see even less voltage at the battery.

Personally I'm not convinced your regulator is any good

bobmiller1 · 06-27-2017, 06:56 PM

OK.....so I'll throw my 2 cents in....Is there openings in the top of the battery to measure the specific gravity If each cell ???? You may have a bad cell in the battery causing your issue or you have a bad voltage regulator. I have had both problems amongst others in my work truck which is the same vintage.....Regards, Bob

mayco · 06-27-2017, 07:01 PM

I would agree about a bad regulator except that the new one is behaving exactly as the old one was. Its brand new out of the box, I know that doesn't mean it's good, Nippon denso. Could be bad but odds are slim...surely not impossible.
Its hotter than heck here too which doesn't help trying to work outside.....I'm a sissy and I don't care

. I'm going to go ahead and get readings from the fuse block and at the isolator and see if something clicks. Now it's my understanding that a bad battery or one that's about to go can cause this overcharge reading also but my battery is holding a good charge at 12.6 to 12.8 for days. Checked fluid in all the cells and its aok. I also haven't cleaned up all the terminals on the coach batteries yet though I wouldn't think that would be related to the chassis battery. My coach batteries are older than the chassis and they're condition may be questionable. That's why I was thinking of removing their lead from the isolator. I know they shouldn't affect charging if the chassis battery but WTH, easy enough to pull the lead off the isolator just to eliminate them from the mix. I haven't done a parasitic load test but since my battery is staying up I doubt that's a problem.

Keep any and all ideas coming fellas I certainly am grateful! Hope y'all know that!

mayco · 06-27-2017, 07:06 PM

Thanks Bob, yes I can open up the top of the cells but I don't have a hydrometer (?) cell tester with me. I could pick one up tomorrow. We are renting a car tomorrow for errands.

Regulator brand new OEM just installed, but acting the exact same as the one I removed.

PeterH-350LE · 06-27-2017, 07:36 PM

Mike, I like your Idea of disconnecting first the coach batteries from the Isolator and then the motor battery and see if it changes anything
What are your readings at the three isolator terminals with the engine running ?

mayco · 06-28-2017, 06:02 AM

Thanks for jumping in Peter. I'll get readings at the isolator this morning, gotta wait till more folks are awake around the campground before I start the motor.

centennialman · 06-28-2017, 06:10 AM

Good luck Mike! You guys be careful driving up in the mountains!

mayco · 06-28-2017, 06:18 AM

THANKS STEVE!!! We are sitting outside having our coffee right now and we're just talking about you two!!! How bout that!

centennialman · 06-28-2017, 07:01 AM

I wondered what the ringing in my ears was....tell Lynn hi!! I am on the road up to Steamboat tomorrow....Hector is pacing and knows it's time for a trip in the Airstream.

mayco · 06-28-2017, 07:06 AM

GREAT! Safe travels!

mayco · 06-28-2017, 09:29 AM

Well I doubt this is good. Removed both house and chassis wires from isolator and checked voltage on the alt lug, got 19.8 volts. So, does this mean it's the alternator? I'm assuming it does, no load voltage. I guess I should check voltage at the back of the alternator first? I'm getting a bit above my knowledge on alternators and regulators. I know what they are supposed to do of course but not sure how an alternator could be pumping out that voltage and where does the regulator come into play. Ive got a new alt and tools to get it on.

Any more tests you fellas would do before I change the alternator out?

Smartstream · 06-28-2017, 11:42 AM

Mike electricity is not my strong suit but my understanding is if you get a disconnect in the output between the alternator and the battery while running, the output voltage will run away until the alternator cooks itself. With that in mind it is the resistance in the battery, level of charge, and the regulator that controls the actual output of the alternator.

With your situation I would guess the problem is not the alternator but the regulator or somewhere in the wiring and connections. Since you changed the regulator and still have the problem that leaves wiring and connections. You might consider using a long wire to connect your meter to a single ground point while you check voltage at the batteries, isolator, dashboard and anywhere else you might check. That would eliminate getting readings affected by varying ground conditions throughout the coach. It would be interesting if you could disconnect the alternator output and run a wire directly to the battery eliminating everything in between.

Again it's not my strong suit just kind of thinking out loud.

PeterH-350LE · 06-28-2017, 11:45 AM

Edit, just read Dans post . You may want to connect either battery first to the isolator and see what voltage you get.
Here is my original post, something I would do to get the alt out of the loop.:
Go for it Mike, swap the alt, it's not really all that bad if the engine is cold, on the gasser you can reach everything from the top after removing air cleaner. I just put a thick blanket on everything and get on it.

bkahler · 06-28-2017, 12:22 PM

Peter, Mike's rig is a diesel so I don't know how easy/hard it is to change the alternator but I've not found it to difficult to change a 454 alternator on the side of the road. BTDT!

Dan, I don't know if this applies to alternators in use today but I remember being able to run vehicles with no battery connected as long as it had an alternator. If your vehicle had a generator (remember those?!) the engine would die as soon as you disconnected the battery. What I don't know is what effect not having a battery in the circuit did for the voltage regulator. I.e. did the alternator or regulator burn up. On the Spitfire race car when the battery was dead we would push start the car at the start of a race session. With an alternator in the car as long as the car didn't stall she could run the entire race.

As far as your regulator being new that doesn't necessarily mean it's good, or it might have been good out of the box and then died. Electronics can suffer crib death which is new parts will work for a little while then fail. Generally if a new electrical component lasts for more than a few days or months it will likely last for years.

The fact that you saw 19 volts at the isolator when no batteries were connected to me indicates the regulator isn't working. Per mehes comment about the regulator sensing the alternator output at the alternator then I would think the the voltage would have been at about 14.5 or so at the isolator.

mayco · 06-28-2017, 12:40 PM

Thanks so much you guys.....I'm not celebrating yet but I think I nailed the problem. Got the motor cover completely off and was preparing to get a test on the back of the alt. I inspected the 6 pin connector on the regulator again and as I lifted on it one of the wires on the harness side popped right out of the connector. It obviously had come disconnected from the inside metal female connector inside the 6 pin. Got out my wiring diagram and it is the wire labeled "wiring harness" in the picture. I cut and spliced it through outside the connector and said 3 or four Hail Marys. Going along with wha Dan said about resistance, I think that solved the problem. Started it up and now getting 13.2 or so at idle had Lynn rev to 2000rpm here in the campground and never got above 14.7.
Haven road tested yet but I think we have solved the problem.

Sincere thank you to all of you guys, it really "at" the regulator just not "in" the regulator. Need to road test but the numbers are good especially compared to what I was getting.
Tested at isolator and it was about 14.8 then tested at the battery and it was at 13.2 to 14.7 when reving. I think we got it guys!!!!!!!!!!!!!! Still not celebrating till I get it up to 2800rpm... thanks again for your help on the road here.

Other than that, having a great time in Colorado!!!