Hi all - first post here.Just got an '84 Allegro. Not sure what it is - NADA doesn't show a 31 footer but my insurance company does. The model number on the tag under the dash stars with M31 so I'm thinking that's what it is. It has a bedroom with twin beds in the back which I have not seen before. It popped up on Craigslist for about the price of the tow to my house so I couldn't turn it down. The 454 in it needs rebuilt or replaced, which is no big deal for me (yes, I know it needs to come out the driver's door).It had been sitting for 5 years. It was properly winterized and *almost* everything seems to work. With the engine being the #1 priority, there are a couple of other things that would be nice to remedy while I'm inside working on the engine.First, lights are pretty dim. The more I turn on, the dimmer they get. When the furnace blower turns on, the lights noticeably flicker. Now, all 3 batteries are beyond gone. None hold any sort of charge. I'm wondering if the dead batteries have anything to do with the apparent struggle the converter is having? The 6.5kw generator won't turn over either (though I was told it works) - clicks like when you have a low battery.Second, the motorhome has 2 furnaces. A Suburban NT-30 in the front and something smaller in the rear (Suburban as well, but can't find a model number). Front furnace works great and it's pretty apparent that the rear furnace is necessary to keep the back bedroom warm. It doesn't work. Fan runs, I have gas to it. It doesn't try to fire. No clunk from the gas solenoid; no click from the ignitor. Where do you begin troubleshooting? There's a lot of info on the web, but I'm not sure what pertains to something of 1984 vintage.Beyond that, the thing was nicely maintained and is nicely appointed. I look forward to firing up a fresh 454 and getting on the road with it.Thanks in advance for any advice!

The converter in something of that era is really a pretty poor performer. You'd be much better off with a new 3 stage unit and your going to need new batteries anyway so.. ;)

ScottG wrote:The converter in something of that era is really a pretty poor performer. You'd be much better off with a new 3 stage unit and your going to need new batteries anyway so.. ;)Thanks! It does not appear as if this one charges the engine battery either. It just does the coach batteries. Seems like an opportunity to fix that, too. Not sure if it's the batteries coming back up a bit or not, but tonight things are much brighter. But not where I'd like it to be. The dark paneling of the day sucks up a lot of light, but I'm thinking maybe LEDs that draw less juice and are a bit brighter might do the trick Dunno. I got the rear furnace to fire. I removed the cover from the front and it fired. I replaced the cover, it got up to temp, but wouldn't fire again until I removed the cover. Air flow problem I guess. I'll have to mess with it. There is a sizable hornet's nest in the intake outside. I've read that they're pretty sensitive so I'll clear that out. It's a smallish furnace with just 2 outlets. If I could tap in another it might do it, too.

Better start with all new good batteries. Bad batteries can cause a variety of symptoms.The furnaces need good air flow for the igniter to fire. Batteries again.

If it's the converter I think it is, it charges at 3 amps max and always has to have batteries connected to keep the 12V clean. Any idea how old the batts are? If the sides are bulging then they're sulfated and past their prime.Scott

No idea how old the batteries are. I know the rig has been sitting since 2008 when it was towed to a yard when the engine failed. It was towed a couple of other places since then, but apparently never put to use during that time.Batteries have to be well past their prime at this point. I'm going to take one out of my limo (another hobby of mine) to power the chassis. The coach batteries will have to wait for now.I told my brother that it's slowly waking up. After 5 years (possibly more) of sitting the systems are starting to come online. It's been plugged into my house for 48 hours now. I've been sitting in it out in my driveway for hours now to make sure both furnaces are cycling as they should be. They are. The rear one has decided that it's happy with the air flow now. Temps are dropping quick here in the Northeast. I'm going to let the furnaces run to see how they do.Thanks all for the replies. I will have tons of questions about this thing. My main objective is to get it mobile for tailgating and other nearby events. If I can get it to a point where it's reliable I may venture further......

Converter and Furnace Questions | Good Sam Community

turbojimmy
Explorer
Dec 24, 2013
No, I haven't done anything to it. I assumed the batteries were no good because it had been sitting since 2008. It had been towed around to different places, but never started or plugged in.

It was delivered here on Saturday and I've had it plugged in ever since, running both furnaces (once I got them both working). The previous (original) owner must have cared a lot about it. It was really nicely maintained. After sitting for so long, though, it needs some TLC.

It has a "Jet Ride" air suspension which is neat but apparently there's a leak in the left bag. I need to hook my car up to it occasionally to get the compressor to run so I can pump it back up. It looks like it's going to tip over!

So, like I said - long to-do list but it's a fun project. It's a time machine.
turbojimmy
Explorer
Dec 29, 2013
Quick follow-up....

My brother had a new, deep-cycle Group 27 battery in his trailer. While he was at work, I "borrowed" it. When installed in place of the 2 dead batteries, things started to look a bit brighter. Lights are brighter, furnaces run faster, generator actually turns over (and starts, and runs, and makes electricity!).

With both furnaces and lights on, the battery is depleted faster than the old, stock converter can charge them (as indicated by the monitor panel).

Question is: stock converter was 40 amps. Should I go with something close (like a 55 amp PowerMax @ $120) or bigger? I plan to replace both group 27 batteries with new ones.

EDIT: it has a "deck mount" converter (not integrated with the panel) so it's easy to swap out with whatever I'd like.
wolfe10
Explorer
Dec 29, 2013
I would be quite surprised if your are using more than 40 amps of 12 VDC unless you have an inverter pulling power. A couple of ights, furnace fan on some, but not full time and occasional water pump just will not average that much.
jhilley
Explorer
Dec 29, 2013
I would go with a 55 amp converter. It will give you a little more capacity and not much more cost. Batteries shouldn't run down while on shore power.
turbojimmy
Explorer
Jan 28, 2014
Okay - I went with a 75 amp. For the incremental cost between 55 and 75 I figured I'd just go that route. The 45 amp stock unit - even when it was performing as it should - was definitely at its limits with the 2 furnaces, all the lights, water pump, etc.

It hasn't arrived yet, but I'm afraid the old one is ruining my brother's battery in the meantime. You can hear the furnace blower slow down when you turn on a light or when the other furnace comes on.

The newer units all seem to have the same charging strategy: 3-5 amps charge rate and 3 modes of "smart" charging.

With regard to the 75 amps vs. the stock 45 amps @ 12V, from what I've read it doesn't really matter if you have a lot more capacity unless 1) you start to draw current beyond the stock wiring's capabilities and/or 2) you are drawing more amperage than your generator can supply. I don't have either of those scenarios.

I went to the 75 amps to have headroom for a 12V A/V system that will have its own distribution panel and fuses. I'll split the feed from the converter and let the stock wiring feed the stock panel and stock accessories. The generator is 6500 watts. At full bore, the 75 amp inverter would draw 3 more amps than the stock 45. So I think I'm good there.

And also included in the original topic: that rear furnace continues to function properly. I ran out of propane today but installed a SturgiSafe kit so I could add an external tank and keep it warm while I'm wrenching on the engine.
Old-Biscuit
Explorer III
Jan 28, 2014
Plan on buying your brother a new battery.......you are killing it with that old converter (lack of being able to maintain charge) and by drawing the voltage down low repeatedly.
turbojimmy
Explorer
Jan 28, 2014
Probably, yes. It's a deep cycle marine battery but they can only take so much.
turbojimmy
Explorer
Feb 01, 2014
FedEx brought the converter today so I popped it in. It's half the size and 1/4 the weight of the original. WOW what a difference. Furnace blowers blow with so much vigor, lights are bright. The old wiring isn't exactly where I needed it to be, but it was close enough to get it hooked up.

And, the info panel reads accurately. I guess it depends on the proper voltage to work? I noticed when I first got the RV and the batteries were dead that each position read about 1/4 tank (water, gray and black)even though I know they're empty. When I put a good battery in it, they all read empty but the propane still read between E and 1/4 even though that's empty, too. And the battery never read FULL even though the converter was plugged in. Well, propane shows E and battery shows F now.

At first I thought it wasn't working because it wasn't making any noise. The other one buzzed quite loudly. It's getting warm, though, so I know it's working. I can smell that distinctive smell of electronics getting warm for the first time, too.

One more thing to scratch off the list!
wa8yxm
Explorer III
Feb 01, 2014
Some facts: Many older rigs have a Magnetec 6300 line, this only charges the batteries at a few amps, and it never stops, even when the batteries are full.

I have a newer rig with a Progressive Dynamics 9180 with the optional charge wizard, This is equal to the 9280 with dongle, These are 3-stage plus converters and are, far as I can find, the very best there is. Also PDI is a US company. I have driven past the plant. (Many times, grew up less than half an hour from there).

I have a mixed battery system on this rig, 3 or 4 Group 29's and a pair of GC-2. now when the GC-2's shorted out,, The converter still kept things fully powered. (But if I lost 120vac the inverter went LOW-DC in abourt 1 second).. Curently I have dropped them off line. I'll replace them soon.
turbojimmy
Explorer
Feb 09, 2014
My brother needed his battery back. I unplugged the MH from the house current and it still seemed strong. Tested almost full. So I don't think I hurt it with that old converter.

I popped in 2 new group 27 deep cycle batteries and plugged it back in.

In reading the documentation that came with the motorhome, there appears to be a battery isolator somewhere. I assume this is to allow the alternator to charge the house batteries but to keep the house batteries from draining the chassis battery. I've yet to find it, but I haven't traced all of the wires under the hood yet. There was a big, fat solenoid mounted to the alternator bracket that also does not appear to be factory. I'll sort it out once the new engine is in place.

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