wamcneil

I’ve got the chassis-side combiner disconnected from my lithium house batteries. It would be nice to have some power from the chassis while underway, but in general I’m not looking for the alternator to charge the house batteries. As as long as I don’t depart at night with low batteries, the house should be able to run for 2+ days. And the generator is there as an alternative charging source. At some point I’ll probably reconfigure the combiner relay or add a dc/dc charger, but so far I haven’t been real motivated to try and connect the alternator to house batteries. Cheers Walter

Mine has the bmw lights, but I would assume they have similar mountings. Once I crawled up in there the attachments are pretty kludgy, but fairly intuitive. Mine just have some aluminum straps that go around the back of the light and hold it up in the aperture. I wish I had those van lights... I bet they are a much better fit for this application than the bmw housings. Cheers, Walter

After you fill it, watch it for several cycles. If the neck is cracked the level can go up/down a few times, sucking in air each cycle till the level eventually settles.

When the antifreeze heats up it expands, pressurizes the tank, pushes past the radiator cap and flows into the expansion tank. Then when the system cools down, it pulls the antifreeze back in. In mine, the difference between hot and cold is about 2-1/2 qt. If your level is not changing in the expansion tank it could mean there’s a leak where the pressure cap is soldered to the tube coming up out of the tank. This is a common failure point. If the tank is really low, it might explain yours not pulling in antifreeze when it cooled down, but if everything was sealed up it would likely expel some vapor when heating and then draw a significant amount of liquid back in as it cools. Cheers Walter

Also, consider having the sync cylinder rebuild while you’re in there. Mine started weeping shortly after I had all the rams done cheers Walter

Here’s my story https://www.irv2.com/forums/f115/need-advice-on-jacking-up-slide-out-431958-2.html Cheers Walter

diysolarforum has an active bunch of diy lithium builders. There are a small number of Chinese suppliers that folks report having experience with, mostly supplying prismatic sells for diy battery packs, and the feedback is kept updated on that site. I'd stick with a known supplier with references on that site and not experiment with new sources. Xuba is one with many reports of good service and supplying as agreed. It's kind of a wild west market with these gray market cells. Apparently the sellers latch on to a good supply of quality cells, but then have a hard time maintaining their supply over time. So whoever has the good cells right now is kind of a moving target. There are about 4-5 manufacturers of top quality lithium cells. Apparently the manufacturers occasionally dump a quantity of cells that didn't quite make the cut to be labeled 'grade A' and sold through retail channels. Somebody buys a large quantity of 2nd quality cells and then they go out through these sellers on alibaba. But there's not a steady and reliable stream of good cells, so it can be hit or miss. So, a certain brand of cells will be available for a while, then the sellers will shift to another brand. In my battery, cells were spec'd to be Lishen 274 ah cells, but the batteries arrived with ETC 277ah cells instead. Another quality brand is Eve with 280 ah cells.

I guess I should update... In general I'm really liking lithium batteries. But there have been some snags. As I dug into the batteries I found some serious problems with the construction. And after complaining to Xuba came to find they subcontracted construction to another company who was responsible for the shoddy assembly. Eventually came to the agreement that Xuba would find another contractor, carefully design a better-engineered 'product' version of the batteries and manufacture replacements. So that's where we are now. Xuba appears to be acting in good faith. The replacements should be done with assembly any day now and probably couple-months in shipping before I get them. Meanwhile, the batteries are working, but some of the connections inside have high resistance, and I'm having to work around limited current in and out of the batteries. Hopefully I'll be able to report wonderful customer service at Xuba and eventually getting the batteries of my dreams, but it's still in process at this point. Cheers, Walter

I wish you’d posted this about a month ago... before I bought a new hp mobile printer/scanner..,🤨 cheers Walter

The big 200a Dual Battery Isolator on the left feeds alternator current to both chassis and house batteries when the chassis side is charging (engine is running). This one is pretty straightforward. When you have elevated voltage coming from the alternator (middle terminal), you should see the voltage on the other two terminals. The smaller Lambert isolator on the right feeds charger/solar current to both house and chassis batteries when the house batteries are being charged. This one is not quite as straightforward as it looks... those diagrams posted above show the Chassis terminal on the right as being connected to that circuit breaker up above the big relay, but it's not actually like the drawing... On the top circuit breaker, the gray wire crimped to the 10ga red wire is a fusible link. From there, the red wire goes into the wire loom, crosses over to the other run box on the left side of the engine bay, through another relay in that box, back into the wire loom and back over to the battery isolator's right-side terminal. The big solenoid in the middle just combines the the chassis batteries (top terminal) with the house batteries (bottom terminal) only when you press the Battery Boost switch on the dash. Cheers, Walter.

That sounds like a plausible source of my problem. It seems to be vibration and maybe also heat related. Mostly shows up on the bumpy last 20mi of the trip home. I'll crawl under there and tighten the output speed sensor connections. Right, no warning lights. I've got a bluefire diagnostic adapter, but didn't have any fault codes. Their user interface is pretty clunky and crude, but it works...

Thanks. I'll double-check. Did yours also affect the cruise control?

Hi all, I've got an intermittent problem with the speedometer. I suspect it's related to the speed sensor, wherever that is... It usually starts happening several hours into a drive, and is made worse on a bumpy road. The speedo will drop by about half, then snap back up to speed, then sometimes shoot up 20% and immediately fall back to speed. This happens more or less randomly, but seems to be more frequent when the real axles hit a bump. When the cruise is engaged, it causes some jerkiness as the cruise control tries desperately to compensate for the wild speed changes. Since it affects the cruise control, I'm thinking it's not gauge related. I figure the gauge is reading speed off the data bus. Where does the system take speed information? I'm assuming there must be a sensor on the output shaft like a car would have? Do these sensors fail, or is this more likely connections/wiring? Thanks all, Walter

Sure. Send me PM with your address.

Ok, got it out of the AC. Mine is 2003 dometic 630515.321 Part number on the solenoid is not legible, but looks just like this one: http://www.nwrvsupply.com/product/3310714005.html IMG_4330.HEIC

I’ve got an AC for parts. Let me know if you need the solenoid. I suspect the reversing valve was this unit’s problem, but I believe the solenoid is good. Cheers Walter

I use a small battery disconnect switch (rated for 48v) on the positive solar feed wire. No harm in using a circuit breaker, but the solar panel cables don’t need overcurrent protection. Cheers Walter

Nice setup! Thanks for sharing that Michael

Could this instant hot issue is revealing a separate problem with the 50a service coming to the coach? I’m not an electrician either... but I believe there should be one point in the 50a distribution panel where the neutral bus, grounding conductors and ground rod are all connected together. But maybe the chassis is disconnected from ground while transfer switch is on external 50a service? Cheers Walter

No huge loads like AC. It’s mostly to run the microwave or induction cooktop and warm up leftovers without feeling like I need to fire up the generator every day. Recharge mostly with solar (1100w). It’s looking like I may have an extra 270ah lithium battery to use for the house loads. I haven’t tried to calculate the house loads separate from the inverter, but that’s the big power consumer (fridge mostly, coffee maker, computer, tv). Other house loads are just led lights, water pump and in winter the aqua hot would probably be the biggest consumer. Cheers Walter

Hi all, I've got what might be a crazy idea. The problem: My batteries are waaaaaay at the back of the coach right-rear. But my inverter is up forward on the left. 4/0 cables between, but still a lot of voltage drop at high current. No easy way to fix this, unfortunately... Moving the inverter closer to the batteries has entered my mind, but then I'd need to re-route a lot of wiring.😞 What if I replaced the inverter with a 24v inverter? Dropping the current in half should get my voltage drop down to the 3% range. Other than the obvious voltage change, a 24v Magnum inverter/charger would be plug-n-play swap for the existing MS2012. Solar controller can run 12v or 24v, so that would only be a dip switch setting. It would be pretty simple to separate the 4/0 cable run from the high-current run-bay and repurpose it for 24v, then wire the existing house batteries in series for 24v Magnum AGS is good with 12v or 24v I've got enough room on top of the batteries to install another 12v battery for the house loads and run cables back to the high-current run bay to feed everything except the inverter. Add small 12v charger or 24v/12v converter for new house battery Anything I'm missing that might make this plan end in sadness? I remember needing to connect the neg inverter cable to the chassis and the neg battery cable. I suppose I'll need to connect the new 12v battery neg to the chassis when I disconnect the inverter from the chassis. Thanks, Walter

That's a good idea. I think I'll look into LED in my driving lights.

Here’s my experience installing led bulbs in my BMW housings. https://www.irv2.com/forums/f115/diy-2003-monaco-dynasty-led-headlight-upgrade-379517.html Mine are the older variant without the angel eye rings. So might be a little different than yours. It took some fiddling, but the end result is a huge improvement. cheers Walter

From a code perspective, is there any reason why the 50a receptacle needs the be wired with a 50a breaker? If you've got a 50a breaker, you need 50a wire. Bit I'm not sure it would be a code violation to wire the 50a receptacle with a 30a breaker and 10 ga wire. Nothing unsafe about that. But as you noted, just need to be aware that you can't run more than 30a worth of loads on each leg of power. That would be a lot like plugging 4 hair dryers into a bathroom 15a circuit. Nothing wrong with that as long as you know you can't turn on more than one hair dryer at any given time. Cheers, Walter

No, there is not because it would not be code compliant. The motorhome has two hot conductors, one neutral conductor and one ground wire. Your adapter has two hot conductors and a ground wire. So you’re sending neutral current down the ground wire in your adapter and then through the ground wires in your house. These days, the ground wire isn’t allowed to carry load currents. Using the ground wire for current is potentially unsafe. Cheers Walter