Measuring Current on DC Circuits

On most RVs, there isn’t a nice wiring diagram with fusing, grounding and splice locations, wire colors, and printed circuit identifiers like we expect on a car.  When something isn’t working, it’s often not obvious what circuit it’s on; when a fuse blows, we often don’t know what’s on the circuit that might have caused it.

It’s also pretty common for fuses to be oversized, not so much for the wiring, but such that if a problem were to occur, a fuse isn’t going to be very quick to blow.  It’s not easy to work with a standard multimeter to connect inline, and measure the current with the load turned on.

Here’s what I use:

EXTECH Automotive 30A Current Tester


This is one of my favorite automotive electrical diagnostic tools beyond a multimeter.  It’s a really simple current meter that plugs in where the fuse goes, and the fuse plugs in to the side of the connector.  I can see that my water pump peaks at just under 5A, and the furnace at 10A.  Same thing for lighting circuits, the refrigerator, etc.  This also allows you to put together an estimate of what you need in terms of batteries, solar, generator runtime, etc. if you were to run something for a particular amount of time.

It’s not quite as sophisticated as the Kill-A-Watt meters used for 110V power, but does it’s job quite well.

The Grey Ghost’s New Kitchen, Part 6: Loose Ends

This has dragged on quite a while, and will probably continue to, but I thought it might make sense to post some comments on a number of smaller items so far in the project.  Some are just notes on how I’ve done certain things, others are thoughts on what I’m planning.  As always, comments and suggestions are appreciated!


I’ve been asked how I have finished the cabinets–both what I’ve used and how it was applied.  All of the wood used is a red oak–in the case of the wood used for the face frames and the plywood for the sides of the cabinets, it was purchased at Lowe’s.  The cabinet doors and drawer fronts are also red oak, but supplied by Barker Door in Oregon.

I used an orbital sander (like this) to progressively sand all surfaces, starting with 120 grit, then 220 grit.  Before a final pass with 320 grit, everything was wiped with a wet rag to raise the grain–this results in a smoother finish when stain is applied.

The stain used for these cabinets is Minwax’s Espresso.  I found it on the shelves at Home Depot, but it can also be found online for about the same price.  I tried their PolyShades all-in-one product, but wasn’t nearly as satisfied as with the separate stain and polyurethane.  The stain was applied with a foam brush, and after sitting for about five minutes wiped with a paper towel.  The stain doesn’t dry quickly–it needs a day or so before it’s ready for polyurethane.  This caused a little bit of trouble at one point trying to get staining done when the weather wasn’t cooperating.

The polyurethane goes on pretty easily, but you do have to be careful to make sure you don’t go too thick and get runs.  A couple of hours between coats is all that’s needed for this to dry.  To get a smooth finish, a very light rub with 000 steel wool between coats knocks down any bubbles/bumps.  For most parts of the project, I put on 3 coats of polyurethane.

Stove cover

This is one part of the project that took a lot more effort than I expected.  I wanted

Routing on underside of cover.

the stove cover to sit level with the countertop, and to fit over the grating so that it wasn’t inclined to slide around while driving.  That meant a lot of work routing out about 1″ across most of the underside of the cover.  This probably took several hours, but I’m happy with the result:

Cooktop cover in place.

Ceiling trim

Haven’t quite figured out what I’m doing here.  I left myself enough room at the top of the cabinets to do a small soffit (mainly to cover some of the holes from the old cabinets), which I plan to add lighting to.  Just haven’t done it, and haven’t decided what I want it to look like.

I also need to figure out how to clean the ceiling.  It has a fine layer of what I think is diesel soot, and is a royal pain to get free.  I’ve gotten a few sections clean with a lot of work, which ends up making it worse by highlighting how dirty the rest of it is!


Looking forward into bathroom from bedroom, as it was when I bought it.

The floors were actually the first project, tied in with replacing the shower stall.  I used Allure Aspen Oak click-lock vinyl plank flooring, bought at Home Depot.  It’s more expensive than the laminate planks, but being solid vinyl is way more tolerant of moisture.  I’d had problems in the bathroom with the pressboard swelling from drips from the shower door and wet feet.

I didn’t take any pictures during the process, but here are a couple of pictures before and after in the bathroom.

Vinyl floors in bathroom and bedroom.

These floors have held up really well, and I think they do a good job lightening things up and providing contrast with the darker cabinets.

That’s all for now, but hopefully the next few posts won’t take so long!



Belts, Tensioners, and Pulleys

Years ago, during a pre-purchase inspection before finalizing the deal to buy the Grey Ghost, the Volvo mechanic pointed out that both belt tensioners really needed to be replaced, but that it wasn’t urgent.  I put the project off for a while–amost a year–until after successfully starting the world’s first nuclear reactor using heat pipes and Stirling engines.  After doing that, replacing a pulley seemed like it should be pretty easy.

It was almost too easy.  Just a few minutes, in fact, working at eye level and without getting dirty.  Loosened the spring tension with a 1/2″ drive ratchet, slipped the belt off, and unscrewed one bolt with a 14mm socket and the pulley was free.  I knew the other tensioner needed to be replaced, but the Cummins dealer didn’t have one on the shelf, and I was only in town (Las Vegas) for the weekend.  There was also a little sticker shock–they wanted almost $300 for that little thing.  I figured the worst that could happen was the tensioner letting the belt slip, in which case I could cut the belt and forgo AC until I got somewhere to fix it–maybe uncomfortable, but not disabling.

Somewhere along the way, I did a little searching and came across a Gates cross reference for the Cummins part number.  There was a pretty big difference in price–that tensioner would only be $120.  So it got replaced in 2014.

Both tensioners have done their jobs just fine, but recently I started noticing a bearing squeal when it was wet outside.  Knowing the tensioners (and tensioner pulleys) were basically new, that really only left the idler pulleys, one for each belt.

With some really nice weather over the weekend, I decided it was time to take care of it.  Of course, I decided this after the Cummins dealer was closed, and unlike with the tensioners, I couldn’t make out a part number on the idlers.  A little searching turned up a number that crossed to a Gates part, one that wasn’t in stock at the NAPA distribution center that would normally be the go-to place.  On a whim, I called the closes O’Reilly’s–they had the part, for about $35.  I headed down there, and while they had the part I asked for, it wasn’t the one I needed.

The clerk tried to be helpful (I was playing this RockAuto commercial in my head…), asking what it went on.  When I said a Volvo truck, he started typing and I was shocked to see the VNL listed as a model just after the V70 and ahead of the XC90.  Really?  Ok, but I have a Cummins engine–sure enough, it was listed.  Along with all of the part numbers I needed for the idlers, tensioners, and belts.  And all of them were in stock locally.

I did shop around just a little–I wanted the idler for the fan belt right away, since it was already off–and found that I could do better on Amazon by a pretty good margin.  I picked up the idler for $90, and ordered the other idler and both belts.  Combined, I was able to save $75.

This is one of those projects that takes longer to write up than to actually do.  Start to finish was well less than an hour, and most of that was just fishing the fan belt between each of the fan blades and the fan shroud.

Tools needed:

  • 14 and 15mm sockets
  • 1/2″-drive ratchet with long handle or cheater bar
  • Pry bar or breaker bar

Parts needed (pictures linked):

  • Gates 38610 AC belt tensioner, $119.78
  • Cummins 3978022, $141.14, or Gates 38504 fan belt tensioner, $85.78
  • Gates K120842 or K120842HD Fan belt, $68.16
  • Gates K060637 or K060637HD AC belt, $18.79
  • Gates 36286 fan belt idler pulley, $67.85
  • Gates 36223 AC belt idler pulley, $39.45

I mentioned that I had replaced each of the tensioners separately, but given that most of the big trucks put into RV service already have quite a few miles, I’d probably recommend doing everything at once (the extra cost is in parts, not time).

The first thing to do is get the fan belt loose.  Stick the 1/2″-drive ratchet into the square hole on the tensioner and push up (clockwise) to relieve tension.  Slip the belt off of the idler pulley above the tensioner, and release the ratchet slowly.  You may need a pry bar to support the tensioner in place while you reposition the ratchet to fully release the tension.

Ratchet on fan belt tensioner, squeaky idler on top side of belt.

Do the same thing on the AC belt tensioner, except using a 15mm socket and prying counter-clockwise.  Again, slipping the belt free at the idler pulley is easiest.

Ratchet on AC belt tensioner. Idler to be replaced is just above ratchet head.

The AC belt is easily freed with the fan belt pulled off of the water pump, while the fan belt will have to be fished over the fan blades into the space between the fan and radiator in order to get free.

The pulleys are both held in with 14mm bolts–unscrew, swap out the pulleys, and re-tighten.  Install the new AC belt first, then fish the new fan belt into the space between fan and radiator, and over each fan blade before slipping it into place.  Same operation in reverse with both tensioners, though it may require a little more effort going back together–you’ll have a stiffer, newer belt, and stronger tensioners.

Done. New belts, tensioners, and idler pulleys.

A few things were learned here:

  • Like with cars, the dealer isn’t necessarily the cheapest place for parts.
  • Unlike with cars, most auto parts places can’t look up your truck’s make and model (though neither can the dealer…they tend to want to work from your VIN or ESN).  O’Reilly’s proved an exception here.
  • Despite being bigger, the ease of access and eye-level work area made it much easier than working on a typical passenger car.
  • At about 240,000 miles, both idler pulleys were well worn, but both belts were probably fine to leave in service.  Not too different from passenger cars in that regard.

Going to the dentist? Where’s the compressor?

I stumbled across the idea of using a dental air compressor while looking at pictures of a garage build, and finally pulled the trigger on one this past week (after going to the dentist, and confirming that there really was an air compressor in one of the cabinets in the office).  It turns out they aren’t as expensive as you might think: cost delivered was $180 on Amazon for a 1-hp, 1.6-gallon model that will fit into the storage bay vacated by the old lead acid batteries.

Of course, when it showed up, I pulled it out of the box and turned it on.  Eventually, I found a package with the instructions, and a muffler and short piece of tubing, which made it a lot quieter.  I still haven’t read the instructions…keeps life interesting!

Here’s a video put out by the manufacturer:

And here’s my video showing just how much of a difference the muffler makes:

It’s not silent, but sitting in the kitchen of the RV the noise is comparable to the rooftop air conditioner.  Far, far, quieter than anything you can pick up at the local home improvement stores.  While it doesn’t always happen, Amazon had just about the cheapest price I could find, and with Prime, it was here in a couple of days.

It’s already been used for a number of routine (for me anyway) tasks, from airing up tires to running an impact wrench and air ratchet.

Microwave, Convection Oven, and Range Hood

The microwave and separate hood were one of the things I was looking forward to changing as part of the kitchen remodel.  The hood’s fan made plenty of noise, but moved very little air.  And the microwave was higher up than was comfortable.

Kitchen before remodeling started

I also wanted to be able to use an oven for longer periods of time without dealing with propane exhaust.  The convection oven was part of the solution to that (though since it runs on the inverter, the lithium battery upgrade was also part of the process).  Ideally, I would have liked a narrower 24″-wide microwave/hood combination, but 30″ is the standard.  In part, that’s what made the project a total re-do, as opposed to piecewise upgrades.

Whirlpool Gold WMH76719CS Over-the-Range Microwave Oven with Convection and Vent Hood

The microwave I picked out was a Whirlpool Gold WMH76719CS Amazon $579.99, AJ Madison $489.10 as of today).  At the time I bought it, there was a rebate that basically made it the cheapest stainless over-the-range convection oven I could buy.   With nearly 300 reviews averaging 4.4/5 stars, you could say I was expecting a pretty good appliance–and it is–but it’s not without a few shortcomings.

First of all, it really does do everything it should–microwaving (with all of the sensor cooking stuff), convection cooking, the hood moves a fair bit of air with a reasonably acceptable amount of noise, and it’s a pretty big cavity.  For a shorter user, especially since I mounted it a bit higher than what’s standard, having all of the controls and display across the bottom is nice.

I do have a few gripes though:

  • The “beep” when you press a button isn’t quite in sync with button presses being registered.  Here’s what I mean–there’s an “add 30 seconds” button that I can quickly press 3 times, hear 3 beeps, but only have 2 of 3 recorded for a minute on the clock.  The part of the control board doing the beeping should send a carrier pigeon to the other part of the control board that’s controlling the microwave.
  • The button for the oven light is well inside the bottom corner, and above the button for the fan.  It’s impossible to find in the dark.  It should have been on the bottom row, and near an edge/corner of the control panel, not 4″ in.  Either that, or make it light up just a bit.
  • While the control panel on the bottom is nice, it makes for a big door.  I find myself frequently stepping back as I open the door, and with the opposing slide-out closed, I often end up ducking under the door when moving something from the counter into the microwave.  This is the one thing that, if I did it again, might cause me to pick a different model.
  • The owner’s manual is absolutely worthless.  I’m used to appliances like this containing a breakdown of all of the menus and what’s actually going on with a particular setting.  What’s the difference between convection bake and convection roast? Well, I know that convection roast draws more power, but that’s about it.  The owner’s manual is silent on this and every other cooking option.  It’s basically just a couple of sheets full of warnings that would apply to just about any microwave.

Again, overall I’m pretty happy.  The inside has been easy to keep clean, and it looks sharp.  It doesn’t really have to be any more expensive to address my complaints–it’s just a little rough around the edges with the user interface.


Cooking with Gas!

Ok, so I could cook with gas before.  But now it’s a much more pleasant experience.  The original RV oven went to a new home, along with the oven’s pilot light, too-small broiler compartment, and manual ignition stove top.

I wanted to replace it with a fairly inexpensive, but good looking gas range.  I wanted a waist-high broiler, so that anything I could fit in the oven could be broiled.  I wanted electronic ignition, so there were no pilot lights to mess with.  I wanted sealed burners to make cleaning easy.  And since it would be free-standing, I wanted a storage drawer to make up for some of what I’d be losing in terms of storage. Oh, and since I have LP, not natural gas on board, it would need to be able to run on LP.

Then we came to the question of 20″ or 24″ width.  Some of that ended up dictated by clearances and the space available.  Between the water heater and refrigerator cabinet, there was just enough room to squeeze in the dishwasher, range, and spice rack if a 20″ range was used.  A 24″ range would mean giving up the pull-out spice rack, and while there were more 24″ models to choose from, they were much more expensive (albeit from more well-known brands).

Avanti GR2013CSS 20″ Gas Range

What I ended up with was an Avanti GR2013CSS 20″ range, in stainless with a black glass door with window.  The link above is to Amazon, but at the time AJ Madison had a better price (more on that later).  It’s narrower than the range that came out, but also fills the full cabinet depth.  The oven cavity is a lot more usable–a 9×13″ pan fits with room to spare, with the long dimension running front to back.

It was easy enough to swap out the orifices on each burner (6 of them including the two in the oven), and installation was straightforward.  I did have to space it out from the wall just a little though, in order to clear the drain line running from the kitchen sink.  Overall, it’s a much better feel in terms of quality than the old range, particularly when it comes to the oven door.  It’s a properly sprung and sealed glass door, like what you’d expect at home.

I do wish the burners had a little wider range–there are three burner sizes (1 large, 2 medium, and 1 small), but I often find myself moving a pan from the large burner to the small one when going from a boil to simmer.

I definitely like not having to mess with the pilot light, and both the stove top and oven are much more usable.  One thing I did though, to make the covered workspace more functional, was to raise the countertop height just a bit from the standard 36″, so that the rim around the grating was at the same height as the bottom of the countertop, and the cover was routed out to surround the grating.  The weight from the cover keeps the grating from rattling, and the grating keeps the cover from sliding around.

Interior of oven, with light on.

I don’t often use it, but it is kind of nice having a light in the oven.  I suppose I’ve grown accustomed to opening the door to take a look after years without a window.  It’s an incandescent bulb, but assuming it won’t be on for long periods of time that shouldn’t be a big deal for energy management.  Notice that there are two racks in the oven as well, and both are usable with casserole dishes or cookie sheets.

I paid $488 delivered last January from AJMadison. Amazon shows it at $642 as I write this–so quite the savings from AJMadison, though it did take a little while to get them delivered (part of that due to a couple of winter storms).

After a year using it, I’m still pretty happy.  One of the igniters has been a little flaky once or twice, but other than that it’s as good as new.  Bouncing down the road, nothing has picked up wear marks, and the drawer hasn’t opened at all in travel.

Next up is the over-the-range microwave/convection oven.