GMC Motorhome: A freash Co-op/Koba motor lives and hey, lets talk about enging electrical systems…….. (Updated)

Boy, that was a mouthful of talking points, kinda big and important ones so I expect to have a page 2 today.  The guys are heads down ants on a cake and with some of my work finally becoming something to talk about…..yeah, I hope you can have some fun with this.

So around here when a coach pulls itself off the lift under it’s one new power it’s a big deal…Piles of work from many professional people go into our drive trains and to have it all come together well….that’s something to note.  

With another motor coming in within days, we need to get John and Julies blue baby breathing on it’s on.  Their 1973 really rare (original Bargman door latch) #214 off the assembly line got it’s drive train updated.  She drive in on her own, the best way…no trauma on the block or heads.  This makes the best motor for a rebuild. 

Their coach has occupied our lift (our labor bottleneck) for a bit but there was much to do   It was done the right way…EVERYTHING came out!    Once in there is now down here   The motor came apart and went through our machine shop and came back to us Drew Koba personally bringing it to the shop assembled  Where it was mounted on our run in stand and though a roller cam motor does not need the “run in time” to specifically break everything in still we need to know if she will live so yes, it ran on the ground….yes, the redneck lullaby..a big block running on the ground!    From there the magic begins to toss all that stuff back in the hole   and here is the new Co-op/Koba roller cam 455 WITH FitTech fuel injection…in the hole and pulling itself along    Focusing mainly on the drive train now the coach is in the big house for the balance of it’s punch list   Oh wait, betcha John would like to see the “Mr. Demile” closeup….. here . and my motor colr of grey industrial meat looks awesome…to me anyway.   Today we’ll be adding more stuff and putting the drive train through it’s first paces….what fun!    Oops, It’s 8am, I need to get out with the guys…I’ll be back for page 2 and a logical discussion on the engine electrical system in our coach and how far to go……..see THAT’s the big question! ……. I’ll write (updated) on the topic of today when that’s posted…..

See ya then….. 

So I wanted to bring you guys into a discovery process I’ve been struggling with while doing these 3 dash AC/heat projects.  I mean I am IN there with the beast!  And when you go into something that far, it’s always smart to step back…look at the progress and where you want to go.  I mean ANYTHING can be done with cubic dollars….or should it?  Truly the question is not what to do but how far do you backup and where to STOP!

Can you believe it, my computer went into update…….I’m back!

So the living area and engine electrical systems are very different…the engine electrical harness is from General Motors…the living area who knows…good thing we’re talking about the front harness.  It’s actually a pretty descent harness..… not the only cause there is always age and how bad the harness had been hacked up. 

Again, we could just rip the baby out with the bath water and put in a whole new harness or we can see what we can use.    The original harness doesn’t look so intimidating when it’s got all those “Klingons” on it!    You’ve seen that…….. The extra fuse blocks under the front hood or next to the old fuse block…..in line fuse holders scabbed in….I man if you wanna add all that new stuff you need to safely hook it up and boy folks idea of “safe and reliable” …..differ!  I’m not as much interested in ripping it all out as I am keeping the original integrity and adding to it.  That added stuff has to go though.    If I were to go the complete rewire with a unit like this….no one else in the GMC world would ever be able to diagnose problems plus you would have to extract and install every wire, fitting tie, connector, etc.  Yikes!

The “add to it” part that realy needs updating the the original ATC (glass fuse) fuse block to the newer and much better ATC style (European style) fuses.  

But see, I just don’t want to do THAT much work and modify THAT MUCH.  There’s nothing wrong with the wiring and harness…it’s the old bulb sockets (need cleaning and LED bulbs and something has to be done with that old fuse block.

The problem is  the original fuse block has wiring coming out it’s back to the under hood and a harness inside.  You can’t just go out and buy a new one….for sure not one with ATC fuses!  

So what to do?  We have Ruby, Texas Tux and Scott’s coach all have new dash wiring for their AC systems, all freshened up under front wiring and Mac’s MacDaddy connects color-to-color to the original harness.  What I wanna do is keep the harness clean….. add to it’s serviceability if I can, use only ATC style fuses but not tear out the world…..Easy-peezy!

So the first idea was to change all the circuits to 3 aftermarket ATC fuse blocks.  One for constant, one for ignition and one for ign off during start.  That stayed pretty clean and serviceable but I just felt it ended up looking like a high school science project    I mean it works……the original box is connected to the 3 aftermarket blocks via soldered wires to it….yellow constant…red ingnition and blue ignition off during start….hey it fits and works…….. but just a little science project looking!  Maybe I’m too picky but I wanted more. 

Having ATC fuses is one thing but what about working with the system, adding new wires and keeping things clean and safe.  So I went diver in on one of the aftermarket ATC factory style late model fuse blocks just to see how she works    Put in a little noggin time and a new Hekko solder station  this is a new fuse block wired to the original AGC style fuse block    Oh, and when you want to service the harness, check something…add something…can your fuse block do this?    2 screws and the entire fuse block is laying in the floor…….I mean GREAT access like putting that red wire from the dash AC blower there in….I knew I forgot 1!  …oh and one other nice feature we have maybe 11 circuits on the original the new system has 20…boy you can hook up musical horns, curb lights and more!. 

This is Ruby, tomorrow Texas Tux gets the outpatient surgery.  And then Scott brings up the end.  We already have another dash AC/heat projects scheduled to NOT replace the dash proper.  After these 3 I think I can do it…..lets see.

Each thing you think of subjecting your coach too it’s important to work your way through to your end goal and not get caught up in the weeds.  Filter #1 is….”If it fails will it leave me on the side of the road and have to be taken somewhere to get fixed?”  It may be cool to have some exotic system on your hot rod but it can for on a car trailer……your motorhome is too big to push and that tow bill will surly melt your wallet!!! Don’t put yourself in harms way.

So this exercise I think made the most use of what good we had, best use of labor and cost.  The concept can be duplicated from several sources so have at it.  If you would like to use the unit I did modified and ready to wire in call me.  The block set up is $200.  Lemme know if you want to givr’ it a try…I suggest you invest in a really good solder station and get good at tinning wire…the better the solder the better the connection……..  I use Hakko solder stations.   Yep, I haven’t seen a removable fuse block before…you may think it’s dumb…until you need to add a circuit the right way!

Do things once and do them right, but please…don’t do everything you read about……your motorhome will NEVER run again!

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