So what did you do to your GMC today?

  • Please note, the forum recently had a problem with outbound emails for notifications, registrations, etc. A new email provider has been set up which should resolve all email issues. If you have any further trouble, please DM Christo or reach out via the Contact Us link in the website footer.
Tybalt39 said:
Question...

How is the 50A DC-DC treating your alternator/starter battery (I'm assuming you have a 100A alternator)? Is the alternator struggling at all, or overheating? I've been concerned about installing my 40A DC-DC w/MPPT for that reason (I currently use MPPT function for ground-deployed panels in addition to my primary MPPT and rooftop panels). Did you connect to the battery or directly to the alternator? I've read connecting to the battery is recommended. Just gathering data.... :)
Click to expand...
It’s been kind to the starter battery. I thought it was draining it at first but after watching it a few times, it stops pulling fairly quickly after shutting down the motor. As far as wear on the alternator, I’m not gauged for that but haven’t seen anything that would concern me. BUT now you’ve got me thinking about more gauges, lol

My feed wire is 4AWG from the positive battery post on the firewall all the way to the electrical cabinet.
 
  • Like
Reactions: Tybalt39
I'm jealous of all you guys neat projects. I'm trying to get my newly acquired 78 up to snuff. It's been setting still for almost a decade.

I replaced 15 feet of vacuum line in the engine compartment. Had to stop to order more. Looks like I've got another 20 feet or so to go.
 
  • Like
Reactions: Carl Stouffer
Went to fill up with gas and had gas leak out of the liquid separator in drivers side wheel well, also the vapor canister under the passenger seat. Liked Keith's V. idea on using a check valve.

IMG_0004.webp
IMG_0005.webp
 
tmsnyder said:
What canister is that?
Click to expand...
Keith V came up with the idea of making his own using a Jeep check valve

Keith V

Thread 'A new evap check valve'

Ive been through 3 of these stupid check valve for the charcoal canister.
So Im trying to find an upgrade.
I found a valve that fits into the top of the fuel tank for a newer jeep
check_.webp


Im not willing to cut a huge hole in my tank, so I made this.
It should be a direct replacement. I got it assembled today and leak tested it.
Now I just need to mount it.
Credit to Adam for the copper pipe idea
Don't look at the solder job!

20250706_184830.webp
  • Like
 
LarryW said:
I found 2" ABS in 2' piece. Top and bottom caps, and glue?
Click to expand...
I found those also on Amazon. At the time I was at Home Depot and PVC is what they had. When you live 40 miles away from any town with supplies you just can't run to the nearest hardware store. Home Depot lists the item, but it is not a stocked item at the Cheyenne store. It has to be ordered and shipped in. The hassle of living in remote areas. But the peace and quiet is well worth it.
I had lived in Colorado 60 years along the front range and watch it grow to the present-day congestion, and you just shake your head as to why when you get away from all the hustle and bustle.
 
  • Like
Reactions: tmsnyder
OhioMotorhome said:
I'm jealous of all you guys neat projects. I'm trying to get my newly acquired 78 up to snuff. It's been setting still for almost a decade.

I replaced 15 feet of vacuum line in the engine compartment. Had to stop to order more. Looks like I've got another 20 feet or so to go.
Click to expand...
sailor man said:
Took the first check out drive yesterday with Jacob.
Nice cold air was blowing well out of all the vents, even when the engine was shut off. It was a pleasure not to need the engine running for the air conditioning compressor to operate, the blower push air well or the condensing coil fan to run.
Click to expand...
IMG_2994.webp


The cockpit is coming together.
Screens galore!
IMG_2989.webp


The little screen in the center is for the Assistive Driver's System.
The two white LED lights are blind side warning lights.
I got in the coach before dawn this morning to check if the lights were all working. All were except for the low beam LED headlights on the passenger side. Got ti=o fix that.
The iPad can answer and send calls. So can the radio. The iPad will be the GPS using Maps.
The nicest thing is that the dash air-conditioning started blowing quite hard and cold and I had not started the engine yet. What a pleasure.
Air was coming out all of the vents. Nice.
The right sun shade monitor is not yet operational and it is for a forward view from the passenger's seat.
It appears that the steering wheel is a bit to the left, but it works for me. I only have a functional left eye and the wheel is pretty much aligned with my only seeing left eye. It prevents parallax error causing a drift to the right.
It took a long time to get to this point.
 
With all the talk about testing for leaks, I went out to my GMC tonight to look for any leaks. We have had two days of lots of rain, so it was a good time to look.

I discovered the vent in the bathroom was leaking. I imagine it will just be a matter of disassembling the round vent fan, and then resealing it. Not too worried about that.

However, I also found some minor leaks around the windows in the rear lounge. I have kept those windows shut, and have not opened them. Tonight I discovered that they were both cracked open, and thus allowing in some rain. I'm guessing that the vibrations of driving allowed them to creep open. They have latches, but they appear to be useless in keeping them firmly shut.

Have any of you experienced the same thing? If so, have you come up with a fix/solution to keeping those windows tightly shut?

Thanks.
 
  • Like
Reactions: Larry Pontiac
RvRev2 said:
With all the talk about testing for leaks, I went out to my GMC tonight to look for any leaks. We have had two days of lots of rain, so it was a good time to look.

I discovered the vent in the bathroom was leaking. I imagine it will just be a matter of disassembling the round vent fan, and then resealing it. Not too worried about that.

However, I also found some minor leaks around the windows in the rear lounge. I have kept those windows shut, and have not opened them. Tonight I discovered that they were both cracked open, and thus allowing in some rain. I'm guessing that the vibrations of driving allowed them to creep open. They have latches, but they appear to be useless in keeping them firmly shut.

Have any of you experienced the same thing? If so, have you come up with a fix/solution to keeping those windows tightly shut?

Thanks.
Click to expand...
If you're talking about the OEM windows, yes, I've experienced them opening up. Do you have the OEM latches?
 
RvRev2 said:
Yup, OEM! They don't seem to work so well.
Click to expand...
See if you can push and open the moving sash from the outside while it's latched - many times you can as it's not a proper locking mechanism.

The OEM latches have the bent spring steel strip that has a hook on the top, and when pushed down that hook catches the bracket on the fixed sash, mechanically locking them together. Many times that spring steel strip has been lost/damaged and the replacement doesn't have the hook, so it doesn't lock the window.
 
I took mine down to my mechanic friend and had him replace my lenzi brake booster. The one I got from Dave and installed myself, last Summer had suddenly failed for some as yet unknown reason. Dave sent me a new one at no charge. I decided to have My mechanic friend do it this time because it was a half day job for him and it would have been a multi day ordeal for me, due to mostly not having the proper tools.

When I got the coach home (with MUCH better brakes) I put it on the lift, drained the oil, and changed the oil filter. I will grease it and re-fill the oil tomorrow.

Getting ready for another six week cross country trip in about three weeks.
 
Last edited:
GMCMI Spring 2026 Rally
Applied GMC

Share this page

Share this page
Top Bottom
Back