So what did you do to your GMC today?

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I'm in the middle of a rear wheel well project that includes resealing inner fenders, suspension pressure gauge relocation, Hi Tee modification, and Dual vapor Separator mod. While inspecting the TBI vacuum hose I noticed a cracked TBI base gasket failure. Guess what my next project is going to be?PXL_20250626_024318615.MP.webp
 
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Carl do you have a carb or FI?
If a carb is does your distributor vacuum use ported or manifold? Ported will get better emissions.
Carb, ported. I looked this evening (after the outside temp went below 100) and couldn't find anything obvious. Maybe my carb gasket split too, like Louis'. The vacuum is pretty steady at about 13 inches at a low idle. A little lower than normal, but I DID adjust the idle speed down a bit.

Funny thing, the coach is running as good as ever.
 
interesting. I noticed my idle was a little high on the last trip, I wonder if that could be it
I'm in the middle of a rear wheel well project that includes resealing inner fenders, suspension pressure gauge relocation, Hi Tee modification, and Dual vapor Separator mod. While inspecting the TBI vacuum hose I noticed a cracked TBI base gasket failure. Guess what my next project is going to be?View attachment 15506
 
interesting. I noticed my idle was a little high on the last trip, I wonder if that could be it
Try using a can of carb or break clean to find the leek. Spray around and when you hit a spot that cause the idle to increase you have found your leak. Just Rember that stuff is very flammable.
 
I think I just have the idle set too low. My logic was that if the idle was really low, so would be the emissions, but I guess that thinking is faulty. I'll re-ste the idle, and make some small adjustments to the idle mixture screws and then have my mechanic check the emissions before I take it back in.

It actually IS about 400 miles from due for an oil change, but I was planning on waiting until after next month's trip to Silver City (almost exactly 400 miles). And, yes, it probably could benefit from a new cap, rotor, and plugs, but there's no indication that any of those are problematic.
 
I took mine in for emissions. It failed. Low on Co and high on HC. I guess I'm going to need to look for a vacuum leak.
I took mine in for emissions. It failed. Low on Co and high on HC. I guess I'm going to need to look for a vacuum leak.
Most of our Temperature control vacuum systems have leaks. I disconnect that line from the manifold and plug that port for the test. Helped my Hydrocarbons quite a bit. Also, set the idle as high as allowed by the test (it is 1000rpm in CA, check what it is for AZ). Idle HC is always a struggle for me to pass on the Stretch and those things seem to help me. Good Luck!

John Shutzbaugh
 
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Tested my 15K BTU roof-top heat-pump using a 4KW inverter and 280Ah (3584Wh) battery. It starts and runs! In "Turbo" mode (fan and compressor both at "high") I should get around 3.5 hours running non-stop. Hopefully, the compressor will cycle and I will also use a lower setting to increase my duration.

The inverter was drawing a little over 950W from the battery in Turbo (around 260W at lower settings and only 65W with just the fan). With 900W of solar on the roof, at the hottest part of the day most of the power requirements can be met from the panels; increasing the time the system can run. Plus, I will have a second battery on Monday, doubling everything.

I will completely test the system in the real world the weekend of the 11th.
 
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I took mine in for emissions. It failed. Low on Co and high on HC. I guess I'm going to need to look for a vacuum leak.

I think I just have the idle set too low. My logic was that if the idle was really low, so would be the emissions, but I guess that thinking is faulty. I'll re-ste the idle, and make some small adjustments to the idle mixture screws and then have my mechanic check the emissions before I take it back in.

It actually IS about 400 miles from due for an oil change, but I was planning on waiting until after next month's trip to Silver City (almost exactly 400 miles). And, yes, it probably could benefit from a new cap, rotor, and plugs, but there's no indication that any of those are problematic.
Usually there is an allowable maximum for that. Should be easy to find out what it is. Usually a higher idle will help in my experience. Better yet is someone with a measuring tool. HC and CO are pretty easy measurements to get without much outlay. The 4 gas is more and I suppose there's at least a 5 gas nowadays.
 
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Finalized my solar entry wiring (no more wires passing through at the top of the entry door):
Replaced the vent cap over the kitchen plumbing vent. Pushed through the sealing caulk around the PVC pipe and dropped two 10ga "solar" wires through. Protected the wires by installing a flexible plastic grommet over the aluminum cutout edge. Drilled two 1/4" holes in the side of the vent cap for those wires.​

Cut holes in the floor for two pedestals for a 5ft dining table between the dual jackknife sofas.

Ran the AC from batteries from 11AM to 6PM (when the coach went back into storage).
Batteries started at 60% (disconnected since the last test) and finished at 30%. I realized approx. 750W from a theoretical maximum of 900W of panels, plus added my ground deployed panels (theoretical 600W max; probably 350W in reality) to assist. At current usage I could have potentially achieved another 5-6 hours of operation before depleting the batteries completely (probably less as the solar offset would decease in the evening), but the air outside was cooling off and becoming pleasant anyway.​
 
Ashamed to share. I installed gas strut supports on my generator door today. Worked great a couple of times. Then one side broke. RATS!
 

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Ashamed to share. I installed gas strut supports on my generator door today. Worked great a couple of times. Then one side broke. RATS!
Reinforce rib with a strip of steel or aluminum. Rivit in and secure to that. Never be ashamed. We all learn from our mistakes. I like the idea. I hate holding it up with a stick or sticking the cable into the rear window weather stiping. What shocks and brakets did you use?
 
Reinforce rib with a strip of steel or aluminum. Rivit in and secure to that. Never be ashamed. We all learn from our mistakes. I like the idea. I hate holding it up with a stick or sticking the cable into the rear window weather stiping. What shocks and brakets did you use?
I used shocks and mounts from Applied GMC.
I also plan on reinforcing the rib just as you suggested.
If this is the worst damage I do to the rig, then I guess I'm doing okay.
 
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I took mine in for emissions (again). This actually started yesterday when I had it in to the garage for some carb adjustment. Jim, the mechanic, said it was VERY touchy, and by the time I got to the testing facility, it had changed and it failed again.

Back down there this morning and through a bunch of adjusting etc, Jim got the idle air fuel adjustments where they needed to be, but every time he would rev it a little, it would change when it came back down to idle. When he hooked a tach up to it and found that it was running about 100 RPMs higher than it was before the rev. He added an additional spring to the throttle and it stabilized the idle and the emissions.

Meanwhile, during all the starting and stopping sequences, the key cylinder decided to freeze up, so the engine could not be shut down. Good place for that to happen, it had been kind of wonky for some time. Jim ordered a new key cylinder and I went back down to emissions. It passed this time, no problem.

Back to the garage where Jim replaced the ignition cylinder and it worked better than I can remember it ever worked. I'm happy it happened there rather than at a gas stop or out on the road somewhere.

Always an adventure!
 
I took mine in for emissions (again). This actually started yesterday when I had it in to the garage for some carb adjustment. Jim, the mechanic, said it was VERY touchy, and by the time I got to the testing facility, it had changed and it failed again.

Back down there this morning and through a bunch of adjusting etc, Jim got the idle air fuel adjustments where they needed to be, but every time he would rev it a little, it would change when it came back down to idle. When he hooked a tach up to it and found that it was running about 100 RPMs higher than it was before the rev. He added an additional spring to the throttle and it stabilized the idle and the emissions.

Meanwhile, during all the starting and stopping sequences, the key cylinder decided to freeze up, so the engine could not be shut down. Good place for that to happen, it had been kind of wonky for some time. Jim ordered a new key cylinder and I went back down to emissions. It passed this time, no problem.

Back to the garage where Jim replaced the ignition cylinder and it worked better than I can remember it ever worked. I'm happy it happened there rather than at a gas stop or out on the road somewhere.

Always an adventure!
So glad it worked out well for you.
 
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