Newbie - 78 GMC Sierra Classic 25 Camper Special

[BuckB78GMC]

Howdy guys, I'm new to the forum and the proud new owner of a 1978 GMC Sierra Classic 25 Camper Special 2WD. It has the 454, TH400, Corporate 14 bolt. It has a few dents and the original Burgundy or Maroon paint is a bit faded. The interior is in pretty darn good shape for a 32 year old truck that was I bought from a farm in the hills above Snohomish, Washington. It has a tilt steering wheel, AC (that still works), full gauge package and I believe as part of the Camper Special thing a HEAVY duty tow hitch, dual saddlebag style fuel tanks. 20 gallons each, I think, big radiator, auxiliary tranny cooler and it was wired for a bumper pull trailor, fifth wheel trailor and slide in camper. I do have a few of the known issues with this type of truck, though. The doors have to be slammed hard and lifted to close and even when closed they rattle when going over bumps. Are there adjustments I can do or pieces that can be tightened? I need to pull the passenger side door panel off and knock out a dent, anyway. The fuel gauge looks to be reading correctly for both tanks when I flip the switch on the dash but, I found out the hard way that my tank selector valve was not switching my tanks. So, I need to get that troubleshot down to a switch, selector valve or wiring issue. I now have it just feeding off the driver's side tank which is all fine and good because the previous owner couldn't find the key to the passenger side locking gas cap...so, I will be removing that the hard way unless one you knows an easy way to get them off. I was thinking a drill or BFH but, both of which could cause a spark and ruin my whole day....lol. Also, as stupid as I sound. How do I get the rear brake drums off of that full floater Corp. 14? I'm guessing take the bolts out of the flanges and pull the axles first. The secondaries aren't opening on the Q-Jet 4bbl carb which from the numbers I looked up appears to be the original put on in 78. However, the Motor is painted and still shiney Goodwrench crate motor black. There is also no engine ID number on the little plate in front of the passenger side head. Both of these lead me to believe I have a replacement engine which I have no clue what the specs are. It has a fare bit of lope to it at idle but not much in the way of neck snapping torque or HP that I can feel. I'm not sure how much of that is Carb, issues. Like I said, the secondaries don't open at all and it's leaking fuel out of just about every place it can and still run. So, I'm guessing the whole thing is one big vacuum leak. Probably why my secondaries won't open. If any of you sould help me out with troubleshooting for the fuel tank selector or the secondarie issue with the carb. or pulling the rear brake drums it would be very much appreciated. I also have the brake grabbing issue that I've read about with these trucks in the rear brakes. I just re-packed my front wheel bearings and put new pads on the front brakes so that area is all good. From what I can tell it needs new balljoints and tierod ends, too. One of the previous owners put a very stupid or cheap exhaust system on it, too. It has 2.5" pipes running from the manifolds to the Cheesey (ballooned) turbo muffler. Then, it has tiny little 2" tailpipes exiting behind the rear wheels. As soon as I can afford it, I will be getting glasspacks or Flowmaster 40s with 2.5 inlets and outlets and 2.5" tailpipes put on. I'm guessing a 454 + small tailpipes = the "exploded" as my local muffler shop called them, mufflers. That could be part of my aparent lack of power, too. Bad air and fuel mixing on the way in and blocked up exhaust can't possibly make for a very happy 454...lol. I flipped the stock air cleaner lid for more air. That was an old trick I learned way back in the day. I'm not even sure if it's benefiting my truck at all or not. Oh, also, does anybody know what a truck set up like mine would have for a rear ring and pinion gear ratio. I can jack it up and do the old count DS to tire revolutions and figure it out for myself but, I was just curious if anybody knew. I guess that's about it for now. My name is Brian Buchanan and I live in Oak Harbor, Washington. I am a 24 year Navy Chief Petty Officer. I will be retiring this summer and going to work for the Northrop/Grumman Corporation as a Weapons Systems Instructor (government contractor) on the new EA-18G growler tactical electronic attack jet fighter aircraft. Thank you so much ahead of time for any help I get. I will definitely share what I learn as I tackle my issues with this truck so others can learn from my wrenching.