My 1969 GS400

Discussion in 'Members Rides' started by FLGS400, Nov 30, 2020.

  1. Stage 2 iron

    Stage 2 iron 472 IRON HEAD STAGE 2

    Hopefully your new radiator will lower the temperature if not you may want to try a TA performance high-performance performance water pump.
    FLGS400 likes this.
  2. FLGS400

    FLGS400 Gold Level Contributor

    Yes. If that is the case, the timing cover will be replaced with a TA Performance one, too. That will take care of the oil leak at the front seal. Plus, the stock timing cover is pretty corroded where the lower radiator hose connects to it.
    Stage 2 iron likes this.
  3. Stage 2 iron

    Stage 2 iron 472 IRON HEAD STAGE 2

    I think Buick missed the boat in 69 not having that color available. Hey I still have that sandalwood 15 inch rally steering wheel available.
    PGSS and FLGS400 like this.
  4. FLGS400

    FLGS400 Gold Level Contributor

    Well last night, I finally had another opportunity to work on the car. Installed the AC Delco, Roadmaster starter, new dipstick and tube, and new crankcase breather and hose.

    The starter was a pretty easy swap, though it did require a spacer for the smaller bolt, a new terminal on 2 of the small wires that go to the large post, and a modification to the terminal on the pink wire that goes to the small post (enlarge the hole in it). It's hard to believe that little thing cranks the 400 with ease! I just have to get used to the different sound of it now. LOL

    Sorry, I didn't take any pictures.

    Next it's on to the Cold Case radiator, upper and lower hoses, and thermostat housing replacement!
  5. Max Damage

    Max Damage I'm Working on it!

    I know that thermostat outlet housing looks like an easy get, but maybe use the search function here first to see all the problems people have had with this?

    I recently replaced mine with the T/A version, and it took me three attempts to get it to seal! This finally included making my own cork gasket and using "special" gasket adhesive (3M weather-strip stuff).
  6. FLGS400

    FLGS400 Gold Level Contributor

    This will be my 3rd attempt as well! This time I am replacing the housing. The one on it now is the original and has a LOT of deep pitting where the bypass hose connects. I told myself if it leaks again, I would replace it. I was able to pick up a couple of used 455 ones from 1969RIVI, that are in much better shape. Larry gave me some tips on installing them too. If it leaks again, I'm going to try your method!
  7. FLGS400

    FLGS400 Gold Level Contributor

    So, over Memorial Day weekend, I replaced the stock radiator with the Cold Case 2-core, replaced the thermostat housing with one of the used ones I got from 1969RIVI, and replaced the upper and lower hoses with AC Delco ones. I finally took it for a drive tonight, to pick up dinner. It was great!!!! After a few miles, the temperature never got over 180, even while sitting in Checker's drive through, waiting on my food. I'm so stoked!! For the first few miles, the temperature jumped around quite a bit. I'm sure it was just the system working out the air pockets after the thermostat fully opened.

    Looks like the thermostat housing leak has been fixed now too. Thanks to you all for the tips on installing! I need to go check it again now and I'm sure I'll have to add some more coolant.

    I did have to make a few mods to help the radiator fit better. Nothing that couldn't be reversed if someone wanted to put it back to an original radiator. Had to swap the rubber bushings at the top, so the raised part was to the inside, and made some 1/2 spacers for the fan shroud, so it would not rub on the radiator. The cold Case Radiator sits about 1/2" closer to the fan than the stock one did. It's that much thicker at the core part. The bottom of the shroud fit right into the tabs with no problem. I added some edge protectors to the core support, made form split 3/16 vacuum line, to protect the radiator, too. Being thicker than the original, the front edges of the tanks were right up against that edge. The rubber bushings at the bottom were close enough to make work, as they were.

    Next thing on the list is to fix the fuel gauge. For some reason it quit working after I replaced the starter. I think it's just a coincidental though It wouldn't make sense that the starter has anything to do with it. I'm thinking that the sending unit took a crap, as the gauge just goes as far to the top as possible, when you turn on the key. I ordered a new sending unit from Summit with some parts for the other car that I needed (to make the free shipping minimum). If it's just a ground issue, I'll keep the new one in case of the eventual failure. Anyone use a sending unit from Autometal Direct yet? That's the one I bought, due to the lower profile of where the 3/8 line exits the unit. I read on here that others have had problems with the Spectra units being too tall a profile.
    Max Damage likes this.
  8. FLGS400

    FLGS400 Gold Level Contributor

    Here are some picture of the finished product. And the thermostat housing did not leak!

    20210609_195610.jpg 20210609_195521.jpg 20210609_195540.jpg
    MRP and Max Damage like this.
  9. FLGS400

    FLGS400 Gold Level Contributor

    Just in case anyone was wondering, I ended up installing the new sending unit form Autometal Direct. It also seems to have a slightly taller profile on the fuel line, that hits the trunk floor when the tank is installed, just like what I heard about the Spectra unit. I was able to gently bend the line down a bit and that helped.

    At least now the gauge works!
    Max Damage likes this.

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