70 Skylark 455 radiator shroud alignment

Discussion in 'The Big Chill' started by BuickBarr, Apr 27, 2019.

  1. BuickBarr

    BuickBarr Well-Known Member

    I'm narrowing down an overheating heating problem on a car that is relatively new to me and ran into a radiator shroud alignment issue.

    My shroud looks to be a fiberglass remake. Adjusted all the way up fan clearance is tighter at the top by 1/2" vs the bottom. Clearance is also off to one side about the same. The engine seems to be sitting correctly however I will say the motor mount bolts were a bitch to get in after my recent rebuild and the trans crossmember is farther back than a normal position so something funky may be going on there.

    Any suggestions on where to look next?
     

    Attached Files:

  2. Matt Knutson

    Matt Knutson Well-Known Member

    Is your core support shimmed / aligned properly? More pictures will be helpful. What transmission are you using?
     
  3. BuickBarr

    BuickBarr Well-Known Member

    Thanks Matt for the reminder to check the simple things first.

    Hard to get a clear pic but the core support bushings are squashed and cracked so that is probably contributing to being tight on top. I happen to have a brand new set of bushings left over from the last car so they will be going in soon.

    Looking closer the front is very slightly racked towards the drivers side. Also thre are shims between the passenger fender and core support but no shims on the driver's side. Looks like a front end sheet metal alignment is in the future.

    Trans is TH400.
     

    Attached Files:

  4. BuickBarr

    BuickBarr Well-Known Member

    More issues found as I dig into this car. Because of the over heating problem I had bought a TA water pump a few months back. Getting ready to install it and just realized I bought a short one while the one on my early 70 (plastic rad cover, clear overflow) non original 455 is currently long. Fan was buried into the shroud by about 3/8" so that could be corrected by a short pump however that will cause pulleys and more to change.

    Here's my current situation:

    71 up parts:
    1235778 Water pump pulley
    1235777 crank pulley
    1235837 alt brace

    70 parts:
    1961408 alt pulley (on a 70 alt)
    1386935 ps pulley
    Ps aluminum bracket and plates (I think 70)
    Shroud

    Unknown:
    Upper ac bracket (has a hole but not threaded for ground screw)
    Lower ac/alt bracket

    The appears to be no belt alignment issues although I do remember having to fight the upper ac bracket when putting it on.

    So I'm at a crossroads...

    Buy a long TA pump and maybe a 71 shroud
    or
    Buy 70 wp/crank pulleys and alt bracket (but will that throw off ac and ps alignment)?

    Any ideas?
     
  5. copperheadgs1

    copperheadgs1 copperheadgs1

    The long water pump puts the fan too far into a 70 shroud. How is your fan clutch?
     
  6. copperheadgs1

    copperheadgs1 copperheadgs1

    I am guessing someone used a long tail turbo 400 transmission if crossmember back far. Probably a custom driveshaft. I would also suggest getting everything all one year. You are mixing and matching. That is nothing but trouble.
     
  7. copperheadgs1

    copperheadgs1 copperheadgs1

    You also have a small pulley AC compressor. GS had big pulley
     
  8. copperheadgs1

    copperheadgs1 copperheadgs1

    Get a 71 shroud or get all 70 Pulleys
     
  9. copperheadgs1

    copperheadgs1 copperheadgs1

    Short water pump for 70 pulleys
     
    Last edited: May 13, 2019
  10. BuickBarr

    BuickBarr Well-Known Member

    Thanks. Didn't even think about the long tail TH400 possibility. Will have to check that out tonight. That would make sense but also be crazy.

    I'm hoping 70 wp and crank pulleys will be the fix since I already have the short TA wp pump. Will the be any issues with the AC upper and lower brackets?
     
  11. copperheadgs1

    copperheadgs1 copperheadgs1

    Yes, they are all different in 70
     
  12. copperheadgs1

    copperheadgs1 copperheadgs1

    Put an ad in here. Plenty aroind
     
  13. copperheadgs1

    copperheadgs1 copperheadgs1

    Alternator arm is different in 70 too
     
  14. BuickBarr

    BuickBarr Well-Known Member

    Last question, any issues on the power steering side? I have the aluminum bracket plus steel plates.
     
  15. copperheadgs1

    copperheadgs1 copperheadgs1

    That’s a 70 set up. Make sure it’s all 455. Actually big aluminum piece is same for a 350. Two plates are 455.
     
    BuickBarr likes this.
  16. copperheadgs1

    copperheadgs1 copperheadgs1

    8C857DBB-4204-4F56-9D5A-EC371AF34C98.jpeg This is a correct 70 set up. Notice the big pulley AC compressor and look at the huge gap above pulley on alternator for AC belt. Yours is in pulley. Big difference for 70 stuff.
     
  17. BuickBarr

    BuickBarr Well-Known Member

    Nice pic!

    My trans is long! A '72 "BC" which the code chart says is "455 all others". Dealing with that will have to wait.
     

    Attached Files:

  18. copperheadgs1

    copperheadgs1 copperheadgs1

    The short shaft section is about 4-6 inches if I remember and long shaft 9-10”. It’s very noticeable.
     
  19. BuickBarr

    BuickBarr Well-Known Member

    Yes, tail is 9"
     
  20. copperheadgs1

    copperheadgs1 copperheadgs1

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