1970-72 Skylark Front Clip alignment

Discussion in 'Chassis restoration' started by schwemf, Aug 2, 2020.

  1. schwemf

    schwemf Mike Schweitzer

    The Buick Chassis manual Group 110 details alignment of the front sheet metal, i.e. the fenders, hood, and radiator support. For years I've struggled to make sense of these instructions, in part due to the terminology used for the four most critical bolts.

    These four bolts include two on the driver's side and two on the passenger's. One pair is referred to by various names in the manual, including "front of dash directly behind hood hinge", "front of dash slightly below the hood hinge", "vertical fender to body attachment point". I've included a picture of this bolt as it appears on the right/passenger's side. Driver's side is similar.

    The other two bolts are referred to as the "chassis sheet metal to frame bolts", which are the bolts through the body bushings on which the radiator support attaches to the frame. I've included a picture of this bolt from the right/passenger's side as well.

    IMG_20200802_135153377.jpg IMG_20200802_135201799.jpg

    I won't duplicate the excellent instructions in the chassis manual, except to say that each "front of dash directly behind hood hinge" bolt governs the gap between the front edge of the door and the rear of the fender. Add shims at this bolt to increase this gap. Add shims at the "chassis sheet metal to frame bolt" to make the gap parallel, by tilting the fender "in" towards the door at the top.

    The "chassis sheet metal to frame bolts" allow the radiator support to be moved right or left to square the hood opening. I've found it extremely helpful to measure the gap between the fenders at three locations (top rear of fender, adjacent to rear of hood; in front of hood hinge; at front-most bolt at radiator upper tie bar), as well as the diagonals (from bolt head at "shroud top area" to front-inner tip of fender). Use a pry bar between the frame rail and radiator support to adjust.

    I hope these clarifications will help! I've actually taken a three week class in sheet metal alignment, back in 1986, and worked as an amateur restoring GS' for forty years. Only now with the above information do I feel confident in this task!
     
  2. schwemf

    schwemf Mike Schweitzer

    Worn hood hinges can have a big effect on hood-to-fender alignment. One set of hinges that I tried resulted in the hood landing on the fender. Another set resulted in the hood landing on the opposite fender! When I say "on the fender" I mean "all along the fender" and not just at the front corner which is common when adjusting the hood.

    So off to my stash of nine sets of used Buick A body hinges, mostly 1970-72. Following instructions that I learned here on the board, I popped off the springs, secured each hinge in a vice, and checked for play. All but five hinges had significant play! Using the best ones I was able to get a pretty decent fit. I did send a couple sets off to be rebuilt, but the rebuilt hinges proved to be no better than my lightly-worn and mostly play-free survivors. The pictures shown are with the rebuilt hinges.

    IMG_20201001_120632159.jpg IMG_20201001_120638873.jpg IMG_20201001_120651193.jpg IMG_20201001_120702611.jpg
     
    Dano likes this.
  3. Max Damage

    Max Damage Well-Known Member

    Thanks Mike. This is helpful.
     
  4. TimR

    TimR Nutcase at large

    The real key is patience. If you are painting a car put it all together BEFORE the paint goes on, get it all lined up to your satisfaction, then take pictures and notes of shims, etc so once painted it all goes back together cleanly. Even then you will find it hard to get back to where you were. Good hood hinges are key for the hood obviously, and well spaced gaps are good...larger even spaced gaps look better than tight gaps that are mismatched. These cars were not well done when new as you know. No paint play around and learn the car, you can squeeze the fender outwards to fit door better with less shims on the bottom or shim the rad support bushings to line up the fender/door gaps better top to bottom. You will not get perfection unless you start welding edges etc...sheetmetal alignment is the art of compromise. Take your time, have some fun, don't forget they flex too (verts especially!) so keep things within reason.

    http://fixjet.ca/done.html
     
    Dano likes this.
  5. Dano

    Dano Platinum Level Contributor

    Exactly. I've walked out at night not knowing how I was going to proceed to fix a certain gap and by the next night had a plan. The procedure in the body manual is a good starting point. To get it perfect, as Tim said, usually requires at least cutting spot welds (if you have replacement fenders this will be necessary).
     
    TimR likes this.
  6. TimR

    TimR Nutcase at large

    I learned that lesson the hard way many many years ago, what could go wrong with new sheetmetal, right? :rolleyes:
     
    Dano likes this.
  7. Dano

    Dano Platinum Level Contributor

    Or even new wheelwell moldings - Nothing like trying to force fit them on a newly painted car. Back before we really knew about the fender issue (btw, amazing how many used replacement fenders I've seen), we'd see a lot of cars at the Nationals with misaligned hoods (late 80's/early 90's). Of course they'd look great at the show with the hoods open.

    The right way to do this IMHO is to literally assemble the entire car, drive it, sort out any issues, they blow it back apart to paint & reassemble.
     
    schwemf likes this.
  8. stump puller455

    stump puller455 1970 GS 455

    Thanks for the useful post mike !
     
  9. schwemf

    schwemf Mike Schweitzer

    Not being able to lower the rear of the hood sufficiently, to align with top rear of the fenders, is another symptom of worn hood hinges. At maximum "down" adjustment at the rear (created by pushing the hood up at the front/nose), my worn hinges just barely got the hood flush with the rear top edge of the fenders. With the rebuilt hinges, I can drop the hood below flush with the fenders.

    I believe this can be attributed to gravity pushing the hood down, with the hood pivoting at the hinge. The front of the hood drops, and the rear of the hood raises. Play at the hinge pivot points simply allows the hood to travel further upward at the rear.
     
  10. schwemf

    schwemf Mike Schweitzer

    Finally, the middle of the hood was about 5/16" higher than the fender, on the passenger's side, but flush to the fender at both the front and rear. Using blocks of wood under the hood bracing to support the corners, a two-foot long 2x4 at the crown of the hood, and a 3 pound sledge, I remedied this with a dozen very hard blows along the high points of the hood.
     

    Attached Files:

  11. Matt Knutson

    Matt Knutson Well-Known Member

    Mike,

    I sounds to me like you should have drilled the spot welds on the fender and let the fender come up to the hood lines. No three pound sledge required.

    Matt
     

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