Brakes and engine issue (video reference inside)

Discussion in 'Troubleshooting & Diagnosis' started by 78rallysport, Oct 19, 2017.

  1. 78rallysport

    78rallysport Veteran Member

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    Jan 5, 2009
    Los Angeles, CA
    Hello to the Nastyz28 community. I have not posted for a couple years probably. I'm trying to get my 78 rallysport 350/th350 back on the road. I have a few minor issues that I'm having a little trouble with.

    A year or two ago I replaced some key parts to my brake system. Master cylinder, brake booster, rear drums, drum shoes, drum hardware/springs, drum brake cylinder. At the time my breaks were really soft. I think it was my brake booster or master cylinder leaking, so I just figured I would replace all the rear brakes to be thorough, (the fronts had been redone within the last 5-10,000 miles.) The rears weren't dead, they were just really worn, so I figured I'd replace them.

    The problem is that the driver side brake drum is really hard to put on, like I had to hammer it on, then tighten the lugs to get it flush, so basically when I drive it, it's like that wheel is always braking, even when I'm not.

    I tried rebuilding it 2 or 3 times. Tried switching drums. The star adjuster for the shoes is all the way open. One thing I've been thinking is maybe it has something to do with the emergency break. Maybe I adjusted it to make it fit? I don't remember. Also my exhaust is kind of hanging low. I'm wondering if possibly my exhaust could be hanging on the emergency brake cables causing them to be activated? Has anyone heard of this?

    I've research the threads. Researched a lot. Just thought I'd share and maybe someone might have some insight. Honestly, I always heard people complain about doing drums, but when I was doing it I felt like it was really easy, like doing a puzzle. (of course now I cant figure out this problem, so what I felt was easy has turned into a frustration.) Had this old mechanic neighbor of mine look at it. He said it looked like everything was in the right place.. He suggested I sand down the braking material on the shoes, which I did and helped it not to be as tight of a fitment on the drum. Any ideas or thoughts from anyone would be appreciated.


    Both L and R wheels are suspended off the ground in this video.

    Also I have a little engine issue. It overheated pretty bad once. Bad enough to warp my flexplate, which was a pain to change out. The engine still runs and everything, just makes a clicking sound from the valvetrain and has a little after fire out the exhaust. Maybe a valve is getting stuck, or damaged/broke. I tried taking the valves covers off to look at the valvetrain, everything looked relatively fine, I didn't notice any significant play between a rocker and pushrod, one might have seemed slightly more loose than it should have been, but I'm no pro, so I don't know. Again, any opinions appreciated.


    In this video you can hear the clicking while I film under the hood. I think it's a valvetrain issue, because it seems to cycle with the engine firing cycle. Then you can hear an afterfire right when I walk over to the exhaust at about 00:19 seconds and later at 00:53/54. Any ideas on what this might be would be helpful. Also, how serious do you think this is? Cause the engine still runs, like i could just drive it and it wouldnt bother me, I just dont want to if it could cause some catastrophic failure that would wreck my whole engine.

    If you read all this and/or reply, just want to say thanks. Sorry it's so long.
     
    Last edited: Oct 19, 2017
  2. Twisted_Metal

    Twisted_Metal Moderator Staff Member Lifetime Gold Member

    25,263
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    Feb 26, 2004
    Bloomington, MN
    The rear shoes are long and short. (Long ones go to the rear of the car.)

    If you put two long ones on one side and two short ones on the other... The long ones will hang up.

    Or... Your exhaust could be pulling the e-brake cable.
     
  3. 80sz

    80sz Veteran Member

    2,153
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    Feb 2, 2014
    Buffalo,n.y.
    It dont sound good does it. It might be a exhaust leak? You didnt rev it up.
     
  4. djorgensen3

    djorgensen3 Veteran Member

    248
    1
    Oct 15, 2009
    Peoria, Az
    "The star adjuster for the shoes is all the way open"

    You stated that the star adjuster is all the way open. Close that thing up...make it small. You only need to open it up enough for the shoes to touch the drum. You shoudn't have to hammer the drum on at all.
     
  5. larrylarry

    larrylarry Veteran Member

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    Dec 22, 2011
    San Antonio Tx
    Look for a cracked exhaust manifold, really sounds like that.
     
  6. RS1979

    RS1979 Veteran Member Lifetime Gold Member

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    Jun 18, 2013
    Memphis, TN
    I agree with Larry. That does sound like an exhaust leak.
     
  7. 78rallysport

    78rallysport Veteran Member

    117
    0
    Jan 5, 2009
    Los Angeles, CA
    Thank you, everyone for your responses.

    To address some comments and give more explanantion:
    -When I rebuilt the drums I did one side at a time, so I don't think I switched any hardware from L to R.
    -Sorry, I meant to say the star adjuster is adjusted, so that the shoes are in as much as possible -><- to give as much clearance so that they are not pushing out. One thing that was weird is that I had trouble getting them to touch the little metal bolt type pieces that stick out of the cylinder. I put a clamp on them to try to squish them close together but it's like they're barely making contact with the metal that sticks out of the cylinder.
    -When I rev it up, the ticking sound seems to be consistent with the engine firing cycle. The plunky-pop sound out the back seems like it could be worsened as engine temp increases, but I haven't really run it for more than 5 minutes at a time, usually no more than around 35mph, so I'm not totally sure.
    -It has dual exhaust, with no cross over, so the plunky pop sound (which I assumed is an after fire, as another mechanic told me that a backfire comes out the carb side, and after-fire out the exhaust) is definitely on the left. Could that plunky-pop sound out the exhaust be from the exhaust leak? At this point I would not put it past the car to have some engine issue as well as an exhaust leak. I suppose an engine overheating could cause a manifold crack, so that could be a possibility.

    All your feedback has really given me some good direction. Next time I try to mess with it, I will take more pictures and video to show more. Maybe this weekend or next week, Until then, thanks and take care.
     
  8. RS1979

    RS1979 Veteran Member Lifetime Gold Member

    2,445
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    Jun 18, 2013
    Memphis, TN
    An exhaust leak can echo through the tail pipe.
     
  9. larrylarry

    larrylarry Veteran Member

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    Dec 22, 2011
    San Antonio Tx
    ^^^ And they seem to always be leaking where you can’t see it. Sometimes you have to get your fingers burnt by running them along the manifold & pipes feeling for puffs of exhaust gas
     
  10. hogg

    hogg Veteran Member

    3,083
    24
    Dec 29, 2000
    pegram,tn.,cheatam
    tape small pice of rag on a stick,see if it move when close to leak
     

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