Magnum broken intake bolts?
- Thread starter 67Dart273
- Start date
-
273
Those bolts are one time use bolts. Maybe someone reused them at one time or another. They are torque to yeild, and not to be reused.
barracudadave67
Those bolts are one time use bolts. Maybe someone reused them at one time or another. They are torque to yeild, and not to be reused.
barracudadave67
mischiefdart
Well-Known Member
The bolts up front by the water outlets on the heads tend to corrode. I have reused all the magmun intake boltson jobs I have done. They are not torque to yield.
67Dart273
Well-Known Member
The ones up front are "it." interestingly, the ones in the rear are same, IE you turn the heads around, they are the same positions. I don't get it Guess those "new" vertical bolts weren't such a hot idea
nm9stheham
Well-Known Member
Yer just too strong, Del. LOL
67Dart273
Well-Known Member
I admit the FIRST one I broke was with the impact. Just never entered my mind. The OTHER two I was try'n to break them loose with 3/8 drive ratchet. Broke 'em right off. Reminded me of the old OEM bolts on the ol 62 Landcruiser FJ-40. I think every bolt on that thing was grade . (POINT) 5, er 1/2 er something. Lord they were soft
pishta
I know I'm right....
My first Honda car had head bolts that used a 10mm socket. Air cooled of course! Entire engine was 10 or 12 with 1 17mm chain tensioner. This "restored" one is missing the heater duct bellow...? Heater was right off the exhaust manifold. Pray you didnt have a leaking exhaust gasket, sleepy head!
Fo be honest ,Del.... Every unknown fastener,I have dealt with: Remove with hand tools, cautioned... I made the mistake on a Pontiac 455 long block, patience is the key, here... Soak it with penetration oil, hit some flame old school torch, in intervals.. The penetrating, heating cycled, will get those bastards loose ,Del....
67Dart273
Well-Known Member
They are badly corroded up in where they would have been in the manifold, in fact they pretty much broke real close to the head. Makes you wonder what is going on. When they came, it felt like they were loosening and turning. Actually it was the softened weakened bolt shearing off.
RAMM
Well-Known Member
Holy crap this ain't rocket science. First of all the intake bolts are just plain Jane 5/16" x 18 bolts NOT TTY. The outer 4 bolts (aerial view) corrode because they are not blind holes and are exposed to the elements from the top AND the bottom. All 8 inner bolts are open into the engine so they get splashed with oil and are bathed in engine oil vapors their entire life so they don't tend to corrode. J.Rob
Blue Grey Duster
Well-Known Member
Just visit your Ace Hardware and pick up SS or grade 8 or whatever, and get some neverseeze.
Remember the the torque sequence bolt pattern is a little different than an LA intake pattern.
Remember the the torque sequence bolt pattern is a little different than an LA intake pattern.
67Dart273
Well-Known Member
.............OK,...........how do you explain that since 1970 when I owned my first Mopar, I have NEVER broken an LA manifold bolt? Makes me wonder if these aren't susceptible to corrosion due to material or poor heat treating, etc. N' yeh, in my non-rocket-scienceness, I DO realize these are 5/16 and not 3/8
I haven't worked on a gob of Magnums, but have done a few and never seen this.
RAMM
Well-Known Member
I was emphasizing that they are not TTY. I also explained that the holes are open on the heads whereas the LA's are blind on the ends which means water/dirt/salt/ etc.. Cannot work at the bolt from the bottom. That is all. J.Rob
jos51700
Green Bearing thread connoisseur
To be fair, the modern art of failure analysis IS heavily rooted in aerospace....
And as someone that kinda does FA for a living, a picture goes a long way because this is a little unusual. I've worked on a few Magnums and had no issues.
Could be the bolt head popped off the shank. Could be twisted off at the threads. Could be a crack at the thread root that couldn't handle any torsion.
And a picture can offer a lot of info into that for those of us that care to know. Even tty fasteners shouldn't be snapping and the modern OEM fasteners are generally quite good. With three Magnums in the stable, I have a vested interest in the OP's issue.
67Dart273
Well-Known Member
I tossed the bolt heads. When I get to it I'll try and post a shot or two. And if things ain't bad enough, I dragged home another 5.2 today. 5 speed, transfer case, and that gives me a good flywheel "maybe". This one is sposed to run, I'll be into it next few days. Going to be a record hot memorial day here, hottest in 22 or some years the wx girl said
-
