Manifold Nuts coming loose

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vtdeucedriver
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Manifold Nuts coming loose

Post by vtdeucedriver »

Hey all,
Any of you had problems with your manifold hardware coming loose?? I put it all together with new harware and torqued everything per the book. A year ago or more I had a issue starting and heard a weird whistle and found that the intake and exhaust nuts were loose so I ran em back down. Well again last week I was starting to go over the truck for my spring inspection and just thought I would put a wrench to them and AGAIN, they had backed off. Just wondering if anyone else has had issues.
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HingsingM37
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Re: Manifold Nuts coming loose

Post by HingsingM37 »

I have not had this issue although I was always expecting it given the low 20ft-lb spec for torque, mine have stayed tight. I believe I re-torqued them once after my initial engine run up and they have been fine going on 4 years now. Assuming you have the correct hardware (conical lock nuts for the exhaust, brass washers, studs correct ect.) which I am sure you do, and all else is in order with the manifolds, perhaps try another torque wrench to ensure accuracy. I am sure others will chime in with some thoughts :wink:
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Re: Manifold Nuts coming loose

Post by milstencil »

Hey Jeff :!:
I hate to ask this of a "world class" aircraft mechanic but,
do you have the nuts on the "right" way :?:
That is, with the castellated part facing in so that it
compresses against the stud when tightened against the counted sunk
brass washer locking it in place.
Or, are the studs backing out of the block :?:
Rick
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vtdeucedriver
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Re: Manifold Nuts coming loose

Post by vtdeucedriver »

Haha. world class is a bit far out there. But yep there on the right way.
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1951 M37
1954 M37
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1968 M54A2C
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m37jarhead
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Re: Manifold Nuts coming loose

Post by m37jarhead »

Scared me..... I'm going to check my nuts tomorrow.
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Re: Manifold Nuts coming loose

Post by Monkey Man »

m37jarhead wrote:Scared me..... I'm going to check my nuts tomorrow.
JB
Wellll......Any good doctor will tell you to check your nuts on a regular basis.... 8)

MM :D
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m37jarhead
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Re: Manifold Nuts coming loose

Post by m37jarhead »

Monkey Man wrote:
m37jarhead wrote:Scared me..... I'm going to check my nuts tomorrow.
JB
Wellll......Any good doctor will tell you to check your nuts on a regular basis.... 8)

MM :D
Thanks MM, I did check my nuts this morning then went out to the shop and checked
the nuts on the M37 manifold. Both sets of nuts were loose but could only tighten
the ones on the manifold. Any suggestions?
Jerry
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Re: Manifold Nuts coming loose

Post by w30bob »

Jerry,

Quit while you're ahead. :mrgreen:

later,
bob
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Re: Manifold Nuts coming loose

Post by Monkey Man »

m37jarhead wrote:
Monkey Man wrote:
m37jarhead wrote:Scared me..... I'm going to check my nuts tomorrow.
JB
Wellll......Any good doctor will tell you to check your nuts on a regular basis.... 8)

MM :D
Thanks MM, I did check my nuts this morning then went out to the shop and checked
the nuts on the M37 manifold. Both sets of nuts were loose but could only tighten
the ones on the manifold. Any suggestions?
Jerry
Yep, The Female of the species are especially equipped for tightening nuts, not sure as to wether or not you have "Wife" or Girlfriend" Model equipment but either should suffice to get a more than satisfactory result.
However, a word of warning on operating procedures...... IF you currently have the "Wife" model then do not be tempted to re-use the "Girlfriend" model, the 2 are completely incompatible and may result in a Serious malfunction causing the nuts to be removed completely..... :shock:

MM :D
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Re: Manifold Nuts coming loose

Post by Brigand »

MM wrote:Yep, The Female of the species are especially equipped for tightening nuts, not sure as to wether or not you have "Wife" or Girlfriend" Model equipment but either should suffice to get a more than satisfactory result.
However, a word of warning on operating procedures...... IF you currently have the "Wife" model then do not be tempted to re-use the "Girlfriend" model, the 2 are completely incompatible and may result in a Serious malfunction causing the nuts to be removed completely..... :shock:

MM :D
Tony, Is that from the same developers who came up with "boyfriend" and "husband" programs you were discussing in another part of the forum?
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Re: Manifold Nuts coming loose

Post by Brigand »

vtdeucedriver wrote:Hey all,
Any of you had problems with your manifold hardware coming loose?? I put it all together with new harware and torqued everything per the book. A year ago or more I had a issue starting and heard a weird whistle and found that the intake and exhaust nuts were loose so I ran em back down. Well again last week I was starting to go over the truck for my spring inspection and just thought I would put a wrench to them and AGAIN, they had backed off. Just wondering if anyone else has had issues.
I had a similar problem with a non Dodge. I cured it by double nutting the manifold studs using brass nuts. I hope that helps.
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w30bob
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Re: Manifold Nuts coming loose

Post by w30bob »

VT,

I was thinking about your problem today....the one with the manifold nuts, not yours, and have to ask why you don't just put a little blue Locktite on the nuts. I believe the blue is temperature rated high enough, but I can check the package later if you like. A fresh dab of locktite won't interfere with the torque reading until it sets up, and it doesn't interfere with the castellated snout compressing and expanding when the manifold heat cycles. Just a thought.

regards,
bob
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Re: Manifold Nuts coming loose

Post by Monkey Man »

MM wrote:
Brigand wrote:Yep, The Female of the species are especially equipped for tightening nuts, not sure as to wether or not you have "Wife" or Girlfriend" Model equipment but either should suffice to get a more than satisfactory result.
However, a word of warning on operating procedures...... IF you currently have the "Wife" model then do not be tempted to re-use the "Girlfriend" model, the 2 are completely incompatible and may result in a Serious malfunction causing the nuts to be removed completely..... :shock:

MM :D
Tony, Is that from the same developers who came up with "boyfriend" and "husband" programs you were discussing in another part of the forum?
No, "Husband" and "Boyfriend" are Firmware versions loaded (otherwise known as "Booted") into the harware of the Male of the species to change the functionality of the unit that already has an inclusive operating system called "Single", this is also known as "Free" to some as it comes pre-installed at no cost. The Female chassis comes pre-loaded with "Girlfriend" as they are pretty well disposed to attatching themselves to a Male at any point in their early operation whereas male chassis units tend to shun this function. So, the crux of it is "Boyfriend" and "Husband" are regarded as full Firmware Upgrades and are usually not Reversible once loaded and the male chassis can only carry one version of the firmware as the memory capacity is severely limited and even if "Husband" is placed in a "Free" mode situation it will usuall behave the same and look for the "Wife" Hardware. "Wife" However can revert to "Girlfriend" at any point as both versions reside in the same hardware once placed into a "Free" mode situation but if "Wife" can see it's "Husband" hardware app installed it becomes inversely polarised to the "Girlfriend" equipped Female Chassis units.....
I hope this clears it all up for you Bob.

MM :D
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vtdeucedriver
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Re: Manifold Nuts coming loose

Post by vtdeucedriver »

w30bob wrote:VT,

I was thinking about your problem today....the one with the manifold nuts, not yours, and have to ask why you don't just put a little blue Locktite on the nuts. I believe the blue is temperature rated high enough, but I can check the package later if you like. A fresh dab of locktite won't interfere with the torque reading until it sets up, and it doesn't interfere with the castellated snout compressing and expanding when the manifold heat cycles. Just a thought.

regards,
bob
Bob it was my thought also!! I am looking at a valve adjustment before too long and that was definatly going to take place. Will keep you posted on what I find. Cant wait to use my brand new set of Snap-on thin wrenches :D
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1951 M37
1954 M37
1953 M62
1967 M54A1C
1968 M54A2C
1968 M52A2
1966 M151A1
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Re: Manifold Nuts coming loose

Post by Kaegi »

a few things to consider:

1. are the intake and manifold botled together well and are the mating surfaces to engine prefectly aligned with each other?
2. are you using at least grade 5 nuts and the correct washers?
3. Even the grade 5 yhou get these days is chinese junk so I buy grade 8 for that job usually. Or i go get the "high nuts' that are a bit taller than regular from Tacoma screw and they are US made grade 5.
4. the threads on the studs could be worn out.
5. did you start ightening in the correct sequence? from center out.

I tighten them to probalby around 35Lbs on the non conical nuts.
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