Flex plate bolt confusion

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KJoeZ61

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I have a 71 with a 360 that I am getting ready to pull the engine for other reasons. However one reason was because of a horrible noise that sounded like it was internal from the engine. When I got to the point of removing the bolts from the flex plate to converter, each was almost a whole turn loose! I turned each one out by hand! And they looked beat up on the head!
Shouldn't they be torqued down and use red lok tight. I have seen 22 lbs, 75 lbs and this flexplate bolts which makes no sense to me.
 
22lbs., flexplate to converter, 75lbs., flexplate to crank. The thread You reference is discussing interference when the crank bolts touch the face of the converter. This can
happen if one tries using non-OE bolts, tries to use flywheel instead of flexplate bolts, or the converter is aftermarket & shaped differently in that area. There should always
be room there, and the converter should have a gap of a good 1/8-3/16" easy to the flexplate after installing the trans., You should have to work it forward to get it touching
the bolt lugs.................
 
Torque of the converter bolts is going to depend on the thread size......there two size threads...5/16 or 7/16.....
 
I have a 71 with a 360 that I am getting ready to pull the engine for other reasons. However one reason was because of a horrible noise that sounded like it was internal from the engine. When I got to the point of removing the bolts from the flex plate to converter, each was almost a whole turn loose! I turned each one out by hand! And they looked beat up on the head!
Shouldn't they be torqued down and use red lok tight. I have seen 22 lbs, 75 lbs and this flexplate bolts which makes no sense to me.
don't recommend red loctite, if you ever want to take it apart again. blue should be just fine
 

If the flex plate bounced and banged on those bolts, check the holes. They may be egg shaped. How much is too much? That's your judgement call. Even if you consider minimal egg shape not enough for concern, do file away the burr rolled up on the holes edge so the surfaces mate flat. To torque on a burr wouldn't stay.
 
Yes, but not all Locktite applications have the same strength. I too have removed fasteners that had be secured with red locktite; a small dab is literally weaker. But I don't use red generally anymore.
most fine thread fasteners do not require loctite at all, when properly torqued. The pitch of the threads provides a self locking feature when properly torqued. I have never used any loctite, on dozens of occasions, on any torque converter bolts, and never had them come loose. The key is to properly tighten them.
Now if the OP has some errant vibration problems, I suggest solving those, too.
 
Red loctite will come apart again... I've used it before...

Hey, im not making this $hit up. Read this:
Overview of Loctite Threadlockers & Colors


I used to design key brake interlock cables back in the early 90's, the Loctite rep gave me these free samples to test for one of our applications...

(Of course the free samples found their way home when I was done with my work with them and I still have them)....

I tested all of them for our application and NONE of them required any heat to remove... I did it with a torque wrench to see which one held the strongest...

Here they are in order of strength:

DSC02601 B.JPG
 
I used to design key brake interlock cables back in the early 90's, the Loctite rep gave me these free samples to test for one of our applications...

(Of course the free samples found their way home when I was done with my work with them and I still have them)....

I tested all of them for our application and NONE of them required any heat to remove... I did it with a torque wrench to see which one held the strongest...

Here they are in order of strength:

View attachment 1715091390
there are a lot of variables, how clean the threads are, what type of threads, how much threadlocker you use, etc. If you choose to ignore the manufacturer instructions, that's your problem. Essentially, telling somebody else to ignore the manufacturer instructions is rather reckless.
I made the mistake 45 years ago, putting red loctite on a SBM water pump bypass manifold fitting, and I had to destroy the fitting when I went to remove it. I wouldn't touch that stuff. It's unnecessary and overkill.
I have no problem with the blue stuff.
 
there are a lot of variables, how clean the threads are, what type of threads, how much threadlocker you use, etc. If you choose to ignore the manufacturer instructions, that's your problem. Essentially, telling somebody else to ignore the manufacturer instructions is rather reckless.
I made the mistake 45 years ago, putting red loctite on a SBM water pump bypass manifold fitting, and I had to destroy the fitting when I went to remove it. I wouldn't touch that stuff. It's unnecessary and overkill.
I have no problem with the blue stuff.

How can it be "reckless" when I have personally tested it and found the claims to be a little exaggerated???

Where does it say in writing from the manufacturer that the red stuff needs a torch to be removed???

I was dealing with the rep from Loctite, direct from the manufacturer... I got my info and recommendations straight from the horses mouth...

I did my own testing in a lab and evaluated the results first hand, and you tell me I'm reckless for sharing the information... :rolleyes: :wtf:
 
How can it be "reckless" when I have personally tested it and found the claims to be a little exaggerated???

Where does it say in writing from the manufacturer that the red stuff needs a torch to be removed???

I was dealing with the rep from Loctite, direct from the manufacturer... I got my info and recommendations straight from the horses mouth...

I did my own testing in a lab and evaluated the results first hand, and you tell me I'm reckless for sharing the information... :rolleyes: :wtf:
at the very least, you should warn somebody that it might require heat to remove. The responsible thing to do would be to caution him of the differing grades of red loctite.
 
at the very least, you should warn somebody that it might require heat to remove. The responsible thing to do would be to caution him of the differing grades of red loctite.

Please provide documentation from Loctite of the fact that heat is needed to remove the red loctite...

In my testing I did not require heat to remove any of them, so I don't think I have to warn anybody if there is no proof...

The 290 thread locker and the 680 retaining compound hold stronger and don't need heat to remove...

Get some yourself and make a youtube video of it if you are so adamant...
 
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Please provide documentation from Loctite of the fact that heat is needed to remove the red loctite...

In my testing I did not require heat to remove any of them, so I don't think I have to warn anybody if there is no proof...

The 290 thread locker and the 680 retaining compound hold stronger and don't need heat to remove...

Get some yourself and make a youtube video of it if you are so adamant...
try the link below:
Loctite Threadlocker Red 271 from Loctite Adhesives from Loctite Products Mobile Product Advisor. Expert guidance to find the best adhesive, glue and sealing solutions.
 
I have a 71 with a 360 that I am getting ready to pull the engine for other reasons. However one reason was because of a horrible noise that sounded like it was internal from the engine. When I got to the point of removing the bolts from the flex plate to converter, each was almost a whole turn loose! I turned each one out by hand! And they looked beat up on the head!
Shouldn't they be torqued down and use red lok tight. I have seen 22 lbs, 75 lbs and this flexplate bolts which makes no sense to me.

We had a similar situation. Beat on an old 340 for seven years and when we got around to pulling it, one convertor bolt was MISSING and one was not tight at all, the other two were still tight. My buddy and I just looked at each other with that WTF?!?! look. My 408 went back together with new ARP bolts and blue Loctite.
 
I guess it might come down to what you have and how much you use.
When I worked for Henkel we used the 271. I'd hit the bolt threads with brake cleaner and then hold the bolt in a horizontal position. At the midpoint of the threads, place two or three drops of loctite in the same spot, on top, and let it run down both sides of the bolt thread. Still holding it horizontal let the excess drip off the bottom, and assemble. We didn't treat the whole bolt thread.
When you take it apart, some of the loctite will curl out like a plastic string. You can clean the threads with a tap and a wire wheel, no big deal.
On NPT threads, it's not going to back out, so I would use neverseeze, teflon pipe dope or tape, because I may want to take it apart some day and I don't want it to corrode.
Loctite is neat stuff. Leave the lid off and it won't dry up, but remove the air and it will.
We also made the brake cleaner. It's good for cleaning grease spots out of clothing. You can tell by the smell, if you remember what an old Dry Cleaners smelled like.
 
Gonna have to agree with krazykuda on this one. I have never found the red loctite to be truly permanent, and I haven't used heat to loosen those fasteners either. I use both red and blue, typically I only use the red if both threads are steel and the fasteners are fairly large. Like, flywheel and flexplates bolts, for example.
 
And I suspect it depends on the bolt size and how it is applied. Put red on a 1" diameter bolt 100% up and down a 1" thread engagement length, and I bet it is time to heat it tor remove it. If you guys are like me, I put a just coupla drops on any bolt/nut, just enough to prevent loosening due to vibrations, and no more.
 
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