Threadlocker to Flexplate Bolts

[66 Sat]

Hi, we recently re-installed the engine/transmission in my car and I've noticed my father-in-law used Permatex Low-Strength threadlocker (Purple) on the torque convertor to flexplate bolts, rather than the Medium (Blue) or High (Red). The bolts were all torqued to spec.
My question is has anyone had bolts come loose after using the low strength stuff? He would have also used it on the flexplate to engine bolts which is lot harder to fix than the torque convertor bolts. I realise now we should have used the blue (hence my question), but what does everyone reckon?

 

[Cranky]

I've had bolts come loose using red!

 

[vintage chromoly]

I use red for just about everything.

 

[66 Sat]

This isn't a race car, only a cruiser with the odd quarter mile pass. What about the flexplate to engine bolts? They are the ones I'm most concerned about as it's a major pita to fix. I actually have the red and blue in my garage, but he brought some over with him and I didn't notice what he'd used until after the engine was in.

 

[Bee1971]

On my 1971 Superbee , when I rebuilt the #s matching motor back in the mid 90s

I didn't use any locktite on the cam bolt , flexplate to crank and flexplate to converter

Was nice pulling everything apart

Street use only

How do I remember this - Well it just got rebuilt again into a Stroker Kit , and the #s Transmission just got rebuilt also this past fall

Zero issues with those bolts mentioned after 25 years with no locktite

However I did replace all the bolts with ARP Hardware this time around

 

[PurpleBeeper]

In my opinion, I wouldn't worry about it, but just be aware that if you have a "rod knock" someday, it might be the torque converter coming loose. On the other hand.....you can get to those bolts easily through the access cover. Your choice.

 

[Cranky]

Never had crank to flex plate bolts come loose even without Loc-tite.

 

[66 Sat]

Thanks fellas, I think I'll re-do the torque convertor bolts for peace of mind.
Cheers

 

[PRND21]

If the bolts move when you retorque them, you’re breaking the glue (Loctite), so to speak. If you go to the trouble of retorqueing them, I think I would take them out, clean them and use the red Loctite and retorque. I don’t think I’d worry about the crank bolts. Just my opinion.

 

[BeeKool]

I've had flexplate bolts come loose w/o loctite. Ive used the blue ever since

 

[wyrmrider]

locktite
4 Cyl
6 cyl
Harleys
so why not V8
I do not use single bolt cams after several disasters and lost races

 

[66Satellite47]

I now use red on flex to converter bolts(7x16"). Back in the day used Green, ("replaces welding and brazing") after blue came loose & ground up the cam bearing boss. Use red on the flex to crank bolts for insurance.

 

[wyrmrider]

There is a reason Mopar goes to more bolts on the racier engines
locktite helps for us without the special cranks
before locktie we used safety wire

 

[Brainemaster]

Hi, we recently re-installed the engine/transmission in my car and I've noticed my father-in-law used Permatex Low-Strength threadlocker (Purple) on the torque convertor to flexplate bolts, rather than the Medium (Blue) or High (Red). The bolts were all torqued to spec.
My question is has anyone had bolts come loose after using the low strength stuff? He would have also used it on the flexplate to engine bolts which is lot harder to fix than the torque convertor bolts. I realise now we should have used the blue (hence my question), but what does everyone reckon?

There is a reason Mopar goes to more bolts on the racier engines
locktite helps for us without the special cranks
before locktie we used safety wire

 

[Brainemaster]

The color means little. There is Red Locktight that is Medium and Blue Permatex that is medium. I suggest you use Medium regardless of the brand, torque to specification in across pattern and then rotate the final torque after.

 

[66 Sat]

Well they've been in for 3 years now with regular trips to 5,800 rpm and they haven't come loose yet, so I think they'll be fine...

 

[gtx6970]

I use red for just about everything.

same here

 

[Hubbarocks]

i have large bottle of blue, i put that S#!T on everything