Bolting TQ conv to BD flexplate

NevadaLLY

Adam B
Feb 24, 2019
311
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Reno, NV
I'm in the middle of the build and looking for advise on using the BD flexplate and a built trans by Mike L. During install, should I use RED or BLUE loctite? I've seen a bit of conflicting info. Yes, red should use heat to remove (I didn't use heat unbolting the converter taking out my trans installed by Mike) so either Mike didn't use red or I got lucky. I didn't see any thread damage to note. Thinking of that, I'm guessing blue but now not sure. :unsure:

Next - should I get new bolts or re-use? I don't think they are TTY and the OEM vs BD flexplate thickness isn't much difference. I haven't measured but the part is supposed to be directly interchangeable.

Finally, when re-installing the engine, what has been your best process to line up the trans/TQ/flexplate. Do I push the TQ converter back, bolt up the bell housing, then slide the TQ conv FWD to touch the flexplate and then bolt up?
 

Chevy1925

don't know sh!t about IFS
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Oct 21, 2009
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there are different types of "red" loctite. some with far more holding strength than others. the stuff mike uses isnt going to pull threads out and its not globbed all over the bolt. a little dab will do ya. Just use the standard red loctite or permitex, make sure threads are clean of old stuff and dab a little on the bottom of the threads.

re-use what came out of the converter, dont use factory bolts.

you dont need to push/pull the converter once the engine is back in and the bell housing is bolted up. get the fly wheel bolt hole lined up with the starter hole before dropping the engine in and once the bell housing is bolted down, you can use a flat head screw driver on the converter to spin it through the metal inspection port on the bottom of the bell housing. yes it will make little scratches on the converter but it wont hurt a thing. the converter should spin easily with no noises like its spinning against metal.
 

NevadaLLY

Adam B
Feb 24, 2019
311
39
28
Reno, NV
there are different types of "red" loctite. some with far more holding strength than others. the stuff mike uses isnt going to pull threads out and its not globbed all over the bolt. a little dab will do ya. Just use the standard red loctite or permitex, make sure threads are clean of old stuff and dab a little on the bottom of the threads.

re-use what came out of the converter, dont use factory bolts.

you dont need to push/pull the converter once the engine is back in and the bell housing is bolted up. get the fly wheel bolt hole lined up with the starter hole before dropping the engine in and once the bell housing is bolted down, you can use a flat head screw driver on the converter to spin it through the metal inspection port on the bottom of the bell housing. yes it will make little scratches on the converter but it wont hurt a thing. the converter should spin easily with no noises like its spinning against metal.
I'm planning to use Loctite 271. As far as I'm aware, the differences in the RED have to do with fastener size, high temp, etc. I don't think this requires either.

You say re-use what came out, but then not factory bolts. I never saw the converter bolts Mike pulled out, but assumed that's what went back in. Is this not the case? IF so, this will be the third time they're being torqued up.
 

Bdsankey

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Feb 1, 2018
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I'm planning to use Loctite 271. As far as I'm aware, the differences in the RED have to do with fastener size, high temp, etc. I don't think this requires either.

You say re-use what came out, but then not factory bolts. I never saw the converter bolts Mike pulled out, but assumed that's what went back in. Is this not the case? IF so, this will be the third time they're being torqued up.

If you have an aftermarket converter in your trans then you DO NOT have OEM bolts. Like James said, I wouldn't be scared to reuse them. You're not making enough power where I'd be worried about compromising the bolt plus with the way we have to tighten converter bolts you won't even get close to proof load of a M10 fastener.
 

JoshH

Daggum farm truck
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Feb 14, 2007
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If you have an aftermarket converter in your trans then you DO NOT have OEM bolts.
That is the case as long as he has a triple disc which I'm sure he does. I just don't want someone reading this in the future with a single disc billet thinking their converter is ruined if someone used stock converter bolts.
 

Bdsankey

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That is the case as long as he has a triple disc which I'm sure he does. I just don't want someone reading this in the future with a single disc billet thinking their converter is ruined if someone used stock converter bolts.


Touche. A blanket statement would be to use the bolts that were supplied with the converter/removed from that specific converter. If you are uncertain, contact the converter manufacturer.
 

NevadaLLY

Adam B
Feb 24, 2019
311
39
28
Reno, NV
Thanks guys - to confirm, it is a triple disk. I just wasn't sure with the fasteners as I never saw what was originally installed.
 

sneaky98gt

Member
Nov 5, 2013
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As for the Loctite: just because they came out without heat, doesn't mean that red wasn't used. I've used red of all varieties on hundreds of applications, and have never had to use heat to remove unless they were small (< 10-32 or M5), especially if you can get some good leverage on it. Now retaining compound on the other hand (the green stuff usually), that's a whole 'nother story....only use that stuff to assemble things (not screws) if you NEVER want it to come back apart.

I'm no expert on converter bolts, but just generally speaking considering the application, I'd use red if it calls for anything to be used at all. Anything less (blue mostly) isn't really going to do anything on bolts that big, as tight as they are supposed to be.