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9/17/2018 11:18 PM  #1


FLEX PLATE BOLT SIZE....

I am installing the motor/tranny (rebuilt, stock 289 & c4) in my wife's 1965 mustang.  I cannot find the flex plate to crankshaft bolts!  I searched online for a set of 6.  Does anyone know the proper length and if they are full-thread, i.e. no shoulder?  Online photos/descriptions provided by suppliers show various combinations of 0.6" to 1" long, part shoulder, no shoulder, taller hex cap (like a normal hex cap bolt), shorter hex cap, etc.  Just when I find what I think is the correct set, they are named "flywheel" bolts.  To my knowledge, flex plate bolts are not interchangeable.  Flywheel bolts will have a shoulder due to the flywheel thickness.
I know they are 7/16" 20 pitch.  The crank holes will accept a 1" long bolt, for both flex plates and flywheels.  I am 99% confident the cap is short and full thread, like most flex plate bolts.  But I cannot find a supplier that shows this in the description!
We have two weeks to pack up, as we sold our house.  Time is very critical; I can't afford a trial and error process.  Your input is appreciated.  Thank you.
Now, if I can find the 4th flange nut for flex plate to converter.....ugh!!!  I hate moving.


Parkinson's, it's not just for old folks
 

9/18/2018 4:31 AM  #2


Re: FLEX PLATE BOLT SIZE....

They're full thread for sure, at least the stock ones are.  1" sounds right.  0.6" is not even 5/8" long; that's too short.
 

 

9/18/2018 9:05 AM  #3


 

9/18/2018 10:18 AM  #4


Re: FLEX PLATE BOLT SIZE....

5/8” for automatic
1” for manual

Full threads, since the flexplate is quite thin.
Usually a short head height is used.

Be sure to use thread sealer or the threads will leak oil.  The bolts on a 289/302 go all the way through the crank flange.


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
 

9/18/2018 10:21 AM  #5


Re: FLEX PLATE BOLT SIZE....

MS,
What type of thread sealer do you recommend for this?
I have used Blue Loc-tite for this in the past, but always wondered if I should be using something else.

 

9/18/2018 3:38 PM  #6


Re: FLEX PLATE BOLT SIZE....

I've always just put a dab of silicone on them. 

 

9/18/2018 7:32 PM  #7


Re: FLEX PLATE BOLT SIZE....

Clean bolts and holes thoroughly. I use Ultra RTV.  Place the sealer (whatever you use) on the BOLT THREADS ONLY, NOT IN THE CRANK.  That way the bolt does not push a glob of sealer into the engine.


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
 

9/19/2018 7:26 AM  #8


Re: FLEX PLATE BOLT SIZE....

Thank you both.

 

9/20/2018 4:05 PM  #9


Re: FLEX PLATE BOLT SIZE....

Apparently either works fine.  I took a 5,0 apart from a 2001 Explorer with automatic and it had 1" bolts from the factory.


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
 

9/20/2018 5:57 PM  #10


Re: FLEX PLATE BOLT SIZE....

Thanks for all the replies.
I could only find 5/8” full thread. I used those along with red thread lock.
We installed the motor and tranny.  Now moving on to making it go VROOOOOM...

Word to the wise, if your son’s senior high project is to R & R mom’s worn out 289 while you put a new front end under it, don’t put your house for sale.  We sold our home in 27 hours!  Now we have parts and the car stored at various locations....where did that crank pulley go?....


Parkinson's, it's not just for old folks
     Thread Starter
 

9/20/2018 6:49 PM  #11


Re: FLEX PLATE BOLT SIZE....

Just curious.....what is your location?! That's a quick sale....must be NW or  Charleston,SC.!
 


Get busy Liv'in or get busy Die'n....Host of the 2020 Bash at the Beach/The only Bash that got cancelled  )8
 

9/21/2018 9:20 AM  #12


Re: FLEX PLATE BOLT SIZE....

NW...Idaho.  Now we are Florida bound?


Parkinson's, it's not just for old folks
     Thread Starter
 

9/21/2018 3:10 PM  #13


Re: FLEX PLATE BOLT SIZE....

Good............Housing prices are a little more stable in Fla. (I think)
You're really gonna love the change in climate
  NO MORE......"oh its hot....butt it's a dry heat"!
OMG!!....Flar-dee n the summer....You can actually SEE the air you are trying to breath(humidity X 10!)
Butt at least you will be surrounded by "good-old-boyz" (and tourists)....Really are some good folks in the sunshine state.
To make it car related....Can drive your Mustang year round!
                                        Dis-connect/remove your aggravating choke
                                        Stupid auto inspection are now just a bad dream
                                        One gallon of anti freeze is enough for ALL your vehicles
                                        "Snow tarzes?".....What dem is?
                                        Even stainless steel will rust!
Welcome to the south Brother!!!
6sally6

Last edited by 6sally6 (9/21/2018 3:11 PM)


Get busy Liv'in or get busy Die'n....Host of the 2020 Bash at the Beach/The only Bash that got cancelled  )8
 

9/22/2018 9:14 AM  #14


Re: FLEX PLATE BOLT SIZE....

We can’t wait! The dry, 100 degree plus, heat here is absolutely terrible. And the cold, snowy winters are too long.
I’ve been here my entire life. We are ready for a change, for sure!
Snow tarzes, now that’s funny! Florida, here we come


Parkinson's, it's not just for old folks
     Thread Starter
 

Board footera


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