|
Sponsored Links (Register now to hide all advertisements) |
|
|
Thread Tools | Display Modes |
05-07-2020, 11:42 AM | #1 |
Senior Member
Join Date: May 2013
Location: Pa.
Posts: 2,163
|
1 Fly wheel 2 PP thread bad
Hi guys, went to reinstall PP on flywheel & Murphy showed up on last bolt! Per 17-20’lb torque spec last bolt stripped thread in flywheel! I know all the options. 1 Different flywheel w/o prob. 2 Helicoil. 3 weld redrilled retap. Or my solution as I have a lathe I went to a 3/8”-16 tap/thread & drilled a concentric hole in the 3/8”-16 bolt to remove weight till same weight as 5/16-18 bolt using balance scale to achieve same weight so it should still be balanced. I don’t like Helicoils. Didn’t wanna heat up flywheel w weld! Don’t think I need new flywheel! So that’s what I did. Engine still out of car. Don’t beat me too much but what do u think of my solution?
__________________
Nomad |
05-07-2020, 12:00 PM | #2 |
Senior Member
Join Date: Jun 2014
Location: Williamsburg, VA
Posts: 1,627
|
Re: 1 Fly wheel 2 PP thread bad
Shade tree approach:
Line the stripped hole with a tube of tinfoil and put the original bolt in just tight enough that the lock washer is copressed so it will not come loose. The balance is preserved and the pressure plate could care less that it is fastened with five and a half bolts instead of six. Alternatively, fill the hole with JB Weld, drill it, tap it, and torque it to about half recommended value. |
Sponsored Links (Register now to hide all advertisements) |
|
05-07-2020, 12:04 PM | #3 |
Senior Member
Join Date: Dec 2013
Location: Minnesota, Florida Keys
Posts: 10,303
|
Re: 1 Fly wheel 2 PP thread bad
I am not enamored with any of the above approaches. I would use a quality thread insert (Keen-Sert, etc.) and be sure.
|
05-07-2020, 12:58 PM | #4 |
Senior Member
Join Date: May 2010
Location: Canada Where it snows
Posts: 2,058
|
Re: 1 Fly wheel 2 PP thread bad
Hope you don't fly,aircraft are one of the largest users you can find with heli coil approved repair scheme. On a side note welding cast iron and drilling and tapping will be another venture you should eliminate from your offerings.It becomes almost non machinable at best. "Tub" has also given sound advice
R |
05-07-2020, 02:16 PM | #5 |
Senior Member
Join Date: Jul 2014
Location: Iowa
Posts: 1,634
|
Re: 1 Fly wheel 2 PP thread bad
Try a metric threaded bolt. Sometimes it will grab damaged threads and allow careful tightening when the SAE threads are worn or cross threaded.
|
05-07-2020, 03:16 PM | #6 |
Senior Member
Join Date: Dec 2010
Location: North of sandy ago, CA.
Posts: 2,064
|
Re: 1 Fly wheel 2 PP thread bad
Sponsored Links (Register now to hide all advertisements)
Bruce
__________________
Works good Lasts long time |
05-07-2020, 04:29 PM | #7 |
Senior Member
Join Date: Dec 2013
Location: Minnesota, Florida Keys
Posts: 10,303
|
Re: 1 Fly wheel 2 PP thread bad
|
05-07-2020, 04:32 PM | #8 |
Senior Member
Join Date: Apr 2019
Location: Kansas
Posts: 920
|
Re: 1 Fly wheel 2 PP thread bad
I think your fix will work just fine. If your "new" bolt made torque and felt solid doing so, I don't see any reason to worry.
Terry
__________________
"It don't take but country smarts to solve the problem" (Smokey Yunick) '41 Merc Town Sedan / 260" 8CM engine '66 Fairlane four door / "warmed up" 302 |
05-07-2020, 06:18 PM | #9 |
Senior Member
Join Date: May 2013
Location: Pa.
Posts: 2,163
|
Re: 1 Fly wheel 2 PP thread bad
Thx all, I do agree welding cast & trying to reaching is a poor option. Keensert I agree is a good fix but don’t think significantly different than my fix which eliminates the extra piece of metal. No way on the drilling tapping a new pattern without a precision mill & turn table, have a horror story w a flywheel I had originally gotten w the vehicle that after several engine pulls & detective work realized it was .090 out of ci centricity causing major vibration due to out of balance condition! I did a test run & used another 3/8-16 bolt like the one I’m using in a junk flywheel I put same thread in & torqued to 30 ‘lbs w no problem. I will use the 3/8-16 bolt I modified to correct weight. 1 out of 5 of u agrees thx Terry, u & me makes 2 outa 5, that’s 40% LOL! Thx all for comments & not spanking me too hard! Being a machinist & having experience in dynamic balancing I believe it’ll b fine.
Best all A
__________________
Nomad |
05-07-2020, 06:37 PM | #10 |
Senior Member
Join Date: May 2010
Location: East Shore of LAKE HOUSTON
Posts: 11,106
|
Re: 1 Fly wheel 2 PP thread bad
It SEEMS pretty evident that some of y'all have never witnessed what's left after a clutch explosion. I remember two different occasions specifically back in the latter '60s, and it ain't nice! One guy lost a leg over it. That's one area that you couldn't make me cut ANY corners. You DO realize that those six bolts have specially-sized shoulders and lengths? Do yourself a huge favor and if you can't afford a new flywheel, at least round-up a good used one. At the very least do as suggested above and re-drill and tap (PRECISELY) at the 60 degree offset...…..did I say PRECISELY? And don't just go to Lowes and buy six grade 8 bolts.....get the proper, dedicated pressure plate bolts. But WTF do I know? DD
|
05-07-2020, 06:52 PM | #11 |
Senior Member
Join Date: May 2010
Posts: 2,173
|
Re: 1 Fly wheel 2 PP thread bad
C512>>>I think your fix will work just fine.>>>
AG>>>thx Terry, u & me makes 2 outa 5,>>> Ditto. Probably makes it at least 3 outta 6 oops 7 now. 8^) Jack E/NJ |
05-07-2020, 06:53 PM | #12 | |
Senior Member
Join Date: May 2010
Location: Wisconsin, USA
Posts: 8,990
|
Re: 1 Fly wheel 2 PP thread bad
Quote:
Scatter shield was installed soon thereafter.
__________________
"I can explain it for you. However, I can't understand it for you". |
|
05-07-2020, 06:54 PM | #13 |
Senior Member
Join Date: May 2010
Location: Wisconsin, USA
Posts: 8,990
|
Re: 1 Fly wheel 2 PP thread bad
A template? Really?
__________________
"I can explain it for you. However, I can't understand it for you". |
05-07-2020, 06:55 PM | #14 | |
Senior Member
Join Date: May 2010
Location: Wisconsin, USA
Posts: 8,990
|
Re: 1 Fly wheel 2 PP thread bad
Quote:
__________________
"I can explain it for you. However, I can't understand it for you". |
|
05-07-2020, 07:14 PM | #15 | |
Senior Member
Join Date: May 2010
Location: Schooley's Mountain
Posts: 530
|
Re: 1 Fly wheel 2 PP thread bad
Quote:
Ken |
|
05-07-2020, 07:18 PM | #16 |
Senior Member
Join Date: Dec 2013
Location: Minnesota, Florida Keys
Posts: 10,303
|
Re: 1 Fly wheel 2 PP thread bad
OK. You can make that 3 1/2 out of 9, because I think what the O/P suggested is the best of the bad ideas.
But it's still a bad idea. I used to drag race too. |
05-07-2020, 07:22 PM | #17 |
Senior Member
Join Date: May 2010
Location: Wisconsin, USA
Posts: 8,990
|
Re: 1 Fly wheel 2 PP thread bad
Ya know, this is yet another of those threads that perplexes me.
Man oh man, I pray some of you guys are never near me on the highway. Some guys should simply put the wrench down, shut the lights off and leave the garage...
__________________
"I can explain it for you. However, I can't understand it for you". |
05-07-2020, 08:32 PM | #18 |
Senior Member
Join Date: May 2013
Location: Pa.
Posts: 2,163
|
Re: 1 Fly wheel 2 PP thread bad
Wow! There’s the ass kicking I expected! While I still think my plan was viable considering the almost 20% larger hardware, I’ll go w a Helicoil fix staying w original 5/16-18 PP hardware. I asked for ur opinion so. As Ronnie indicated Helicoils r certified repair for threads in aircraft & aerospace industry so gotta b good for old fords
__________________
Nomad |
05-07-2020, 09:57 PM | #19 |
Senior Member
Join Date: Oct 2011
Location: Shelton, WA
Posts: 3,799
|
Re: 1 Fly wheel 2 PP thread bad
And as stated above, always use the correct shoulder bolts on the flywheels designed for them. Personally those flywheels are not difficult to obtain and are not rare. I would junk the flywheel with stripped hole and get another off the shelf.
|
05-08-2020, 01:11 AM | #20 | ||
Senior Member
Join Date: May 2010
Location: East Shore of LAKE HOUSTON
Posts: 11,106
|
Re: 1 Fly wheel 2 PP thread bad
Quote:
Now that's funny! Is a cardboard template good enough? I guess using the pressure plate itself would complicate matters? Quote:
Now there's a perfect example of some good ol' MSM-like obfuscation. What Ronnie "indicates" ain't necessarily the WHOLE story for ALL parts in flyin' flivvers and space ships. With your mind seemingly made-up, I'm not sure why you even wasted your time asking for advice here to begin with. Just try VERY hard to imagine the scary stuff going-on inside that clutch housing with that flywheel/clutch spinnin' at even 2,500 RPMs. THEN try to imagine the tremendous multi-directional forces and loads imposed on those six, lousy 5/16" bolts screwed-into Helicoils when ya raise the RPMs to four grand and enthusiastically engage the clutch! GOOD LUCK, ol' buddy! I wish ya the best!! Just remember what deuce_roadster indicated....used flywheels are NOT hard to round-up. DD |
||
|
|
Sponsored Links (Register now to hide all advertisements) |
|