Flywheel Loosened - 250

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Flywheel Loosened twice - 250 engine with T5 in 61 Comet. SBF BH with T5 adapter. 157T Neutral balance SFI Flywheel - Centerforce clutch.

Shortly after swapping a tranny few years back, the clutch felt odd and noisy. Removed to find ARP fasteners slightly loose and flywheel slightly loose. I thought I had a brain-fart when torqueing FW bolts . I re-applied red Loctite and torqued safely with no further problem.

Last year I replaced T5 with upgrade' drove it a few hundred miles since. Yesterday I pulled tranny after obvious rattle noise and - Flywheel was loose again. Sure I followed ARP / Loctite reccomends' .

Ordered a replacement Flywheel and new fasteners but am concerned with situation and will accept opinions ( 8) ) on FW's, fasteners and possible faults ...





thanks

stay safe
 
Check the ARP bolts to make sure they are for a flywheel and not an automatic flexlate.
Flywheel bolts are longer; the shorter bolts for the flexplate won't adequately secure the flywheel.

That's my WAG.
 
never re-use FW bolts. Don't they stretch w/each application? and
should B replaced each time? That's my understanding. I do this
w/bolts in other apps as well. May B I'm over cautious...
¯\_(ツ)_/¯
hate spendin 'extra $', school me !
 
thanks for reply

Two lengths listed for Ford FW's are 1" below head of FW fastener or .9" below head. Bore depth on 250 crank seems to accommodate either.

(ARP fasteners had been replaced when FW loosened)

'Suspicious of the FW (from an E-Bay supplier) . Although SFI rated, seemed a little rough on FW/Crank surface.

Ordered a "Speedmaster" SFI FW from my usual performance parts vendor.
 
isn't there some sorta different champher on the shoulder of the bolt (& FW? I'm recalling something there too.)
¯\_(ツ)_/¯
Let us (me) know how U do...
Thnx
 
CORRECTION

WRONG:
BTW : Crankshaft FW threads do not go through to Crankcase and do not require sealant.

CORRECTED:
FW fastener thread bores of Crank DO pass through to crankcase. Loctite on threads should be sufficient AFAIK.
 
Followup on FW fasteners:

ARP on Left - OEM on Right:

ARP appear to be full 1", OEM slightly less (.9" ?). OEM bolt has recess at base of threads vs ARP profile.

..

Isolated in my garage with way too many projects ...
 
Ordered a new FW, Fasteners and new Red Loctite. No fooling around with @ 30lbs billet steel at 5,000 RPM.






thanks
 
Hi, that is not something I would ever want to see.
We always use the old flywheel bolts, with red loctite, and torque them down.
Even on my friends Saturday night stock car. 7000 RPM.
So how does the hole in the flywheel register on the crank? It should be a nice snug fit.
Good luck
 
The 250's are more vibration prone than the 200's, maybe you should take it apart sooner to check for these bolts loosening up. Otherwise I think your current procedure using the ARP bolts and Red Locktite is excellent. What part number are the ARP flywheel bolts? I don't think those are Ford OEM Flywheel bolts on the right they need to have the shoulder under the bolt head to fit into a Ford flywheel correctly, they just look like a standard bolt to me. Good luck. (y) :nod:
 
In my mind, you did the ARP bolts twice and they became loose twice. I'd go with the stock bolts atp.

As Bubba keenly pointed out, that bolt you have there differs from the oem bolt. I dug out one of the oem bolts that was on my 250's flywheel and it is about 1 1/16" long, has a shoulder and has the groove around the base of the shoulder on the faying side of the bolt head.

AfLpqQ.jpg
 
... so much info about six bolts that make the car go.

The fastener pics are from my all original 1974 35K mile 250 Maverick OEM FW and clutch. OEM Ford clutch and FW removed to install a SFI rated FW with Centerforce clutch.

. .

New bolts ordered are standard Dorman OEM replacement FW bolts instead of the ARP listed by vendors (possible wrong application?) , waiting to see - 'have those OEM's...

have fun
stay safe
 
High performance six's have flywheel bolts loosening problems even with oem bolts.
Use pematex surface cleaner activator and clean threads crank flange flywheel and bolts...You want everything squeaky clean ..
I smear some 271 red lightly on crank and pilot of the flywheel and lube up the bolts with 271red ...Arp wants ultra lube under the head,and thread locker on the threads, probably to get the right stretch with their bolt.. Not sure about that.
Check your torque wrench and torque to bolt mfg. specs.
Make sure that you test the ''new ''locker on some test parts first, even ''new'' can be bad.. Trust me on that.
Is your Fisher damper on this engine ?
 
Thanks for the step by step for confidence. Waiting on parts and reviewing the problem I'm focusing on the 'Cat" brand SFI FW that loosened and the Centerforce clutch with the clamping weights as causing or contributing to fault. The FW had a machining blemish on the crank mating surface and the Clutch weights may affect balance (?) . Glad that no permanent crank flange damage seems to be indicated.

. .



have (safe) fun


Yes , the 'Fisher" damper is on this 250.



...if you are interested, I recently found this contact in my tech notes . I had called them back in 2008 and was told they built them for Jack Clifford in the 80's and 'may still have a few around somewhere"

(2008 notes) Fisher Dampeners and Automotive Balancing-South Gate, CA (562) 861-6882.
 
Thanks for the info,
Had Fisher make one for my new build 200 ...I do not think that the balancer is a problem, but they do need to be serviced occasionally, there is moving parts...It would not hurt to try a different clutch ..I know nothing about centerforce, but it looks odd.

Let's hope that it is bad, weak, loc tight.
 
I have a 250 with vibration about 55 mph and up that makes the car undriveable. I thought it was ujoints. Nope. vibration is rpm related even in neutral. Is there any way to check flywheel without pulling bell ? Throwout bearing noisy. Beginning to suspect clutch or pressure plate assembly
 
Hi, you can start your own chats, no need to tag on to an old one. How long has the vibration been going on? I would remove the fan belt(s) and see if the vibration goes away. There is a chance the clutch or pressure plate is coming apart and is now out of balance. Sometimes a bad throw out bearing feels and sounds different as you press on the clutch. You can't inspect the clutch assembly until you remove the bell housing. Good luck
 
“...no need to tag on to..."
In Fact More eyes ona New, self generated thread
 
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