The Ford Barn

jrvariel48 · 09-13-2020, 08:53 AM

So this is the second time my crank pulley bolt came loose and disappeared onto the road. The first time it happened, I just figured I didn't tighten it enough. I installed a new bolt, torqued it to 50lbs. with red lock-tite and it came off this morning. This is a blower motor so the crank bolt and pulley are not stock, but I'm not sure if that has anything to do with it.
Looking for an explanation.
Thanks Joe

Lawson Cox · 09-13-2020, 08:58 AM

Gremlins,

39portlander · 09-13-2020, 09:26 AM

Joe could you drill the shank and use a castle nut, You got me curious.

Get one of those remote cameras and possibly video that area by the pulley and see what is going on while driving, good luck and let us know how you make out.

19Fordy · 09-13-2020, 10:03 AM

Are you torquing bolt to specs? Are the threads worn? Is there any type of lock washer or "spring washer" you could use with the bolt.

Here's a very good link to washers that might solve your problem. Lots of great information.
https://www.google.com/search?q=spec...hrome&ie=UTF-8

Read this:
https://vention.io/blogs/best-anti-v...-fasteners-178

Read about "Smart Bolts".
http://www.smartbolts.com/insights/l...nt%20loosening.

First thing I would do is try a brand new Grade 8 bolt.
What engine is in your car?

jrvariel48 · 09-13-2020, 10:20 AM

Quote:

Originally Posted by 19Fordy

Are you torquing bolt to specs? Are the threads worn? Is there any type of lock washer or "spring washer" you could use with the bolt.

Here's a very good link to washers that might solve your problem. Lots of great information.
https://www.google.com/search?q=spec...hrome&ie=UTF-8

Read this:
https://vention.io/blogs/best-anti-v...-fasteners-178

Read about "Smart Bolts".
http://www.smartbolts.com/insights/l...nt%20loosening.

First thing I would do is try a brand new Grade 8 bolt.
What engine is in your car?

Lotsa great reading Fordy! The crank is new as was the bolt. I'm looking into the Nord-lock washer system. They seem to hold up to just about any situation.
I was using grade 8 bolts, but no lock washer, just some red lock-tite.
Engine is a blown 1950 8BA.
Thanks Joe

jrvariel48 · 09-13-2020, 10:23 AM

Sponsored Links (Register now to hide all advertisements)

Quote:

Originally Posted by 39portlander

Joe could you drill the shank and use a castle nut, You got me curious.

Get one of those remote cameras and possibly video that area by the pulley and see what is going on while driving, good luck and let us know how you make out.

Not sure if I could drill the shank, but the camera's a great idea. I use three of them on board to record A/F reading, fuel pressure, vacuum and rpm when tuning.
Thanks!
Joe

jrvariel48 · 09-13-2020, 10:24 AM

Quote:

Originally Posted by Lawson Cox

Gremlins,

I hate Gremlins!!! Lol

Ronnie · 09-13-2020, 10:40 AM

I would speak with Loctite on their 800 number and get it from the people that know. The red is basically bomb proof.

R

earlyride · 09-13-2020, 10:46 AM

Just a thought, how tight is the hub and pulley onto the crank? with the added load of the blower and if it's not a tight enough fit it might cause some wobbling and loosening of the bolt that holds it in place.

jimvette59 · 09-13-2020, 10:55 AM

Lets see some pictures of the crank pulley with out the bolt and spring washer.

deuce_roadster · 09-13-2020, 10:58 AM

I was thinking the same as earlyride, and perhaps the 2 surfaces (crank side and bolt side) of the pulley are not exactly 90 degrees from the centerline which would permit a wobble.
Also, did you clean the internal threads of the crank with Brakecleen or lacquer thinner and blow it out before using the locktite?

Ronnieroadster · 09-13-2020, 11:12 AM

Joe in the past when I have experienced the exact same issue as yours even with the blower belt helping the dampening. The problem was due to a balance issue which turned out to be the flywheel area. Even red locktite would not help. I would suggest try green locktite its a lot stronger than red if the bolt still comes loose after going to green then checking the bolt regularly to be sure its tight would at least keep the bolt in place and not on the road someplace.
Ronnieroadster

GOSFAST · 09-13-2020, 11:25 AM

Hi Joe, appears to be not enough torque on the bolt, this will cause your problem. If it doesn't get enough torque it will eventually work its way out!

What happens is having the correct "tension" on the bolt keeps it in place!

To add to the problem, the OEM dampers are NOT a press fit to begin with, this makes the torque number even more important.

Thanks, Gary in N.Y.

P.S. It's a bit ironic but Pontiac builds share the same characteristics, the OEM damper has always been a "slip-fit", getting the damper bolt up to torque does take a bit of doing! I don't have the OEM torque handy for the Flathead but the Pontiacs must get a minimum of 150# (160# preferred) to do the job! Same size bolt/washer as the Flatheads, being 5/8-18 x 1.750" I believe?

JSeery · 09-13-2020, 11:36 AM

The torque specifications on a grade 8 5/8-18 bolt is 240 ft-lbs dry and 180 ft-lbs lubed. So 50 is not even close. 50 ft-lbs is in the range of a 3/8 inch bolt.

Zeke3 · 09-13-2020, 11:38 AM

It sounds like the torque you are using is too low. If the bolt is a 5/8"-18 and a grade 8 capscrew, the torque should be in the 235 lb-ft range, reference Craftsman generic torque table.

There is a lot of torsional vibration going through that joint to the crank pulleys. Increasing the grip length of the bolt will get more stretch in the bolt and resistance to loosening. You can increase the length by adding a thick wall spacer.

I do not recommend using a lock washer, it is just another spring in the system.

jrvariel48 · 09-13-2020, 12:20 PM

Quote:

Originally Posted by Ronnie

I would speak with Loctite on their 800 number and get it from the people that know. The red is basically bomb proof.

R

Great suggestion Ronnie, thank you

jrvariel48 · 09-13-2020, 12:22 PM

Quote:

Originally Posted by earlyride

Just a thought, how tight is the hub and pulley onto the crank? with the added load of the blower and if it's not a tight enough fit it might cause some wobbling and loosening of the bolt that holds it in place.

It's a pretty snug fit as I remember it. I can pull the belts and check to see if my memory serves me right!

jrvariel48 · 09-13-2020, 12:23 PM

Quote:

Originally Posted by jimvette59

Lets see some pictures of the crank pulley with out the bolt and spring washer.

OK I'll get some pics in a bit. Thanks

Mart · 09-13-2020, 12:23 PM

A steel bolt in a steel nut of suitable grade of steel will achieve the numbers quoted above, but as it is being screwed into a cast iron crank snout would a lower value be more appropriate? I am thinking 50 lbs sounds a bit low, though.

Mart.

jrvariel48 · 09-13-2020, 12:24 PM

Quote:

Originally Posted by deuce_roadster

I was thinking the same as earlyride, and perhaps the 2 surfaces (crank side and bolt side) of the pulley are not exactly 90 degrees from the centerline which would permit a wobble.
Also, did you clean the internal threads of the crank with Brakecleen or lacquer thinner and blow it out before using the locktite?

I did clean everything with brake clean and a bore brush. Also used bore style Qtips until there was no dirt. Thanks deuce

jrvariel48 · 09-13-2020, 12:26 PM

Quote:

Originally Posted by Ronnieroadster

Joe in the past when I have experienced the exact same issue as yours even with the blower belt helping the dampening. The problem was due to a balance issue which turned out to be the flywheel area. Even red locktite would not help. I would suggest try green locktite its a lot stronger than red if the bolt still comes loose after going to green then checking the bolt regularly to be sure its tight would at least keep the bolt in place and not on the road someplace.
Ronnieroadster

Great advice as usual Ron, thank you

jrvariel48 · 09-13-2020, 12:32 PM

Quote:

Originally Posted by GOSFAST

Hi Joe, appears to be not enough torque on the bolt, this will cause your problem. If it doesn't get enough torque it will eventually work its way out!

What happens is having the correct "tension" on the bolt keeps it in place!

To add to the problem, the OEM dampers are NOT a press fit to begin with, this makes the torque number even more important.

Thanks, Gary in N.Y.

P.S. It's a bit ironic but Pontiac builds share the same characteristics, the OEM damper has always been a "slip-fit", getting the damper bolt up to torque does take a bit of doing! I don't have the OEM torque handy for the Flathead but the Pontiacs must get a minimum of 150# (160# preferred) to do the job! Same size bolt/washer as the Flatheads, being 5/8-18 x 1.750" I believe?

To Gary and others about the torque.
I was just going by the torque values I found here on the barn.
I'm using grade 8 bolts so I can definitely crank it down. I think I'd like to try the Nord-Lock style washers, I don't think it could hurt for the $2.50 the set costs.

It would be great if we could all agree on a torque value!!
Anyone??!!
Thanks, Joe

jrvariel48 · 09-13-2020, 01:01 PM

Could there be a problem with the space between the pulley face and crank face? It's about a 3/16" recess.

glennpm · 09-13-2020, 02:18 PM

I think you should look at the run-out of the pulley, i.e the amount between minimum and maximum at a point on the pulley.

I'd pull the plugs and try to get a helper; or turn crank bolt manually as you watch; or make a starter switch to bump it (ignition off).

If this static view isn't conclusive, I'd run it motor running through different RPMs with a helper and watch to see if you have dynamics of the pulley and/or crank snout vibrating from bending forces.

cadillac512 · 09-13-2020, 02:32 PM

I don't think the distance from front of hub to end of crank is a problem as long as it's sitting properly on the machined register of the pulley and crank.

Your washer is THICK, right? Like 3/8" or so?

Joe Abbin recommends 130-145# of torque on the crank bolt, and that sounds about right.

Terry

19Fordy · 09-13-2020, 03:35 PM

Sponsored Links (Register now to hide all advertisements)

I just went and checked the bolt head size of the crank pulley bolt holding the crank pulley to my 8BA crankshaft. The head size is 7/8 in. I am using 8RT water pumps and the pressed steel 49 Merc wide belt crank pulley

The 5/8 size mentioned by others in this thread seems to small to me.
Could it be a misprint? Look at what the 49-51 Merc repair manual says below..

FYI: In the 1949-51 Mercury Manual, on page 72 of Volume 1 it shows the crank pulley to crankshaft bolt to be 5/8-18 x 1 1/8 long and that it's tightened to 130 to 135 foot pounds for the 1949 and 1950 Merc and 45 to 55 foot pounds for the 1951 Merc. only.

Clarification of this issue would be appreciated.

Ronnieroadster · 09-13-2020, 06:22 PM

Joe the washer under your bolt should sit on the inner lower surface of the hub assembly not on the face of the outer pulley which is a higher surface. The washer should be thick as mentioned above at least 3/8 inch and as large a diameter possible when sitting into that recess. As to the idea the torque needs to be extremely high heck the stock Flathead washer and bolt would never set at such high torque numbers the washer is to thin the bolt is mild steel and the thread is in a casting. Toque at 65 foot pounds is plenty thats all i ever use {on street engines and all out very fast engines} when the washer is thick enough and large enough in diameter to hold the pressure.
Ronnieroadster

JSeery · 09-13-2020, 06:49 PM

Quote:

Originally Posted by Ronnieroadster

Toque at 65 foot pounds is plenty thats all i ever use {on street engines and all out very fast engines} when the washer is thick enough and large enough in diameter to hold the pressure.
Ronnieroadster

65 may work fine, but all of the Ford spec's I'm seeing are around 130-140.

Mart · 09-14-2020, 03:03 AM

Here's an idea. As you have bolts nearby, why not make a plate with a hex hole in the middle that drops over the bolt head and then has the other bolts going through it to lock it in place? Or some other sort of tab washer type device, or even some locking wire attached to an adjacent bolt.
That said, a good bolt, a decent washer (turned up in a lathe as a custom job) and a spring washer ought to be all that is required.
Just thinking out loud.

Mart.

jimvette59 · 09-14-2020, 08:30 AM

Zeke3 the pulley is longer then the end of the crankshaft.

GOSFAST · 09-14-2020, 09:41 AM

Quote:

Originally Posted by jrvariel48

Could there be a problem with the space between the pulley face and crank face? It's about a 3/16" recess.

Hi Joe, can you measure that pulley opening across? It appears (from the photo) the factory washer will not fit that particular setup?

The OEM Flathead washer measures .312" (thick) x 1.560" (O.D.) x .660" (hole size).

The Pontiac washer measures .310" (thick) x 1.625" (O.D.) x .655" (hole size).

The OEM (8BA) Flathead bolt measures 1.625" (O/A length) x 1.150" (UHL threaded) x .875" hex nut (.470" thick).

The Pontiac bolt measures 2.000" (O/A length) x 1.600" (UHL threaded) x .937" hex nut (.400" thick).

Thanks, Gary in N.Y.

P.S. I know there's different opinions above on the torque for these size bolts but I definitely would want to at least be in the right neighborhood! For instance, if you back the torque way down your wheel lugnuts who do you blame when your wheels "fall-off"?? (More or less kidding here, maybe)

Zeke3 · 09-14-2020, 10:10 AM

The picture shows the crank nose, and inner hub and the accessory pulley. I assume the slot in the inner hub is for the keyway and the inner hub is installed such that it is pressing on the oil slinger and crankshaft gear.

I would fill most of the gap between the nose of the crankshaft and the inner hub with a spacer, leaving the inner hub slightly higher than the spacer. Then use a thick washer, no larger than the outside diameter of the inner hub so it does not press on the accessory pulley, as Ronnie suggested. Also, a grade 5 capscrew will be perfectly adequate at 65 ft-lb torque.

If that thing still falls out, I would safety wire it to one of the other bolts on the accessory pulley.

jrvariel48 · 09-14-2020, 04:18 PM

So I'm having my machinist make me a 3/8" thick washer at the proper diameter (1.750 OD) with a grade 8 bolt and the Nord-Lock system. I'll torque to 65-70 lbs and check it everytime I go for a ride. I also like the thought of tie wire and will do that if I find it loose again.

I appreciate all the input and will post the results!
Thanks again to everyone!
Joe

glennpm · 09-14-2020, 04:23 PM

That will be a good bolt up. Do yourself a favor and drill the bolt for safety wire now. If you find it’s getting loose, tighten it up and wire it.

Glenn

Hal Beatty · 09-14-2020, 04:58 PM

And I would have to agree with the safety wire suggestions. .041 diameter SS wire will hold a lot if it's properly installed.

jrvariel48 · 09-15-2020, 03:29 AM

Looking at the pulley, I have three button head screws that I'll have to change to hex head to drill them for the safety wire.
I'll wire from crank bolt to one of the three bolts. Should I wire the remaining two bolts together?

glennpm · 09-15-2020, 05:58 AM

It would be a good idea. If you don't want to use hex head bolts, maybe limited wrench clearance, use Allen head and drill those.

Glenn

Tony, NY · 09-15-2020, 01:23 PM

I would also use regular socket screws (drilled). Some info on button head screws: "Button head screws, set screws, and studs cannot be torqued like ordinary screws. These screws have a small contact area where the tool is applied compared to other kinds of head types (e.g. hex, socket, cap, Torx, etc.) Torque on these screws must be reduced. If this is not done, either the screw, the piece being fastened, or the tool will be damaged."

09-13-2020, 08:53 AM	#1
jrvariel48 Senior Member Join Date: Jan 2012 Location: New Jersey Posts: 1,425	Crank pulley bolt...Lost again!! So this is the second time my crank pulley bolt came loose and disappeared onto the road. The first time it happened, I just figured I didn't tighten it enough. I installed a new bolt, torqued it to 50lbs. with red lock-tite and it came off this morning. This is a blower motor so the crank bolt and pulley are not stock, but I'm not sure if that has anything to do with it. Looking for an explanation. Thanks Joe

09-13-2020, 08:58 AM	#2
Lawson Cox Senior Member Join Date: May 2010 Location: Above the gnat line in Georgia Posts: 7,009	Re: Crank pulley bolt...Lost again!! Gremlins, __________________ Life is like a roll of toilet paper. The closer to the end, the faster it goes. It is better to be seen, than viewed. "We sleep safe in our beds because rough men stand ready in the night to visit violence on those who would do us harm".

09-13-2020, 09:26 AM	#3
39portlander Senior Member Join Date: May 2010 Location: Suth'N Maine Posts: 1,996	Re: Crank pulley bolt...Lost again!! Joe could you drill the shank and use a castle nut, You got me curious. Get one of those remote cameras and possibly video that area by the pulley and see what is going on while driving, good luck and let us know how you make out.

09-13-2020, 10:03 AM	#4
19Fordy Senior Member Join Date: May 2010 Location: Coral Springs FL Posts: 10,942	Re: Crank pulley bolt...Lost again!! Are you torquing bolt to specs? Are the threads worn? Is there any type of lock washer or "spring washer" you could use with the bolt. Here's a very good link to washers that might solve your problem. Lots of great information. https://www.google.com/search?q=spec...hrome&ie=UTF-8 Read this: https://vention.io/blogs/best-anti-v...-fasteners-178 Read about "Smart Bolts". http://www.smartbolts.com/insights/l...nt%20loosening. First thing I would do is try a brand new Grade 8 bolt. What engine is in your car? Last edited by 19Fordy; 09-13-2020 at 10:09 AM.

09-13-2020, 10:40 AM	#8
Ronnie Senior Member Join Date: May 2010 Location: Canada Where it snows Posts: 2,058	Re: Crank pulley bolt...Lost again!! I would speak with Loctite on their 800 number and get it from the people that know. The red is basically bomb proof. R

09-13-2020, 10:46 AM	#9
earlyride Senior Member Join Date: May 2010 Location: Petaluma, cal. Posts: 132	Re: Crank pulley bolt...Lost again!! Just a thought, how tight is the hub and pulley onto the crank? with the added load of the blower and if it's not a tight enough fit it might cause some wobbling and loosening of the bolt that holds it in place.

09-13-2020, 10:55 AM	#10
jimvette59 Senior Member Join Date: Jun 2010 Location: Perry OH Posts: 1,330	Re: Crank pulley bolt...Lost again!! Lets see some pictures of the crank pulley with out the bolt and spring washer.

09-13-2020, 10:58 AM	#11
deuce_roadster Senior Member Join Date: Oct 2011 Location: Shelton, WA Posts: 3,800	Re: Crank pulley bolt...Lost again!! I was thinking the same as earlyride, and perhaps the 2 surfaces (crank side and bolt side) of the pulley are not exactly 90 degrees from the centerline which would permit a wobble. Also, did you clean the internal threads of the crank with Brakecleen or lacquer thinner and blow it out before using the locktite?

09-13-2020, 11:12 AM	#12
Ronnieroadster Senior Member Join Date: Dec 2010 Location: East Coast in CT Posts: 1,529	Re: Crank pulley bolt...Lost again!! Joe in the past when I have experienced the exact same issue as yours even with the blower belt helping the dampening. The problem was due to a balance issue which turned out to be the flywheel area. Even red locktite would not help. I would suggest try green locktite its a lot stronger than red if the bolt still comes loose after going to green then checking the bolt regularly to be sure its tight would at least keep the bolt in place and not on the road someplace. Ronnieroadster __________________ I use the F word a lot no not that word these words Flathead , Focus and Finish. "Life Member of the Bonneville 200 MPH Club using a Ford Flathead block" Owner , Builder, Driver of the First Ford Flathead bodied roadster to run 200 MPH Record July 13, 2018 LTA timing association 200.921 in one and a half miles burning gasoline. First ever gas burning Ford flathead powered roadster to run 200 MPH at Bonneville Salt Flats setting the record August 7th 2021 at 205.744 MPH

09-13-2020, 11:38 AM	#15
Zeke3 Senior Member Join Date: Dec 2014 Location: Columbus, IN Posts: 1,407	Re: Crank pulley bolt...Lost again!! It sounds like the torque you are using is too low. If the bolt is a 5/8"-18 and a grade 8 capscrew, the torque should be in the 235 lb-ft range, reference Craftsman generic torque table. There is a lot of torsional vibration going through that joint to the crank pulleys. Increasing the grip length of the bolt will get more stretch in the bolt and resistance to loosening. You can increase the length by adding a thick wall spacer. I do not recommend using a lock washer, it is just another spring in the system.

09-13-2020, 12:23 PM	#19
Mart Senior Member Join Date: May 2010 Location: Solihull, England. Posts: 8,750	Re: Crank pulley bolt...Lost again!! A steel bolt in a steel nut of suitable grade of steel will achieve the numbers quoted above, but as it is being screwed into a cast iron crank snout would a lower value be more appropriate? I am thinking 50 lbs sounds a bit low, though. Mart.

09-13-2020, 02:18 PM	#24
glennpm Senior Member Join Date: Sep 2014 Location: Wiscasset, Maine Posts: 1,981	Re: Crank pulley bolt...Lost again!! I think you should look at the run-out of the pulley, i.e the amount between minimum and maximum at a point on the pulley. I'd pull the plugs and try to get a helper; or turn crank bolt manually as you watch; or make a starter switch to bump it (ignition off). If this static view isn't conclusive, I'd run it motor running through different RPMs with a helper and watch to see if you have dynamics of the pulley and/or crank snout vibrating from bending forces. Last edited by glennpm; 09-13-2020 at 02:34 PM. Reason: add dynamic test

09-13-2020, 02:32 PM	#25
cadillac512 Senior Member Join Date: Apr 2019 Location: Kansas Posts: 921	Re: Crank pulley bolt...Lost again!! I don't think the distance from front of hub to end of crank is a problem as long as it's sitting properly on the machined register of the pulley and crank. Your washer is THICK, right? Like 3/8" or so? Joe Abbin recommends 130-145# of torque on the crank bolt, and that sounds about right. 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

09-13-2020, 03:35 PM	#26
19Fordy Senior Member Join Date: May 2010 Location: Coral Springs FL Posts: 10,942	Re: Crank pulley bolt...Lost again!! Sponsored Links (Register now to hide all advertisements) I just went and checked the bolt head size of the crank pulley bolt holding the crank pulley to my 8BA crankshaft. The head size is 7/8 in. I am using 8RT water pumps and the pressed steel 49 Merc wide belt crank pulley The 5/8 size mentioned by others in this thread seems to small to me. Could it be a misprint? Look at what the 49-51 Merc repair manual says below.. FYI: In the 1949-51 Mercury Manual, on page 72 of Volume 1 it shows the crank pulley to crankshaft bolt to be 5/8-18 x 1 1/8 long and that it's tightened to 130 to 135 foot pounds for the 1949 and 1950 Merc and 45 to 55 foot pounds for the 1951 Merc. only. Clarification of this issue would be appreciated. Last edited by 19Fordy; 09-13-2020 at 08:18 PM.

09-13-2020, 06:22 PM	#27
Ronnieroadster Senior Member Join Date: Dec 2010 Location: East Coast in CT Posts: 1,529	Re: Crank pulley bolt...Lost again!! Joe the washer under your bolt should sit on the inner lower surface of the hub assembly not on the face of the outer pulley which is a higher surface. The washer should be thick as mentioned above at least 3/8 inch and as large a diameter possible when sitting into that recess. As to the idea the torque needs to be extremely high heck the stock Flathead washer and bolt would never set at such high torque numbers the washer is to thin the bolt is mild steel and the thread is in a casting. Toque at 65 foot pounds is plenty thats all i ever use {on street engines and all out very fast engines} when the washer is thick enough and large enough in diameter to hold the pressure. Ronnieroadster __________________ I use the F word a lot no not that word these words Flathead , Focus and Finish. "Life Member of the Bonneville 200 MPH Club using a Ford Flathead block" Owner , Builder, Driver of the First Ford Flathead bodied roadster to run 200 MPH Record July 13, 2018 LTA timing association 200.921 in one and a half miles burning gasoline. First ever gas burning Ford flathead powered roadster to run 200 MPH at Bonneville Salt Flats setting the record August 7th 2021 at 205.744 MPH

09-14-2020, 03:03 AM	#29
Mart Senior Member Join Date: May 2010 Location: Solihull, England. Posts: 8,750	Re: Crank pulley bolt...Lost again!! Here's an idea. As you have bolts nearby, why not make a plate with a hex hole in the middle that drops over the bolt head and then has the other bolts going through it to lock it in place? Or some other sort of tab washer type device, or even some locking wire attached to an adjacent bolt. That said, a good bolt, a decent washer (turned up in a lathe as a custom job) and a spring washer ought to be all that is required. Just thinking out loud. Mart.

09-14-2020, 08:30 AM	#30
jimvette59 Senior Member Join Date: Jun 2010 Location: Perry OH Posts: 1,330	Re: Crank pulley bolt...Lost again!! Zeke3 the pulley is longer then the end of the crankshaft.

09-14-2020, 10:10 AM	#32
Zeke3 Senior Member Join Date: Dec 2014 Location: Columbus, IN Posts: 1,407	Re: Crank pulley bolt...Lost again!! The picture shows the crank nose, and inner hub and the accessory pulley. I assume the slot in the inner hub is for the keyway and the inner hub is installed such that it is pressing on the oil slinger and crankshaft gear. I would fill most of the gap between the nose of the crankshaft and the inner hub with a spacer, leaving the inner hub slightly higher than the spacer. Then use a thick washer, no larger than the outside diameter of the inner hub so it does not press on the accessory pulley, as Ronnie suggested. Also, a grade 5 capscrew will be perfectly adequate at 65 ft-lb torque. If that thing still falls out, I would safety wire it to one of the other bolts on the accessory pulley.

09-14-2020, 04:18 PM	#33
jrvariel48 Senior Member Join Date: Jan 2012 Location: New Jersey Posts: 1,425	Re: Crank pulley bolt...Lost again!! So I'm having my machinist make me a 3/8" thick washer at the proper diameter (1.750 OD) with a grade 8 bolt and the Nord-Lock system. I'll torque to 65-70 lbs and check it everytime I go for a ride. I also like the thought of tie wire and will do that if I find it loose again. I appreciate all the input and will post the results! Thanks again to everyone! Joe

09-14-2020, 04:23 PM	#34
glennpm Senior Member Join Date: Sep 2014 Location: Wiscasset, Maine Posts: 1,981	Re: Crank pulley bolt...Lost again!! That will be a good bolt up. Do yourself a favor and drill the bolt for safety wire now. If you find it’s getting loose, tighten it up and wire it. Glenn

09-14-2020, 04:58 PM	#35
Hal Beatty Senior Member Join Date: Jul 2012 Location: Bellingham, WA Posts: 213	Re: Crank pulley bolt...Lost again!! And I would have to agree with the safety wire suggestions. .041 diameter SS wire will hold a lot if it's properly installed.

09-15-2020, 05:58 AM	#37
glennpm Senior Member Join Date: Sep 2014 Location: Wiscasset, Maine Posts: 1,981	Re: Crank pulley bolt...Lost again!! It would be a good idea. If you don't want to use hex head bolts, maybe limited wrench clearance, use Allen head and drill those. Glenn

09-15-2020, 01:23 PM	#38
Tony, NY Senior Member Join Date: May 2010 Location: Capital of Corruption , NY Posts: 811	Re: Crank pulley bolt...Lost again!! I would also use regular socket screws (drilled). Some info on button head screws: "Button head screws, set screws, and studs cannot be torqued like ordinary screws. These screws have a small contact area where the tool is applied compared to other kinds of head types (e.g. hex, socket, cap, Torx, etc.) Torque on these screws must be reduced. If this is not done, either the screw, the piece being fastened, or the tool will be damaged."