Steering, Suspension, & Brakes

tips, technology, tools and techniques related to non-driveline mechanical components

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rficalora
Rob Ficalora
Willis, TX
(2530 posts)

Registered:
10/24/2007 02:46PM

Main British Car:
'76 MGB w/CB front, Sebring rear, early metal dash Ford 302

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Proper tightening of FastCars IFS spindle nuts
Posted by: rficalora
Date: June 30, 2018 10:13AM

With the car on the lift, I noticed slight play in the hub/spindles on both sides. Thinking I want to disassemble, clean/inspect bearings, and reassemble before driving to Dayton. I've contacted Terry to find out what bearings and seals are used in case I need any. But, if they're still good (and I'm guessing they will be), I can reassemble this weekend.

Just need to know the right procedure to tighten the spindle nuts. Is it tighten till the hub doesn't rotate and then back off a flat on the nut to line up for a cotter pin? Specific torque? Anyone know?


ex-tyke
Graham Creswick
Chatham, Ontario, Canada
(1025 posts)

Registered:
10/25/2007 11:17AM

Main British Car:
1976 MGB Ford 302

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Re: Proper tightening of FastCars IFS spindle nuts
Posted by: ex-tyke
Date: June 30, 2018 10:53AM

Hub castellated nut should be positioned/cottered to allow about 2-5 thou end play .
The last time I played with my original MG hubs, I left out the shims, tightened the castellated nut and backed off to the closest cotter hole....checked end play with a dial indicator and verified within the 2-5 thou spec.


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(5606 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

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Re: Proper tightening of FastCars IFS spindle nuts
Posted by: BlownMGB-V8
Date: June 30, 2018 11:42AM

According to Timken, the inventors of the timken roller bearing, this type of bearing should be run under slight preload. Leaving clearance allows the rollers to skip and develop flat spots which cause them to run rough and accelerates wear. It also allows concentrated point contact between the outer end of the rollers and the outer bearing race.

Preload slightly deforms the outer bearing race, allowing full contact across the bearing rollers and providing positive drive of the bearing rollers. They are engineered and precisely manufactured to do exactly this. With a fresh, clean and oil free Timken bearing you can actually feel this by rotating the bearing between your palms. Under pressure the motion becomes smoother. Try it. You will see what I mean.

Don't overdo it. There is no need for heavy preload and it only generates heat. Spindle bearings are pretty forgiving of preload settings and MGB bearings are significantly understressed but it still should be done right. Tighten while rotating by hand until noticeable drag is felt and back off to the 1st cotter hole. That should be just about right. There should be no play and there should be very slight drag.

This whole business about play in MG spindle bearings got started with the early cars when they ran ball bearings and you had to have some play with those or you'd wear them out quickly because the balls would run on the side of the race where it was narrow and the balls only had very small point contact. When they upgraded to timkens they did not update the service procedure like everyone else did, thus causing mass confusion. Follow the bearing inventor, engineer and manufacturer's recommendation. If you don't trust me on this, go to Timken.com and research tapered roller bearing preload. You will find a complex method that measures actual preload pressure and is extremely precise. You don't need to do that. As I said, spindle bearings are forgiving. They will live a long time under inexact preload as long as there is some. With none the service life drops off precipitously. Timken has graphs of that too.

Jim



Edited 2 time(s). Last edit at 06/30/2018 11:45AM by BlownMGB-V8.


ex-tyke
Graham Creswick
Chatham, Ontario, Canada
(1025 posts)

Registered:
10/25/2007 11:17AM

Main British Car:
1976 MGB Ford 302

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Re: Proper tightening of FastCars IFS spindle nuts
Posted by: ex-tyke
Date: June 30, 2018 01:29PM

Quote:
Don't overdo it. There is no need for heavy preload and it only generates heat.
I'll say....at this point the wheel won't turn!
I think we both essentially agree that tightening the nut to about 10 ft.lb while turning the wheel will set the bearings and then backing off the nut to the closest cotter hole will give Rob what he needs.


rficalora
Rob Ficalora
Willis, TX
(2530 posts)

Registered:
10/24/2007 02:46PM

Main British Car:
'76 MGB w/CB front, Sebring rear, early metal dash Ford 302

authors avatar
Re: Proper tightening of FastCars IFS spindle nuts
Posted by: rficalora
Date: July 02, 2018 10:36AM

I don't know Graham. Sounds like an agree to disagree to me. The procedure you're describing is the same as the stock MG spindle procedure. Maybe I'm wrong, but w I'm hearing Jim say is leave a little pre-load on the bearings which, I think, would leave no end play. I'm more comfortable with your approach as the FastCars tapered spindles and timkin style bearings are the same design as the MG and right or wrong, that procedure has worked there for 40+ years.


Dan B
Dan Blackwood
South Charleston, WV
(940 posts)

Registered:
11/06/2007 01:55PM

Main British Car:
1966 TR4A, 1980 TR7 Multiport EFI MegaSquirt on the TR4A. Lexus V8 pl

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Re: Proper tightening of FastCars IFS spindle nuts
Posted by: Dan B
Date: July 02, 2018 10:54AM

Look at this video. Jim and Graham are saying the same thing Timken says.

[youtu.be]


ex-tyke
Graham Creswick
Chatham, Ontario, Canada
(1025 posts)

Registered:
10/25/2007 11:17AM

Main British Car:
1976 MGB Ford 302

authors avatar
Re: Proper tightening of FastCars IFS spindle nuts
Posted by: ex-tyke
Date: July 02, 2018 11:28AM

Quote:
Look at this video...
Perfect....that sums it up nicely!



rficalora
Rob Ficalora
Willis, TX
(2530 posts)

Registered:
10/24/2007 02:46PM

Main British Car:
'76 MGB w/CB front, Sebring rear, early metal dash Ford 302

authors avatar
Re: Proper tightening of FastCars IFS spindle nuts
Posted by: rficalora
Date: July 02, 2018 11:22PM

Yep. I talked with Terry this morning. Procedure he follows is similar to this.


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(5606 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

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Re: Proper tightening of FastCars IFS spindle nuts
Posted by: BlownMGB-V8
Date: July 03, 2018 11:12AM

Interesting that Timken would put that video out there. So far as I am aware there is no difference between the bearings used for front end spindles and those used for other spindle types such as machine tools, axle pinions and even differentials. The materials are the same, the design is the same, and even the race angle is the same. Anyone who has ever done any drive axle work is or should be well aware of the preload requirements there which are not what you would call light, and which is similar to that used in all types of machinery. This recommendation of actual clearance or end play in the bearing is a departure from their recommendations for all other types of tapered bearings in all other applications.

The only reason I can see for it is that people do it wrong and they are covering their back side. As you can see from their failure examples it is better to err on the side of looseness than having it too tight. In our litigation prone society, any recommendation to close up the clearance can be twisted into an interpretation that the company told the owner to crank that puppy down, making the company responsible as an insurer for any and all damages that might result. I don't blame them for protecting themselves in the face of such nonsense, and the clearance they therefore recommended is still tight enough for the bearing to work reasonably well for a reasonable length of time.

It ain't right, but it's better than being sued.

Jim


ex-tyke
Graham Creswick
Chatham, Ontario, Canada
(1025 posts)

Registered:
10/25/2007 11:17AM

Main British Car:
1976 MGB Ford 302

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Re: Proper tightening of FastCars IFS spindle nuts
Posted by: ex-tyke
Date: July 03, 2018 01:15PM

In my experience, any side load on the bearing (no end play) adds friction to the bearing to the point where it won't turn freely.....not what you want for a wheel!


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(5606 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: Proper tightening of FastCars IFS spindle nuts
Posted by: BlownMGB-V8
Date: July 03, 2018 06:27PM

I think it's a question of how much. Timkins were designed specifically to handle a combination of axial and side loading, which is the reason the rollers are set at an angle. Consider a Lathe or mill spindle for instance. It would be unusable in today's machines if the bearings had end play because that would generate both chatter and inaccuracy. Those bearings are no different other than being ground a bit more accurately. They also handle rather incredible amounts of thrust loading, for instance in a drilling operation with a very large drill bit. Consider also the loading on spindle bearings when a car goes around a corner. That results in a much higher thrust loading than a nominal bearing preload.

One feature of a tapered bearing is that as a side load is applied the bearing compresses, which makes it thinner, meaning a hub with end play going around a corner will have even more end play. How much? Well Timken has graphs for that too. It isn't a great deal but is very much dependent on the amount of pressure applied.

And yes, If you really crank down on the spindle nut, you can reach the point where the hub is difficult to turn. I can remember in the old days spinning a tire with one hand and cranking down the nut hard with a ratchet in the other to stop the tire in an effort to seat the bearing races in the hub. The bearings will survive that loading just fine at low speed and with adequate lubrication but it is way too tight to run at any sort of speed and would generate excess heat which would ultimately damage the bearing. The video clip showed the damage caused that way as well as the damage caused by clearance. At both ends of the scale the bearing components are being damaged by improper installation, the question is where in between is best for maximum bearing life? Clearly heat is to be avoided as more severe damage is likely at that end so overly tight preload should be avoided. But, differential carrier bearings are usually installed with .010" of preload and if you use less you can expect to develop axle noise. To me this says that .010" preload on spindle bearings is going to be a little on the tight side just because they run in grease rather than an oil bath and therefore are not as well lubricated.

That gets us down to the -.010" to +.005" clearance range. Realistically as long as your spindle bearings are in that range they should be OK. Optimally you would split the difference, meaning that you'd have a few thou preload but less than 10. My opinion is that -.005" is a good number. Tight enough for excellent hub control and positive tracking of the rollers in the races to avoid slippage, low enough to avoid heat build up.

Jim


88v8
Ivor Duarte
Gloucestershire UK
(603 posts)

Registered:
02/11/2010 04:29AM

Main British Car:
1974 Land Rover Lightweight V8

Re: Proper tightening of FastCars IFS spindle nuts
Posted by: 88v8
Date: July 06, 2018 08:02AM

Hmm, interesting

I remember the front hubs in the MGC had to have preload, set with shims.

Otherwise, it's always been tighten and back off. The Rambler, the Lanchester, the Land Rover, the TR6, all had/have factory end
float in the region of 2-4 thou. Mostly a cotter pin. With the Landy it's a big locknut.
For the TR6, there's a stiffening mod with a spacer and shims, but that just bakes in the end float.

Otoh, the pinion of the Salisbury axle in the Landy has to have some preload.

Ivor


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(5606 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: Proper tightening of FastCars IFS spindle nuts
Posted by: BlownMGB-V8
Date: July 06, 2018 11:05AM

Look at how they are setting the spindle bearings on new cars (RWD of course). That should show the current trend.

Jim


rficalora
Rob Ficalora
Willis, TX
(2530 posts)

Registered:
10/24/2007 02:46PM

Main British Car:
'76 MGB w/CB front, Sebring rear, early metal dash Ford 302

authors avatar
Re: Proper tightening of FastCars IFS spindle nuts
Posted by: rficalora
Date: July 07, 2018 08:38PM

New dilemma... Local auto parts place said they had the bearings and seals so I took the driver side hub off to inspect. Cleaned the outer bearing and it and the race look fine... But decided to go get the seal before removing the existing one. It was way off. Called around and found a close one but it's not the same. And the grease in the hub is blue - looks like marine grease.

So, here's the dilemma... If I remove the seal (assuming it'll get damaged in the process) and the new one doesn't fit, I'm stuck.

If I don't remove it and just repack the outer bearing and reinstall, what grease to use? Marine grease looks the same but specifically says not for disk brake hubs. But, it also says it's compatible with white lithium grease so so I'm not sure it will be compatible with the hi temp bearing grease I have (if it is actually marine grease).


I'm supposed to head to Dallas tomorrow, work from there Monday, then head out for Dayton on Tuesday. Anyone know enough about grease compatibility? Or have Terry's phone number so I can find out what he uses?
IMG_20180707_182750-1024x768.jpg
IMG_20180707_182815-1024x768.jpg
IMG_20180707_182901-1024x768.jpg


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(5606 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: Proper tightening of FastCars IFS spindle nuts
Posted by: BlownMGB-V8
Date: July 08, 2018 09:32AM

They used a more modern seal, there should be a number on it somewhere. Also it's likely that if you are careful and use a curved prybar (I made one out of a 1/4" screwdriver and rounded the corners) you should be able to remove the old seal without damaging it. Looks like it probably has a rubber outer diameter and should come out easily.

There are an extremely high number of greases available. Semi operators went to a red grease a few decades back which is very good and then to a green water resistant grease about a decade ago. Every oil manufacturer makes their own versions of those two, so just find one that doesn't warn against using it with disc brakes and you should be good.

My opinion is that for a non-washdown application the red grease is probably a little better, but for washdown (like lawnmowers for instance) the green is better. They are both far superior to lithium and the other old greases available when the cars were built.

Jim



rficalora
Rob Ficalora
Willis, TX
(2530 posts)

Registered:
10/24/2007 02:46PM

Main British Car:
'76 MGB w/CB front, Sebring rear, early metal dash Ford 302

authors avatar
Re: Proper tightening of FastCars IFS spindle nuts
Posted by: rficalora
Date: July 08, 2018 10:10AM

Thanks Jim. I've removed seals without damaging them, but I've also ruined my share when I thought they should come out. I'm hesitant to try till I have a replacement that I'm sure will work. The seal # I got from Senneker is an SKF 692447. No one around here seems to have it or be able to find a cross reference for it. I found some pics on line that say it's 38mmx52mmx7mm. National 1174 is close, but none of the local shops have it.

If I can get ahold of Terry I could find out what grease he uses and avoid taking the chance of not having a seal to use - then I'd really be stuck!


ex-tyke
Graham Creswick
Chatham, Ontario, Canada
(1025 posts)

Registered:
10/25/2007 11:17AM

Main British Car:
1976 MGB Ford 302

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Re: Proper tightening of FastCars IFS spindle nuts
Posted by: ex-tyke
Date: July 08, 2018 11:31AM

Rob,
Just checked an old seal box I had kept from the last time I changed seals -
Box has NAPA brand logo ....seal is part no....SKF 18962

MGb front hub seal 2.jpg


rficalora
Rob Ficalora
Willis, TX
(2530 posts)

Registered:
10/24/2007 02:46PM

Main British Car:
'76 MGB w/CB front, Sebring rear, early metal dash Ford 302

authors avatar
Re: Proper tightening of FastCars IFS spindle nuts
Posted by: rficalora
Date: July 08, 2018 11:50AM

That's interesting Graham. 48x62x8 is pretty far off from 38x52x7. That seal is for a FastCars suspension?
If so, I wonder if they changed spindles/hubs at some point?


ex-tyke
Graham Creswick
Chatham, Ontario, Canada
(1025 posts)

Registered:
10/25/2007 11:17AM

Main British Car:
1976 MGB Ford 302

authors avatar
Re: Proper tightening of FastCars IFS spindle nuts
Posted by: ex-tyke
Date: July 08, 2018 11:55AM

That's true, Rob...I wasn't thinking - what I gave was seal info for the original MGB front hubs....sorry!


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(5606 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: Proper tightening of FastCars IFS spindle nuts
Posted by: BlownMGB-V8
Date: July 08, 2018 12:50PM

Motion Industries has that seal"
[www.motionindustries.com]

Should be one in any large city near you I'd think.

Jim
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