Home  |  Forums  |  914 Info  |  Blogs
 
914World.com - The fastest growing online 914 community!
 
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG. This site is not affiliated with Porsche in any way.
Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners.
 

Welcome Guest ( Log In | Register )

 
Reply to this topicStart new topic
> Installing bearing races in front hubs with dry ice or heat, Anyone try it?
bdstone914
post Jun 19 2016, 07:10 AM
Post #1


bdstone914
****

Group: Members
Posts: 4,725
Joined: 8-November 03
From: Riverside CA
Member No.: 1,319



I have always found these to be a PITA to install. I have tried installing the rear bearings after freezing them and cant see any difference.
If expansion and contraction are proportional to the temperature then dry ice at -109 F should make a big difference. Used in combination of putting the 911 front hub in the oven at 250-300 degrees I am hoping the races will drop right in.
Anyone tried it or have an easy method without the proper too size puller tools?

User is offlineProfile CardPM
Go to the top of the page
+Quote Post
mgp4591
post Jun 19 2016, 08:01 AM
Post #2


914 Guru
*****

Group: Members
Posts: 5,489
Joined: 1-August 12
From: Salt Lake City Ut
Member No.: 14,748
Region Association: Intermountain Region



I haven't changed mine out but every other German vehicle I've worked on has little gaps in the backside of the hubs behind the races - I take my punch and walk them out. My set of race install tools weren't that expensive either but then I was making my living with them so the expense was negligible. Before I bought them though, I'd take the old races and stack them on the new ones and gently tap them into place.
I'd think your idea of dry ice or just putting them in the freezer for hours will work fine.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
stugray
post Jun 19 2016, 08:10 AM
Post #3


Advanced Member
****

Group: Members
Posts: 3,825
Joined: 17-September 09
From: Longmont, CO
Member No.: 10,819
Region Association: None



I have just driven the old ones out like mqp4591 explained above.
The new ones I drive in at room temp with the harbor freight aluminum bearing driver tool and a BFH.

I have even driven out a new set of bearings and driven them back in (wrong rotors on first attempt) and they seem to be holding up fine, but my car is not a high mileage vehicle.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Valy
post Jun 19 2016, 08:52 AM
Post #4


Senior Member
***

Group: Members
Posts: 1,677
Joined: 6-April 10
From: Sunnyvale, CA
Member No.: 11,573
Region Association: Northern California



Oven and freezer work great but you have to use a race driver or else it's very difficult to drive them square. And if it takes you more than few seconds to drive them in then the temp of the race will match the temp of the rotor and you lose that advantage.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Mueller
post Jun 19 2016, 09:11 AM
Post #5


914 Freak!
***************

Group: Members
Posts: 17,150
Joined: 4-January 03
From: Antioch, CA
Member No.: 87
Region Association: None



Been awhile since i have done 914 wheel bearings, but last couple of cars I've done I bought the cheap Harbor Freight driver kit for races. Worked great.

Race in freezer (hour?), used a heat gun laying on ground pointing towards hub area for a few minutes
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
toolguy
post Jun 19 2016, 12:20 PM
Post #6


Senior Member
***

Group: Members
Posts: 1,275
Joined: 2-April 11
From: San Diego / El Cajon
Member No.: 12,889
Region Association: Southern California



Nothing beats getting them in smoothly than a little grease and use a threaded rod and nut / race adapter to pull them in slowly and straight . . the trick is starting them straight and flush before starting so there is no galling which occurs when they race walls are not parallel to the hub walls. Once you get a gouge and chip started it only gets worse.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
76-914
post Jun 19 2016, 12:37 PM
Post #7


Repeat Offender & Resident Subaru Antagonist
**********

Group: Members
Posts: 13,638
Joined: 23-January 09
From: Temecula, CA
Member No.: 9,964
Region Association: Southern California



Or the correct O.D. Harbor Freight impact socket and a hammer. And Dave said it. Start square. You can hear and feel if it is square by the sound of the hammer striking.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
bdstone914
post Jun 19 2016, 01:19 PM
Post #8


bdstone914
****

Group: Members
Posts: 4,725
Joined: 8-November 03
From: Riverside CA
Member No.: 1,319



QUOTE(toolguy @ Jun 19 2016, 11:20 AM) *

Nothing beats getting them in smoothly than a little grease and use a threaded rod and nut / race adapter to pull them in slowly and straight . . the trick is starting them straight and flush before starting so there is no galling which occurs when they race walls are not parallel to the hub walls. Once you get a gouge and chip started it only gets worse.

(IMG:style_emoticons/default/agree.gif)

I found there was a tool in the collection I bought. The oven heat to 250 on the hubs and freezer on the bearing races made no difference. I pulled them in with the tool using the complete bearing and had them done quickly.
Thanks to all who replied.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
A&P Mech
post Jun 19 2016, 04:30 PM
Post #9


Member
**

Group: Members
Posts: 401
Joined: 10-September 13
From: United States
Member No.: 16,371
Region Association: Rocky Mountains



I just purchased new rotors and bearings from PMB, so I will be attempting this as well. My local O'Reillys has a "bearing race and seal driver set" as part of their tool loaner program.

http://www.oreillyauto.com/site/c/RentalTo...ord=tool+rental

It is shown in the first column third row. Is what I should use?

Ray
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
r_towle
post Jun 19 2016, 05:06 PM
Post #10


Custom Member
***************

Group: Members
Posts: 24,646
Joined: 9-January 03
From: Taxachusetts
Member No.: 124
Region Association: North East States



Did the 911 with hub on the stovetop and race in the freezer, used old race to hammer in new race flush. Been doing it that way my whole life, never failed
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
veekry9
post Jun 19 2016, 06:43 PM
Post #11


OldMember
****

Group: Retired Members
Posts: 3,068
Joined: 17-June 13
From: TO
Member No.: 16,025
Region Association: Canada



https://www.google.ca/search?q=induction+he...UTqATAQ_AUIBigB
https://www.google.ca/search?q=high+speed+s...eating+oil+bath

Check the temperature of your shaft and bearings,calculate size at standard ambient.
Check your clearance by measuring,write it down,calculate the interference dimension.
Heat the female and cool the male.Insert.
(IMG:style_emoticons/default/happy11.gif)
https://www.google.ca/search?q=high+speed+s...RY6ALwQ_AUIBigB
https://www.google.ca/search?q=high+speed+s...+spindle+design
https://www.google.ca/search?q=high+speed+s...=shaft+bearings


https://www.youtube.com/watch?v=LVODJm05plw

/
https://www.google.ca/webhp?sourceid=chrome...bearing+fitting
/
04-24-2006, 10:16 PM
Forrest Addy
Bremerton WA USA

"Freezing a bushing to -78F(Co2) or even - 320F(N2) gives you a limited amount of shrink. Compounding the difficulty of assembly is the cold bushing accumulates iron hard ice from the humidity in the moment it emerges into the ambient air from the dry-ice, lN2 whatever have gurgling away in the coffee can. The ice accumulation begins the instant the bushing is exposed to air and continues until the ice melts. It takes only a few seconds.

As soon as the bushing makes contact with the warm bore the hard ice may prevent assembly. The ice soons melt and in doing so pumps a lot of heat into the formerly cold bushing. This is a bushing with a thin wall. It has very low thermal mass and a lot of area. Unless the thermal equilibrium interference is small, forcing the bushing into place with rough expedients may result in buckling it. Better make a bushing driver just in case.

If you can heat the mating part to 300 degrees you get that much more assembly clearance and a chance for a slip-in-place assembly. An hour with a 30K BTU IR heater focused on the spot will heat the bore gently.

Calculate your shrink allowance and assembly interference carefully. Success or failure depends on shop arithmetic and a knowledge of coefficients of thermal expansion."

http://www.practicalmachinist.com/vb/gener...rink-fit-89092/
/
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
matthepcat
post Jun 20 2016, 09:03 AM
Post #12


Meat Popsicle
***

Group: Members
Posts: 1,462
Joined: 13-December 09
From: Saratoga CA
Member No.: 11,125
Region Association: Northern California



For the rear bearings I found that you have to freeze the bearing overnight to be effective. I also had success with dry ice/ rubbing alcohol bath.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Mark Henry
post Jun 20 2016, 10:09 AM
Post #13


that's what I do!
***************

Group: Members
Posts: 20,065
Joined: 27-December 02
From: Port Hope, Ontario
Member No.: 26
Region Association: Canada



QUOTE(r_towle @ Jun 19 2016, 07:06 PM) *

used old race to hammer in new race flush.

(IMG:style_emoticons/default/agree.gif)
To get proper size driver I take the old race and my bench grinder, I spin the race as I grind the OD. In a few minutes you have a slightly undersize driver that works perfectly.
I have a whole collection of them. (IMG:style_emoticons/default/shades.gif)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post

Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 



- Lo-Fi Version Time is now: 8th December 2024 - 01:45 PM