HOW TO DO AN ADVANCED SEARCH.

Mon Jul 08, 2013 3:56 pm by Admin


For the benefit of 944Hybrids users there are two search functions available for you to use.
The purpose of this sticky is to explain the "Advanced Search" function because it is much more powerful and is the best choice when researching information.

When you log on to the site a list of options is shown in a line at the top of the page. One option is labelled "Search", use this option (NOT the search box lower down on the right).

After you click on the upper search option, a drop down box appears. At the bottom of this box is a radio button marked "Advanced …

Comments: 0

Latest topics
» Rebuilt engine threw three rods
Today at 8:45 pm by jpkinerk

» 1984 Gen IV 5.3 Swap
Sun Dec 03, 2017 11:54 am by superman22x

» Aluminum 5.3 swap
Sat Dec 02, 2017 8:59 pm by turbobob924

» Power and Torque figures
Sat Dec 02, 2017 12:27 pm by Fubar

» Aftermaket Seat Options
Sat Dec 02, 2017 9:04 am by Jchard944

» 83' Porsche 944 LM7 Build
Thu Nov 30, 2017 9:47 pm by Jchard944

» 948 Badges - Just in time for Christmas
Wed Nov 29, 2017 7:59 pm by Admin

» Atlanta area cars and shops
Wed Nov 29, 2017 10:49 am by Bmillar

» New convert under way
Mon Nov 27, 2017 1:34 pm by kevin924kevin

» Did anyone do a before and after weight?
Sun Nov 26, 2017 11:44 am by murrayg

December 2017
MonTueWedThuFriSatSun
    123
45678910
11121314151617
18192021222324
25262728293031

Calendar Calendar

Log in

I forgot my password


Torque tube bearing inspection

Page 2 of 2 Previous  1, 2

View previous topic View next topic Go down

Re: Torque tube bearing inspection

Post  marc a on Thu Feb 21, 2013 7:44 pm

Somewhere on Rennlist there is a long thread on the use of C4 bearings. I think it was a combination of heat build up in between the bearing carriers with no way to escape, and Porsche over-engineering.


watsondk wrote:Good find on actualy C4 bearings.

Not entirely sure why they used C4's from the factory, I can't imagine temperatures being that extreme in the TT, and while the bearings are in there tight a lot of that is due to the rubber insert's friction. I'm guesing the heat from the catalytic converter and exhaust? Any ideas of typical temperatures of the TT?
avatar
marc a

Posts : 170
Join date : 2009-07-18
Location : Herndon, Va

Back to top Go down

Torque Tube Bearing Carriers

Post  watsondk on Wed Mar 20, 2013 8:20 pm

So as I pulled out my torque tube bearings a few weeks ago I had an "incident". The outer bearing carriers got scraped. I'm sure I'm not the only one this has happened to (like the first post of this thread). Sad

Would anyone be interested in buying some newly designed and made carriers?

Basically I will be reusing the outer rubber to insure the carriers don't "walk" inside the TT but replacing the metal shell with delrin. I will post pictures of the final product and let everyone know if they work when they are complete.

I will have enough material to make several extra carriers if they are successful. For now I will only make enough for myself, however if others are interested I could have the machine shop use the rest of the material I purchased and sell at cost.

I will also have extra material for the inner inserts, although I believe those are available from other sources unlike the carriers.
avatar
watsondk

Posts : 33
Join date : 2012-01-20
Location : Detroit, MI

Back to top Go down

Bearing carriers

Post  fliermike45 on Wed Mar 20, 2013 9:13 pm

Guess you are re-inventing Constantine's wheel.........It's a joke..

fliermike45

Posts : 778
Join date : 2009-09-19

Back to top Go down

Re: Torque tube bearing inspection

Post  watsondk on Wed Mar 20, 2013 9:28 pm

Only to the extent needed to do the job properly. His setup is truly above and beyond oem, I am simply trying to replace unavailable parts at a reasonable cost.
avatar
watsondk

Posts : 33
Join date : 2012-01-20
Location : Detroit, MI

Back to top Go down

Re: Torque tube bearing inspection

Post  acorad on Thu Mar 21, 2013 12:46 pm

watsondk wrote:Only to the extent needed to do the job properly. His setup is truly above and beyond oem, I am simply trying to replace unavailable parts at a reasonable cost.
Seems like a reasonable idea.
avatar
acorad

Posts : 645
Join date : 2010-12-21
Location : Agoura Hills, CA

Back to top Go down

Re: Torque tube bearing inspection

Post  backpack09 on Wed Mar 27, 2013 2:03 pm

I am a cheap SOB, so I am interested dependant upon price.

backpack09

Posts : 12
Join date : 2012-09-02
Age : 36
Location : Whitman Mass

Back to top Go down

Re: Torque tube bearing inspection

Post  watsondk on Wed Mar 27, 2013 2:24 pm

I pick them up tomorrow after work but already have pictures. I will try to upload them tonight. I plan on installing them Friday (4 day week!!!). Will update with how well they install and again with how they work once the car is back on the street.

I will ask the machinist if he would be willing to make more sets and at what price.
avatar
watsondk

Posts : 33
Join date : 2012-01-20
Location : Detroit, MI

Back to top Go down

Re: Torque tube bearing inspection

Post  watsondk on Wed Mar 27, 2013 8:06 pm

Here are the pieces, picking them up from the machine shop tomorrow:

The inner pieces are the basic design from clarks-garage.
[You must be registered and logged in to see this link.]

[You must be registered and logged in to see this link.]

The outer pieces are the important ones, if you have messed up bearing carriers and don't want to buy a new TT assembly these might be for you (if they actually work, which I will find out soon). The bearings are press fit tightly into the delrin. As things heat up the metal has a higher coefficient of expansion and the press fit will become tighter. This design reuses the rubber ring from the bearing carriers. If your rubber pieces are scrapped as well these could be made to work with o-rings with a design change.

[You must be registered and logged in to see this link.]

[You must be registered and logged in to see this link.]
avatar
watsondk

Posts : 33
Join date : 2012-01-20
Location : Detroit, MI

Back to top Go down

Re: Torque tube bearing inspection

Post  acorad on Wed Mar 27, 2013 9:10 pm

Very interested in the results.
avatar
acorad

Posts : 645
Join date : 2010-12-21
Location : Agoura Hills, CA

Back to top Go down

Re: Torque tube bearing inspection

Post  backpack09 on Thu Mar 28, 2013 8:57 am

Those things look effing awesome. I hope they work!

backpack09

Posts : 12
Join date : 2012-09-02
Age : 36
Location : Whitman Mass

Back to top Go down

Re: Torque tube bearing inspection

Post  watsondk on Mon Apr 01, 2013 7:06 am

Spent some time with the parts this weekend. The machinist didn't exactly do a steller job and I ended up getting a partial refund from him. Of the 8 bushings he made 2 of them met the specs on the drawings I provided...

The two parts that were correct worked great, the other six...well not so much No

The main issue is that I specified an interference press fit and the bearings ended up loose in the bushings. He was up to .015" off specified dimensions on some of the ID and OD's which is horrible for a material as easy to machine as delrin. I have been adding epoxy and sanding to get the correct dimensions for the assembly, new plan is to have them installed this next weekend.

I will update after they are in.

avatar
watsondk

Posts : 33
Join date : 2012-01-20
Location : Detroit, MI

Back to top Go down

Re: Torque tube bearing inspection

Post  acorad on Mon Apr 01, 2013 8:36 am

What epoxy did you find that adheres to delrin?
avatar
acorad

Posts : 645
Join date : 2010-12-21
Location : Agoura Hills, CA

Back to top Go down

Re: Torque tube bearing inspection

Post  watsondk on Tue Apr 02, 2013 5:14 am

I roughed up the delrin with some 60 grit paper and used some "5-minute" 2 part epoxy. I test fit the assemlblies to the driveshaft outside of the TT. I adjusted them until they installed with about the same effort as the stock metal/rubber insert. Didn't have any issues with the epoxy seperating when inserting driveshaft. Time will tell though.
avatar
watsondk

Posts : 33
Join date : 2012-01-20
Location : Detroit, MI

Back to top Go down

Re: Torque tube bearing inspection

Post  v8carreragts on Mon Apr 08, 2013 7:47 am

You might want to look for a tube from a car newer than '86 because the pucks are designed better. The rubber "belt" is bonded to the bearing carrier and the bearings press in rather than the carrier being two piece with the bearing sandwiched in between.

Funny, I just did mine this weekend and my G31 tube (1980) had bonded rubber and pressed in bearings and the 1983 944 tube was the same.

Should be C4 clearance, not C3. All of the TT that I rebuilt and/or gutted had "C4" on the outer bearing surface. YMMV

Both of mine had bearings that just say FAG 6006 with no clearance designation which means that they are C2-C3. (normal clearance) I used C3 which are tighter than C4. The ones I used are rated for 8000 RPM and rated for 250 deg C.
avatar
v8carreragts

Posts : 327
Join date : 2009-06-08
Age : 60
Location : Tucson, AZ

Back to top Go down

Re: Torque tube bearing inspection

Post  backpack09 on Wed Apr 24, 2013 1:18 pm

I am guessing the lack of a followup means that these instantly melted and dripped out the back of the torque tube... Please prove me wrong!

backpack09

Posts : 12
Join date : 2012-09-02
Age : 36
Location : Whitman Mass

Back to top Go down

Re: Torque tube bearing inspection

Post  watsondk on Wed Apr 24, 2013 1:28 pm

The parts were actually succesful, just way too much effort.

This past weekend I completed an 850 mile road trip with some very spirited driving without issues from the TT bearings...I did have the FL tire blowout on me but thats unrelated.

To recap I had custom delrin bearing carriers machined to accept the rubber surrounds from the stock pieces. The bearings were then supposed to press fit into the delrin carriers. The machinist did a pretty dismal job so I ended up using a two-part epoxy to secure the bearings into the carriers.

I then pressed the smaller delrin inserts into the bearings. These were supposed to be a tight fit aroud the driveshaft...again the machinist let me down, they were way out of spec. I initially attempted to use epoxy for that as well. The epoxy proved too brittle, cylinder head RTV worked very well though.

When inserting the carriers into the TT I soaped them up to get them in easier. My first attempt was without soap and the rubber surround attempted to come off the carrier.

The only noise now is some clutch chatter and a slightly undersized/worn driveshaft nub.

If I were to do it again I would probably find a used TT and pull good carriers/inserts from it.
avatar
watsondk

Posts : 33
Join date : 2012-01-20
Location : Detroit, MI

Back to top Go down

TT

Post  fliermike45 on Wed Apr 24, 2013 2:42 pm

Or go to the expert.....

fliermike45

Posts : 778
Join date : 2009-09-19

Back to top Go down

Re: Torque tube bearing inspection

Post  Sponsored content


Sponsored content


Back to top Go down

Page 2 of 2 Previous  1, 2

View previous topic View next topic Back to top

- Similar topics

 
Permissions in this forum:
You cannot reply to topics in this forum