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Posted by: DennisV Sep 24 2023, 11:25 AM

Decided to tackle rebuilding the steering components of our 1970 914-6 this weekend. I have done a lot of searching and YouTube watching, but still have a number of questions:

1. Why does the steering gear section of parts catalog explicitly state "Not for 914-6"? It sure looks like mine.
2. Why replace the entire inner tie rod end (i.e., threaded rod and metal housing) #5 instead of just the rubber insert? I see https://914rubber.com/inner-tie-rod-assembly-rebuild-kit. Metal fatigue?
3. Has anyone found a source for the housing cover gasket #4? If not, is https://www.permatex.com/products/gasketing/gasket-sealants/permatex-aviation-form-a-gasket-no-3-sealant-liquid-16-oz/ paste sufficient? Otherwise I guess it's cut a paper gasket?
4. Is there a current source for radial shaft seal #10? I am striking out on Porsche part number, http://www.914world.com/bbs2/index.php?s=&showtopic=273545&view=findpost&p=2299148, and dimensions at McMaster.
5. There are lots of aftermarket rubber options in this assembly. Anyone run into issues with lower cost options (e.g., URO)?

Posted by: 914Sixer Sep 24 2023, 05:42 PM

Rebuilding the steering rack is a job best left to experts. Requires special measuring tools.
Yes your steering rack is the same as the stock 914 BUT at assembly in Porsche plant they used a the 911 rack with 914 shaft. The 911 rack had a different openings. Starting in 1973 both 911 and 914 used the same rack up to 1989.

Posted by: r_towle Sep 24 2023, 05:45 PM

The bottom picture, the gear and all pieces to hold it in place.
I seem to recall there were three types (sizes of gear) over time
There was also a “quick rack” kit out there for less turning of the steering wheel.

I rebuilt a few back in the day, using other racks for parts…lots of measuring.

Posted by: Mikey914 Sep 24 2023, 09:39 PM

We originally planned to offer a rebuild kit. Problem is there are 6 variants that can fit into the 914. Of these each has other variations. That and the tolerance on racks require perfect alignment and tension must be set correctly on the drag puck. There are several variations of the drag puck as well as the bearings and even yokes.

We could put together kits, but the problem is identifying every variant, and then have to walk the customer through the rebuild without some of the required tools.

This is why we do it as a service.


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Posted by: Mikey914 Sep 24 2023, 09:49 PM

More


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Posted by: burton73 Sep 24 2023, 09:56 PM

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I just want to point out that the steering shaft going from the steering wheel with U -joints to the steering rack is a different length on the 1985 Carrera rack or a 1978 911sc rack. One is shorter and I cannot remember which one is which. Part #21 on drawings. You can clearly see the difference on the 911 one in my picture of my spare set up from an 85 Carrera 911.

Best Bob B

Posted by: Mikey914 Sep 24 2023, 09:57 PM

We vapor hone the castings and can provide Cerakote as an option.
Each shaft is polished, wear is checked and bushings honed to tolerances tighter than factory.
We reassemble with white lithium grease so you can see they have been completely cleaned.

The before and after. We have taken some that look like they were used as boat anchors and brought them back.

Our process is through. Sure you can disassemble and replace grease and bearings. They don't always go back together without binding.


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Posted by: Mikey914 Sep 24 2023, 10:03 PM

We do sell the assembled eyebolts as well as the kit mentioned
https://914rubber.com/rebuilt-eye-bolt-set-1

Please note that you get $30 back if you send in your cores. or buy just the bushing and shafts shown above. The big difference is we plated the the eye bolts and have done the work for you.
Mark


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Posted by: Mikey914 Sep 24 2023, 10:07 PM

We also carry the reduction rack new rack and pinion. Problem is that it will not work on all racks due to variation in castings, bushings and bearings. It will reduce the throw to 2.5 turns of the steering wheel.

Posted by: mepstein Sep 25 2023, 05:38 AM

Mark, what is the price to rebuild a 914 rack. I saw a couple different prices on the website. Thanks

Posted by: jhynesrockmtn Sep 25 2023, 07:14 AM

I rebuilt the front suspension of my Bumblebee this year. Everything but the carrier and torsion bars new. Added turbo tie rods as part of the process. I sent my rack to 914Rubber for rebuild as part of this process. Very happy with the results.

Posted by: technicalninja Sep 25 2023, 07:52 AM

I've rebuilt multiple rack and pinions over my automotive career.
I've done a 964 PS rack as I could find no-one local that I trusted.
Same with a rack out of a 93 Honda Prelude with 4-wheel steering.
Everyone and their uncle told me the Honda rack was the same for 2wh vs 4 wh.
They were all wrong!
It was significantly different and had I let someone else do it the 4wh steer would have never worked again!

By perusing this forum, I find that there are many different possible combinations for an early 914 rack.

Even with my extensive experience I'd just send mine to 914 rubber if I needed one...

Not worth the hassle if there are multiple variations.

Needs to go to someone who has seen and is aware of the pitfalls.

Posted by: Mikey914 Sep 25 2023, 10:44 AM

@http://www.914world.com/bbs2/index.php?showuser=10825

Here’s a video about what we do


https://youtu.be/fYrZ9Fga5JA


We have really 2 prices.
The more expensive for option A,B, and C is outright. We will refund the core, but charge enough to make sure it comes back if you send back in 90 days.

Type A
Outright https://914rubber.com/rebuild-service-for-steering-rack-type-a-rebuild-service-part-numbers-91434701001-91434701006-91434701401


Exchange https://914rubber.com/rebuilt-steering-rack-type-a-exchange

Steering rack Type A: Type A racks are the most common on 914's and even have a casting number that includes 914 in it. 914.347.010.01, 914.347.010.06, 914.347.014.01 are the casting numbers of the type A rack. They are part of the casting and not stamped.

Type B

Outright https://914rubber.com/rebuilt-steering-rack-type-b-zf-rack-part-number-91434701006

Exchange https://914rubber.com/rebuild-service-for-steering-rack-type-b-zf-rack-part-number-91434701006


Steering rack Type B: These racks are clearly marked ZF. They do not have placards, nor do they have the bulbous body like the C racks. They were interchangeable with 911s of the same period. They are completely different castings than the type A or C. A notable difference are the stampings: ( 7820 900 165 - 20 137 ), (7820 900 166 20 214 ), and (7826955 112 / 20 286 ).
Type C


Outright really depends on rack, many variables we may have what you need, we may not. Recommend dropping us an email with pictures Scott at 914rubber.com


Exchange https://914rubber.com/steering-rack-type-c-rebuild-service

The listing is a little confusing in that it looks like it’s a purchase, but we may not have stock to do so.


Steering rack Type C: There are several versions of Type C steering racks. Most are early 912, or 911 racks. They are characterized by the oversized bulb shape at the center. Known serial numbers are 78 20 501 115 and 78 20 900 129.


Hopefully the video helps.

Posted by: mepstein Sep 25 2023, 11:24 AM

I think I get it now. Thanks!

Posted by: DennisV Oct 7 2023, 12:02 PM

Setting the tension seems important, but other than that I'm not seeing what is dissuading folks from doing this themself. What are the pitfalls that am I missing?

Clearly there are variations and difficulty in finding some of the parts. Most of the bushing are https://914rubber.com/search/?q=steering. The few odd bits I had to source that might help others:

• Puck was on ours but broken. https://www.stoddard.com/sic34792900-90134792900-sic.html. I have read it is Delrin.
• Bearings seem to have several non-Porsche options, including https://www.stoddard.com/90005200700.html
• Radial shaft seal on ours was different size than I have seen in other posts (28 x 47 x7 mm). I found a dimensional https://www.zoro.com/dds-shaft-seal-28-x-47-x-7-mm-nitrile-rubber-284707tc/i/G6132939/
• Gasket I will cut my own. The one I removed was .25mm (1/64") thick. Found https://www.oreillyauto.com/detail/c/fel-pro/fel-pro-gasket-material/fel0/3045/v/a/17027/automotive-car-1970-porsche-914?q=1%2F64+gasket&pos=0.
• O-ring I will try to source from local hardware or parts store

On disassembly, ours looks pretty good save the broken puck. I'm going to give this a go this weekend. I might regret it down the road, but time will tell.

P.S. I'm not trying to take anything away from the service that Mark / 914 Rubber offer. The end results look great and they clearly have satisfied customers. I bought what parts I could from them.

Posted by: Montreal914 Oct 8 2023, 09:48 AM

YouTube video I found. I didn't see the Delrin piece in it though. This was solid metal. Delrin seems smoother, but maybe prone to wear faster?

https://www.youtube.com/watch?v=kjg82Gv_-Go

Posted by: DennisV Oct 9 2023, 02:23 PM

Here is a shot of ours after being disassembled and cleaned. I thought it might be of interest to others as it is a variation I have not seen in other threads or videos. The thrust ring is held in place by a threaded housing cover. There were no shims. I assume the tension is determined by how tight you screw it down.



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Posted by: Mikey914 Oct 9 2023, 03:30 PM

You are correct. The internal housing has to be removed to clean it throughout. If not any solvents used will get trapped diluting new grease and contaminating new grease.

We refer to this as a type c rack.