my new 911 T to Rs project

dizzycap · Post by **dizzycap** » Thu Oct 08, 2009 10:34 am

there are (atleast) two types of bolts used. I can't figure out what model year your car (or more to the point, your struts) is, but MY 1969-1970-ish have ordinary bolts, while later ones have the wedge-type Cortina mentions. They have different ball joints as well, depending on bolt/wedge bolt.

My parts delaer told me my 1970 struts could be modified to take the much more common wedge type ball joints, but in the end we sourced the right ones. Could take a pic of my struts if you want.

Check the date markings on your struts if you want to be 100% sure.

//Marcus

500gls · Post by **500gls** » Thu Oct 08, 2009 10:46 am

Hi I am sure I do NOT have the wedge type bolt because my other car has those and the bal joints are different for them as well. this type I have now is for the normal bolt BUT I think it needs to be non threaded at the beginning because it makes contact with the ball joint there.
hope this makes sense.

Cortina · Post by **Cortina** » Thu Oct 08, 2009 11:04 am

Fine , but part is still wrong (my opinion) - load (not that there is much) should be taken on the non threaded part of bolt (I assume there is a "groove" in the btm fitting which the bolt passes through). Threads the whole way would do as a get you home measure , but my guess is , it's not correct.

dizzycap · Post by **dizzycap** » Thu Oct 08, 2009 12:37 pm

i agree with Cortina. should be a bit of non-threaded under the head of the bolt. I can try and make sense of it when i'm in the garage tonight, but i know i've lost my bolts too.

dizzycap · Post by **dizzycap** » Fri Oct 09, 2009 7:52 am

ok. i had a look at my struts/balljoints/bolts last night (i knew havíng the whole car in parts would come in handy one day

).

i've lost the bolts that were used to fix the balljoint to the strut, but from recollection i don't remeber them being part-threaded. I've looked around fastener-sites and can't seem to find any part-threaded 30mm M10 bolts so maybe they actually used a standard fully-threaded bolt.

Regardless, the non threaded part of an M10 bolt fits like a glove in the grove on the ball joint, so my thought now is to buy a part-threaded M10 bolt, hacksaw it to length (30mm). I might have to give it a go with the threader (is that the word? for making threads on bolts/rods etc.), but that should allow the balljoint to rest, at least partially, on a non-threaded bolt, rather than on threads alone.

500gls · Post by **500gls** » Fri Oct 09, 2009 11:36 am

that's the way to go !

bas

911hillclimber · Post by **911hillclimber** » Fri Oct 09, 2009 4:31 pm

I have limited experience of these bolts on my 911 (1973)

However, the car has had Boge and now Bilstein struts and both struts are the same connection to the ball joint.

The 'bolt' on my car is a special pin, wedge shaped and slightly tapered. On the one end there is a thread (M6 iirc) that is 'outside' of the clamping area. The action of the pin is to wedge the ball joint shaft (with the flat machined in one side) to the bore in the strut. This wedging action is secured tighter by the clamping action of the M6 nut when tight.
(I add a dab of green Loctite on my nuts...)

All of these engineering forms are there for a reason as they are expensive parts to make; I think I paid £15 each new for mine about 18 years ago when the Bilsteins went on.
They are heat treated steel.

Take care. There is a lot of load on the ball joint/strut/wishbone and if there is a bit of play, it will over time get greater and at least wear beyond use the struts (they are the softest material in the whole assembly) or worse, they will come apart and the car will not be at a standstill when that happens, but soon will be shortly after failure.

dizzycap · Post by **dizzycap** » Mon Oct 12, 2009 7:40 am

just to conclude this. I found the bolts that i removed when i took my front struts apart and they were standard 8.8-steel, fully threaded M10. I believe them to be the original bolts.

I also did the mod i was referring to and sure, custom-threading an M10 does help the bolt rest a bit more on a flat part of the bolt, but tbh, it isn't too much difference from a standard part threaded M10x40mm (or was it 50mm? can't remember), so if i was to do it again i'd buy M10x40mm (or 50mm...) and just cut it to length.

500gls · Post by **500gls** » Mon Apr 05, 2010 4:44 pm

has been a while.

sourced 2 pretty good 915 transmissions and opened them up and found one with a hairline crack and replaced the housing and resealed and closed.
Both transmissions where pretty good and nothing was in need of replacement.
so now we have 1 rebuild 901 and 2 checked 915 transmissions.
the best 915 will go onto the car but needs to be cleaned first.

here is the family car full with all the stuff ready to be brought to the mechanic.

teardown of the transmission :

here you can see the crack, it's a place where most cracks are if there is any, enourmous torque is in between the 2 holes.

here is a view of where we are now:

Mike · Post by **Mike** » Mon Apr 05, 2010 5:39 pm

looking good, beautiful colour!