Alfa Romeo Owners Club of Australia Forum

Technical => 116 Series (Alfetta Sedan/GT/GTV & Giulietta Sedan) => Topic started by: Sam on July 05, 2011, 11:56:23 PM

Title: Twin spark gearbox on 3 litre 75
Post by: Sam on July 05, 2011, 11:56:23 PM
Hi everyone ...
I'm having a problem that is really causing me some grief ...

Background
The gearbox on my son's 3ltr 75 was a mess - gears crunching, bearing noises, etc
His clutch went recently and given the condition of the box, we thought while the clutch was being fixed, we should drop the box and rebuild it too.
The average quote he got was $2000 to $2500 plus a few months wait for it to be done.
Given he has a new baby on the way and funds a little tight, as a short term solution, I  offered him my spare Twin Spark gearbox until he gets around to rebuilding the 3LTR one.

while installing the TS box, we encountered 3 main issues.

1)   The wheel hubs have larger bolts on the 3ltr, so I also gave him my spare Twin Spark A frame.
2)   We could not use the TS clutch assembly because the  donut flanges are smaller than the 3ltr ones, therefore we used the 3ltr clutch assembly to ensure it would bolt up to the lager donuts.
3)   The 3ltr clutch is Pull type, so we had to change over the pivot pins where the thrust bearing fork pivots on.

It seems pretty much straight forward, a little bit of work, but it all seemed to go together ok.

Issue
1) We have everything bolted up and looking ok, except I can't seem to bleed the clutch slave cylinder
I tried the usual tricks, like pushing it backward, (in case there is air towards the front  of the cylinder), but it still want come hard.
I'm worried, because I can't see air coming out of the bleeder, yet the pedal goes straight to the floor and won't come up.
I did manage to get it working at one stage, maybe 80-90% expected pedal feel, but then while trying to get the last 100%, I played with the bleeder and it went flat again.
Is there something I'm missing with this?

2) has anyone else put a TS box on a 3 litre 75?


Thanks in advance
Sam
Title: Re: Twin spark gearbox on 3 litre 75
Post by: Darryl on July 07, 2011, 09:44:58 AM
Re bleeding the clutch - I've always found it a pita, no specific advice, though sorry...

Regarding swaps. I haven't put a TS box in a 3L however I have an Alfetta I'm trying to put a 3L box in. Similar issues in reverse. And I don't want to swap the A frame/hubs because I'm attached to the 4 stud hubs... There is an alternate approach (I think) to swapping the A frame, which is to swap the output shafts on the transaxle, which should (I was hoping you had gone this way to confirm) work between TS and 3L because of the (I belive) same LSD centre being in both (same shaft size/spliines). It doesn't work between 3L and Alfetta because the Alfetta shafts are smaller diameter... Ah - and I see you have been on alfaGTV6 - you proly saw my posts there too....

Not wanting to hijack - but if anyone has TS output shafts from an otherwise r**ted or only good for parts transaxle I'd be very interested....... See wanted section....

Title: Re: Twin spark gearbox on 3 litre 75
Post by: bteoh on July 07, 2011, 03:37:01 PM
Hi Sam,

I had the same problem after changing the clutch master cylinder on my 75 3.0 v6. Tried vacuum bleeding from the slave cylinder but to no avail. Had to unhook the line from the slave cylinder and blow compressed air in reverse and that blew out all the crude from the line. Be carefull to get someone to put a cloth around the other end so as not to get brake fluid all over the engine bay.
Good luck with that.
Cheers
Brian
Title: Re: Twin spark gearbox on 3 litre 75
Post by: alfa duk on July 07, 2011, 05:50:08 PM
 With the bleeding of the clutch i had a similar problem and it was a simple fix. When you bleed the slave make sure that you rotate it so the bleed nipple is at the highest point. Hopefully its that easy. Doug
Title: Re: Twin spark gearbox on 3 litre 75
Post by: Sam on July 07, 2011, 06:51:18 PM
Hi everyone - thanks for your comments, some good ideas for me to try. I'll see how I go
thanks
Sam