Getting ready for 3ma10

[Thotos]

Yes (while touching wood) it seems to be a successful transplant. In fact I took the car for a longish drive afterwards and everything seems fine. It even seems quieter than the old diff used to be before it broke.  The back axle on my old 'spares' car looked worse for wear although I'm sure some stiff wire brushing and a coat of black paint would have made it look as good as new. But my current car has a rear disc conversion and it would have been a lot of extra work to transplant the disc conversion as well as all the suspension over so I decided to follow Nick's advice and swap over just the pinion and diff. But it took a lot more than an hour and a half! The pinion needs the right amount of shimming to allow it to turn smoothly without being too loose allowing for movement. There's a long spacer (which seems collapsible) between the two pinion bearings and the 'new' pinion had an extra shim behind this while the old one didn't. The two 'collapsible' spacers were not the same length so there was a bit of trial and error using the different size spacers with and without the shim to get the pinion just right. Similarly, the diff unit has a spacer shim either side of it to position it against the pinion. Move the crownwheel further to the right by fitting a larger shim on the left and you get it closer to the pinion or fit larger shim to the right and it moves the crownwheel to the left and away from the pinion. We had 4 different sized spacer shims from the two axles and I think we had the diff in and out about 6 times before we decided we had the correct combination of spacer shims to give the correct mesh with the pinion. And of course the rear disks and associated calliper brackets had to be removed to undo the driveshaft bolts and draw the shafts out. Luckily the new replacement Brembo disks I ordered earlier in the week arrived yesterday so I now also have new disks and pads fitted with a very noticeable improvement in braking. So all in all a very successful albeit very long day today.  

My thanks to Jason for the emergency sugar fix and to John for his help and of course to Mark for his invaluable advice and assistance.

[simon131]

That's good news Theo. I bet you ache this morning though!

Need to get my Arbie sorted now. Found some new suspension via a member of this forum and hope to collect very soon. The car will need a little attention for the MoT so hoping to get that done at the same time as the swapping of suspension components.

[theredx19]

Well Theo you are meant to change that collapsable spacer as it is for preloading the pinion bearings but I take it you used some engineers blue so you dont suffer another chocolate diff melt down. But do get a lying down board to save you from the damp concrete as your old limbs will thank you as you could be needing a 131 with an auto box and power steering as your limbs will be fooked with the damp getting in 

[Thotos]

Well Theo you are meant to change that collapsable spacer as it is for preloading the pinion bearings

Well that's what we figured but we only had two used spacers of which one was too short and the other too long.  The original plan was to swap axles so we wouldn't have to disturb the diff. 

If you look at the photo you'll see a nice pink blanket for lying on as well as a board although there was a lot of crawling around on concrete and even wet ground to get the diff out of the 'spares' car. Unfortunately Mark's workshop was rather full with two Alfas and two Lancias (one of them being my Gamma) so rather than rearrange the cars to get the 131 inside we decided to work on it outside. It was only meant to take an hour or so anyway!   

[eugene]

Just wondering,are the series 1 back axle prone to the disease that Theo's one has,or is it just the sport axle suffers from this .Eugene

[Thotos]

That's a good question Eugene and one that I can only guess at the answer. I believe the rear axles are the same between series 1 and series 2 (and possibly series 3?). So when the Fiat 131 was originally designed the axle had to cope with a 1300 and 1600 OHV engine of limited power. Fiat then started putting twin cams in the 131 with the Sport having 115bhp and loads of torque and the poor diffs just don't seem able to cope.    I never had any problems with the diff on my Series 1 1600 131S (which I had for many years and many tens of thousands of miles including several drives to the Continent and even a drive to Turin and back). I also never had any problems with my Series 2 1600CL (now in Ireland) although I only did limited mileage in the two years I owned it. But my Silver 131 Sport had 3 diff changes while I owned it; they only seemed to last about 60,000 miles if lucky or less if not. And now my current Sport is on it's second diff since my ownership. In all cases the problem was with the pinion loosing its teeth and never with the crownwheel or diff unit itself. So to answer your question, I'd say this problem is limited to the Sport or possibly the larger engined cars in the 131 range. Anybody out there know different or know how long the diffs last in the 2 litre Supers?

[sid131]

Well done Theo hopefully it will last a good while, i only took me that long to change the diff & pinion i just bolted in the one from the other axle & it worked fine for a long time, i see you had limited space to work in is that a back alley garage? i have access to a lift & i also have huge axle stands  for my oldish frame to get under the car, is the bloke that did it expensive?

[Thotos]

Mark has a fully equipped workshop (www.ItalianRaceServices.co.uk) with a full size hydraulic ramp but as I said his garage was full with other cars so decided to do the work in his driveway. It was worse than that getting the diff off my 'spares' car which is sitting in a field behind Mark's garage! We did the work together or I did most of the hard work with Mark's invaluable advice and assistance. I wouldn't say he is expensive but I also wouldn't say he is cheap in case he is reading this and decides to put up his prices!   He is still restoring my Gamma and that's costing me a lot of money!  

I used the 131 to get to the office this morning to see how it copes with London's stop-start rush-hour traffic and I am pleased to say that it behaved admirably with a still very quiet differential.  

[sid131]

well his website seems to just have the one car think its your lancia Theo but love the address 199 pound lane bet you would need more than that in yer wallet to go there??

[Thotos]

his website seems to just have the one car think its your lancia Theo

There's also the library photos of the 131 Abarth and 124 Spider  But yes you are right it is my Gamma shown there. I did Mark's website (hence the logo  )  years ago about 1996/7 and all I had from his work were the photos of my Gamma.  You are right about the address though and yes I have spent a lot more than that with Mark over the years.

[sid131]

ll i wish i could get the sort of money he charges per hour, i am here in Ireland with all the tools & experience for restoring older cars & no work at the moment so very frustrating sometimes, today i have only 1 job for tomorrow a new clutch in a 98 gsxr 750, tried to get away from the bikes but beggers cant be choosers, would it cost much to get a proper website set up Theo?

[Thotos]

Mark has the opposite problem: too much work and he can't cope with the demand. And it is a problem as he's had my Gamma for over a year now and there's still no end it sight. And I am supposed to be going to Germany in the Gamma in April!    At the moment Mark has 3 cars in his workshop undergoing full restorations, a 156 having a full engine rebuild, a 131 waiting for a restoration, a 131 Abarth replica (sort-of) with turbo engine waiting for major mechanical work, a 75 waiting for major bodywork plus several other smaller 'projects' including his own Ford Anglia rebuild (which will have a Fiat twin cam in it). He was actually telling me last week that he is thinking of having new bigger workshops built to house all these projects but I keep telling him he needs to either get an assistant or start turning work away (which he had to do recently) otherwise he'll never get my Gamma finished!     He did have an assistant for a while (unemployed professional welder friend) whom he got to do some work on my Gamma and now it seems Mark decided to re-do most of his work  "He is a good welder but lacks finesse and that won't do in my workshop" he said to me. 

I've sent you a PM about websites.  

[sid131]

i like what he said lacks finesse thats the way i feel about some work i have to redo, he must be good then this mark well he has some hard restorations on his hands!

[paulcas]

".......................I'd say this problem is limited to the Sport or possibly the larger engined cars in the 131 range. Anybody out there know different or know how long the diffs last in the 2 litre Supers?

I had my 131 Sport for 16 years and needed three replacements - only did 60k miles in it! 

[jasonh131]

Is it something to do with wheelspining from standing starts  i know i had that problem ,and when you get a good one going you just can't help prolonging it and pendulming all the way down the road