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smahaley
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update: new crossmember installed!
Technical Rusty bits - suspension
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Technical
Rusty bits - suspension
update: new crossmember installed!
Progress, something to hang those wishbones from.
Progress, something to hang your hopes on... 
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smahaley
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ha ha!! Yes indeed - all I have left to do on the front end is fabricate the collar for pressing the last bushings in on the lower arms.. then on go the new shocks and my lovely sanded and painted springs…Progress, something to hang your hopes on...
Well done, , that's a big step forward .
Might I suggest that while the engine is still out, you have great access to check the steering box and idler arm unit (if you haven't already done so).
The steering box oil can be checked via the small filler plug (8mm square iirc).
You could also see if any adjustment is needed on the st. box (screw on top of lid with locknut (22mm iirc) - the adjustment process should be covered in one of the shop manuals.
Doing this with the steering track rods disconnected makes it easier to check you've no binding after adjustment. I've found a small adjustment was beneficial on older cars that probably never had any previous attention (it's awkward to access with engine etc. in situ).
It might be possible to suction out some of the old oil via the filler/level plug but I wouldn't recommend removing the top cover (you'd need a new gasket) or indeed the steering box to empty the oil, not worth upsetting things.
Your idler box is the best one to have on a Fiat 124, being as it's hydraulically damped (many just have the rubber bush in torsion type).
The oil level can be checked via the centre plug on the cover/lid (13mm iirc). I usually renew the oil by removing the top cover (screws are 6mm allen key iirc and they're usually very tight), suction out old oil, flush, refit cover and top up with oil.
I'm certainly not suggesting you remove the idler box to 'service' it, doing a partial oil change in situ should be just fine and a lot better than just ignoring it as many people seem to do.
Afaik, normal gear oil SAE 80 or 90 should be suitable for both steering and idler boxes.
, that's a big step forward .Might I suggest that while the engine is still out, you have great access to check the steering box and idler arm unit (if you haven't already done so).
The steering box oil can be checked via the small filler plug (8mm square iirc).
You could also see if any adjustment is needed on the st. box (screw on top of lid with locknut (22mm iirc) - the adjustment process should be covered in one of the shop manuals.
Doing this with the steering track rods disconnected makes it easier to check you've no binding after adjustment. I've found a small adjustment was beneficial on older cars that probably never had any previous attention (it's awkward to access with engine etc. in situ).
It might be possible to suction out some of the old oil via the filler/level plug but I wouldn't recommend removing the top cover (you'd need a new gasket) or indeed the steering box to empty the oil, not worth upsetting things.
Your idler box is the best one to have on a Fiat 124, being as it's hydraulically damped (many just have the rubber bush in torsion type).
The oil level can be checked via the centre plug on the cover/lid (13mm iirc). I usually renew the oil by removing the top cover (screws are 6mm allen key iirc and they're usually very tight), suction out old oil, flush, refit cover and top up with oil.
I'm certainly not suggesting you remove the idler box to 'service' it, doing a partial oil change in situ should be just fine and a lot better than just ignoring it as many people seem to do.
Afaik, normal gear oil SAE 80 or 90 should be suitable for both steering and idler boxes.
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smahaley
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Thanks, @124BC1 - I look forward to checking into the steering and appreciate the guidance.Well done,
Might I suggest that while the engine is still out, you have great access to check the steering box and idler arm unit (if you haven't already done so).
View attachment 483772
The steering box oil can be checked via the small filler plug (8mm square iirc).
You could also see if any adjustment is needed on the st. box (screw on top of lid with locknut (22mm iirc) - the adjustment process should be covered in one of the shop manuals.
Doing this with the steering track rods disconnected makes it easier to check you've no binding after adjustment. I've found a small adjustment was beneficial on older cars that probably never had any previous attention (it's awkward to access with engine etc. in situ).
It might be possible to suction out some of the old oil via the filler/level plug but I wouldn't recommend removing the top cover (you'd need a new gasket) or indeed the steering box to empty the oil, not worth upsetting things.
Your idler box is the best one to have on a Fiat 124, being as it's hydraulically damped (many just have the rubber bush in torsion type).
The oil level can be checked via the centre plug on the cover/lid (13mm iirc). I usually renew the oil by removing the top cover (screws are 6mm allen key iirc and they're usually very tight), suction out old oil, flush, refit cover and top up with oil.
I'm certainly not suggesting you remove the idler box to 'service' it, doing a partial oil change in situ should be just fine and a lot better than just ignoring it as many people seem to do.
Afaik, normal gear oil SAE 80 or 90 should be suitable for both steering and idler boxes.
As for update:
I *finally* got the new pivot bars and bushings installed. It was a jumble of methods - but I did find that an appropriately sized socket could rest on the outer flange of the bushings and with some counter support and Thor’s favorite pastime (hammering) everything came back together.
Another step closer..
Meanwhile: I decided to clean up the brake discs to see what was what. I’ve changed a fair number of brakes in my earthly time, but have not seen a disc so deeply, profoundly scored as the one below:
So… to the question of new rotors or not, I say NOT. Not for the moment. I have more primary concerns about, you know, will the damn thing run. I can always put new brakes on after I have everything else in working order…
Side note: there is effectively zero wear that I could discern on the rotors. I think they were not used very much, as the car did more leaf collecting than turn-making.
I agree brake disc/rotors look salvageable and once in regular use will clean up even more. Obviously new ones are best, but I doubt if efficiency will be much affected once bedded in again with new pads.
I was going to say I would put the ball joint bolts down through as they may foul the suspension on turning steering on the wishbones, but I see the wishbone is upside down.
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Sorry to be the bearer of bad news, but.....
Lower balljoint is fitted the wrong way around in the lower A arm,
top pic (arm is upside down) shows (arrowed) witness marks of where old balljoint was fitted,
bottom pic shows old balljoint still installed (arrows show it's mounted underneath the bottom A arm, arm is upside down in pic).
I did include a caution about fitting the balljoint the correct way around in the arm....
P.S.
If I was doing this job, I'd have used shorter bolts or else shortened the bolts (leaving approx. 2 threads remaining outside the nyloc/nylok nuts).
I prefer to shorten the bolts before fitting, this allows me to file a nice crown on the cut end of each bolt, and remove the 1st 1/2 thread to leave a nice lead-in so the nut will engage easily, then touch in the cut end with some silver paint to prevent corrosion.
I'd also paint those balljoint bodies and metal parts of the suspension bushes to prevent corrosion if you don't like black or silver, you could use a clear lacquer to prevent corrosion in future.
I'd also drill and tap those balljoints to accept a grease fitting (nipple or zerk), so that they can be lubed in future.
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The brake rotors (discs), although quite heavily rust-pitted, should be ok to use if cleaned up some more, paying particular attention to removing any hard scaly type rust in the inner circular area that is swept by the brake pad - hard rust here can prevent the new pad bedding in properly, may even cause tapered wear. (i.e. new pad material can't cut through the hard rust scale, so tilts as it wears).
I used to 'refresh' used brake discs (rotors) before fitting new pads using medium emery cloth/tape, basically just taking the shine off the rotor surface, not removing metal or leaving big scratches. Powered wire brushes tend to remove surface rust then polish whatever rust is left and don't cut through any hard scale. I wouldn't recommend using a powered sanding disc or flap wheel (I've seen discs/rotors ruined by doing this).
Others may have suggestions on more modern methods of cleaning up the rotors without causing damage.
As regards the deep scratch/score on what I assume is one of the rear brake rotors, I'd check to see if there is anything that possibly could have made contact at this particular radius, (inner face of rotor, next to axle?) possibly something hard caught in the groove in the friction pad material?
If the brake rotors seem to have almost no wear (rotor thickness when new is nominally 10mm so check your's) I wonder if the brake pads might also be re-used? If friction surface looks good (not mouse-eaten or crumbly) and there is no separation between friction material and backing plate, (due to age or corrosion) they might be fine to use. If doing so, I'd give them a clean up using coarse emery paper/cloth (just bust any glaze) and clean, then lube the mounting ears before refitting. Others may disagree...
), although quite heavily rust-pitted, should be ok to use if cleaned up some more, paying particular attention to removing any hard scaly type rust in the inner circular area that is swept by the brake pad - hard rust here can prevent the new pad bedding in properly, may even cause tapered wear. (i.e. new pad material can't cut through the hard rust scale, so tilts as it wears).I used to 'refresh' used brake discs (rotors
) before fitting new pads using medium emery cloth/tape, basically just taking the shine off the rotor surface, not removing metal or leaving big scratches. Powered wire brushes tend to remove surface rust then polish whatever rust is left and don't cut through any hard scale. I wouldn't recommend using a powered sanding disc or flap wheel (I've seen discs/rotors ruined by doing this).Others may have suggestions on more modern methods of cleaning up the rotors without causing damage.
As regards the deep scratch/score on what I assume is one of the rear brake rotors, I'd check to see if there is anything that possibly could have made contact at this particular radius, (inner face of rotor, next to axle?) possibly something hard caught in the groove in the friction pad material?
If the brake rotors seem to have almost no wear (rotor thickness when new is nominally 10mm so check your's) I wonder if the brake pads might also be re-used? If friction surface looks good (not mouse-eaten or crumbly) and there is no separation between friction material and backing plate, (due to age or corrosion) they might be fine to use. If doing so, I'd give them a clean up using coarse emery paper/cloth (just bust any glaze) and clean, then lube the mounting ears before refitting. Others may disagree...
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I checked back to when you reported on fitting the new balljoint and bushes to the top A arm (post#109) and this upper balljoint seems to be fitted correctly. (pic shows arm upside down.
One way to decide on which side of an A arm to install a balljoint, is to determine which side of the arm takes the load applied through the balljoint, the arm should take the load, the bolts shouldn't, they just hold the balljoint to the arm i.e the bolts are not carrying the load.
Another way is to pay close attention to the 'shop manual especially the sectional diagrams that show how things are put together (or should be
)On the Fiat 124 Spider (and Coupe and Sedan) the top balljoint fits under the top A arm, the bottom ball joint fits under the bottom A arm.
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smahaley
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Poop! I shall refit them!! Thank you!
I bet you're glad you fitted the new balljoints using bolts (and not rivets as per original)...
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smahaley
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Thanks for the words of wisdom re: brakes.
Speaking of which: I discovered a few things.
1) the brake compensator valve boot retainer (looked like an aftermarket zip tie) had failed
2) the brake line connections were impossible to undo (even with heat - which threatened to set things afire - and penetrating oil )
3) after I cut the brake lines off and lowered the valve with bar, SAND (or something akin) poured out of the torn boot.
No. Not an April Fools joke.
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smahaley
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So: I am now at the point of reassembly so will leave close this thread up with the above image of the rear axle and reassembled brakes ready(ish) to the reacquainted with the vehicle (along with the repainted springs and new shocks).
I have other surprises to share but will do so under a new heading, as “Rusty bits - suspension” no longer really applies.
Onward!
Your going to need a cool new title for your next thread...Man your going to be taking that first drive this summer! Great work!
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smahaley
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Good day, sir..Well done,
Might I suggest that while the engine is still out, you have great access to check the steering box and idler arm unit (if you haven't already done so).
View attachment 483772
The steering box oil can be checked via the small filler plug (8mm square iirc).
You could also see if any adjustment is needed on the st. box (screw on top of lid with locknut (22mm iirc) - the adjustment process should be covered in one of the shop manuals.
Doing this with the steering track rods disconnected makes it easier to check you've no binding after adjustment. I've found a small adjustment was beneficial on older cars that probably never had any previous attention (it's awkward to access with engine etc. in situ).
It might be possible to suction out some of the old oil via the filler/level plug but I wouldn't recommend removing the top cover (you'd need a new gasket) or indeed the steering box to empty the oil, not worth upsetting things.
Your idler box is the best one to have on a Fiat 124, being as it's hydraulically damped (many just have the rubber bush in torsion type).
The oil level can be checked via the centre plug on the cover/lid (13mm iirc). I usually renew the oil by removing the top cover (screws are 6mm allen key iirc and they're usually very tight), suction out old oil, flush, refit cover and top up with oil.
I'm certainly not suggesting you remove the idler box to 'service' it, doing a partial oil change in situ should be just fine and a lot better than just ignoring it as many people seem to do.
Afaik, normal gear oil SAE 80 or 90 should be suitable for both steering and idler boxes.
I’ve just got around to checking the steering box and idler assembly. I need to procure the correct socket to check oil on the steering box… however I did remove the top of the idler box and to my surprise (?) it was all packed with bearing grease. I noted your comment about filling with gear oil so consulted Pininfarina and Haynes and both gave zero (!) info on maintaining the idler inner workings.
Should I just leave it be?
Grazie
Just for fun I asked A.I. the question for my year (79) ,And it came back with sae 90 weight gear lube..but a.i. isn't always correct , so curious what the experts say, will consult my manuals as well
Socket for filler plug on the steering box? Iirc, it's an 8mm square (8mm = 5/16 in.). I've never had an 8mm size square socket. Some alternatives:-
You could use 2 x 8mm open end wrenches positioned opposite each other to unscrew the plug.
I've used to use a 5/16 in. square brake adjusting wrench as used on old British cars.
Afaik, 5/16 in. square is a size used in refrigerator work?
I once made my own 8mm sq. wrench - drilled an 8mm hole in a length of 1/4 in. flat bar then filed the round hole into a square.
There may even be a bi-hex (12 point) socket of a size larger than 8mm that will fit an 8mm square sufficiently well to loosen the plug.
(I recall that e.g. a 15mm bi-hex socket will fit the 13mm square head filler plug used on the smaller old Fiats e.g. 500, 600, 850.)
The idler box was usually ignored in servicing. Checking/topping-up the steering box oil is mentioned in the Owner's Handbook - it stated SAE 90 gear oil.
As regards topping-up? why? unless it was leaking? I vaguely remember that the oil was to be topped up to 8mm below the filler plug opening, can't remember if this was for the st. box or the idler box.
I do believe in leaving space for liquids to expand either due to increase in surrounding air temperature (idler box is close to the exhaust system on lhd cars; steering box is close to the exh. on rhd cars) or being heated in operation - fluids forced through a restriction will heat up and therefore expand -try feeling a cars 'shock absorbers' (suspension dampers!) after a run - be careful you don't burn your fingers!
If the oil has no space to expand into, it will find a weak spot, likely the oil seal in this case. Some units containing oil that will heat up, incorporate a breather, the 124 trans. has one on the bellhousing near the main casing, the rear axle casing has one also - these breathers should be checked if an oil seal fails.
People on various forums recommend using grease instead of gear oil in the steering box and idler box - I suspect this is to try to prevent oil leaks. Would you install grease in your shocks as a solution if they were leaking oil? I don't think so.
The correct solution for oil leaks is to strip and rebuild the units, replacing any worn bushes/bearings (so shaft's don't wobble around and impair the seals operation) and then fit new seals.
Steering box rebuilds can be very costly (if you can source the parts), so-called rebuilt/overhauled boxes supplied on an exchange basis depend on the ability and integrity of the person doing the rebuild...
I've seen mention that internal parts are not available for the idler box but that the oil seal is still available.
Some resort to fitting the other type of idler box that was used on various Fiats (+Ladas), i.e. the non-hydraulically damped unit that has simple bushes.
This I regard as a retrogressive change - Magazine Road-testers, back in the day, commented on how much nicer the 124 Sport Coupe and Spider steering was due to having needle roller bearings on the st. box output shaft and a hydraulically damped idler box.
There's another thread currently running on here by S854 ("Don't hate me..." Apr 16, 2026) who has bought an early restored 124 Spider on an auction site, he supplied a link to the site and opening this site and clicking on 'Comments', revealed various Q's and A's about this car - someone from Fiat Plus (supplier of genuine Fiat parts) / C.Obert & Co. provided current info re the idler box/availability of parts/ changing to bush type idler box etc.
Here's a page from FiatPlus concerning a 'rebuilt' Idler box, it mentions the box being filled with grease and the internal wings being cut back.... :-
TLDR?
Q. Should I just leave it be?
A. Yes.
I agree with @124BC1 90 gear oil. People who put grease in place of oil are trying to cover up a problem, much the same as tractor joints (the chrome balls) on LandRover front ends, we always fitted new oil seals on good undamaged tractor joints and made sure the shims of the suspension were correct so joint was central with no excess play. That way the gear oil stayed in the joint doing it's job.
