Conaero's Spider Rebuild

[lisknik]

I'd rust proof the pan while you are there mate

 

[conaero]

I'd rust proof the pan while you are there mate

Already done mate.

 

[conaero]

UPDATE:

Well I finally got the rear end fully pollybushed, 14 in total. Once you get the hang of manipulating the suspension with jacks its pretty easy, just takes time.

I elected not to attempt to remove the old bushes, I farmed that out.

Also painted the hubs and did a service so she is lurking in the garage fully done, waiting for the Spring



I had already had most of the parts previously blasted and powder coated but I went belt and braces and gave them another coat of stone chip.

Many have complained about the rear end polybushing making the car too stiff, I am having none of it, you cant tell, just everything feels tight now. Also did the upper balljoints and droplinks too.

Happy to report, it now does not squeak over every bump and the rear wheels that had 3 degrees negative camber are now sitting as they should and the whole car drives and handles much better.

 

[StuartW]

Good work Matt, now make sure you don't mix up your bushes with your cat food ...

 

[lisknik]

Good work Matt, now make sure you don't mix up your bushes with your cat food ...

I was wondering i he was using cat food instead of grease tbh

 

[conaero]

That's my expensive diet food!

 

[lisknik]

That's my expensive diet food!

You eat cat food!!!!

 

[conaero]

The Spider is now taxed/and insured. The MOT needs doing in the Spring.

I have a couple of final jobs, one is putting the badges back on. I've done the 3.2 V6 24V on the boot, just need to do the Spider boot badge and the rear quarter Pinifarina scripts and shields.

The most annoying feature now is the spongy brakes, they have never been right and although they got through the MOT like that last year, after nearly going into the back of Contigo (yes, heard them all before) I need to get this sorted.

The callipers have been stripped, painted and new seals, covers and valves fitted. Its been bled 10 times in a variety of different methods but still its mushy. On the second pump they work very well. All discs and pads are new.

I had the garage look at it and they put hose clamps on each of the calliper hoses in turn and when clamping off both front calliper hoses, the pedal was firm as it should be.

The good news here is that its not the master cylinder, servo or ABS unit and the issue is definitely with the front callipers.

The bad news is I don't know what is wrong.

I have ordered 2 new front calliper hoses and I am going to strip the front callipers again and lube the seals.

I have found a couple of interesting articles that I am going to follow to dry and resolve this irritating issue:

http://forum.alfa156.net/forum/forum_posts.asp?TID=11082&PN=0&TPN=1

http://mbworld.org/forums/c-class-w...e-pedal-feel-after-brake-pad-replacement.html

Anyone who has had brake issues with the Brembos on an Alfa, any advice would be appreciated.

 

[Swedish Paul]

Don't know about Alfa's but don't Brembos usually have 2 bleed nipples per caliper, maybe stating the obvious.

 

[conaero]

Don't know about Alfa's but don't Brembos usually have 2 bleed nipples per caliper, maybe stating the obvious.

They do yes, maybe there is air still in the calliper but they have been bled so many times its unlikely, it more of a travel thing.

 

[BennyD]

It might be the piston seals; if they stick to the pistons in the 'retracted' position they can pull the Pistons further back into the calipers. The 'slop' comes from having to push the pistons out each time you brake.

 

[conaero]

It might be the piston seals; if they stick to the pistons in the 'retracted' position they can pull the Pistons further back into the calipers. The 'slop' comes from having to push the pistons out each time you brake.

They are new, but I do feel that this is where the issue lies.

In effect, I have no air in the system, but when I press the peddle, the front calliper pistons are travelling too far, hence the need to pump them....and this would be caused by them sticking.

One trick is to make up wood plates the same thickness as the pads backing plate and cycle the pads and lube under the dustcover with WD40, Ill change the hoses, do the piston cycle and report back.

 

[CatmanV2]

Had this with the 4200 brakes. They eventually sorted themselves out

C

 

[philw696]

Never had a problem with the Italians but the Audi VW range have a sneaky little bleed nipple on the master cylinder body.
If the reservoir gets too low during bleeding you can get air in the master.

 

[allandwf]

As Benny says, I've heard of the seals flipping in the Brembos. I would possibly have thought they may weep though.

 

[conaero]

No fluid loss.

Phil, no bleed nipple but I did crack off the banjos with a pressurised system, no air, no change.

 

[conaero]

Well, today was the day I decided to tackle my Brembo 38/42 brake pedal travel on my Alfa Spider...mainly due to the fact I nearly mounted Contigo's GTS during a spirited drive in Wales over Xmas.

Whats been happening is I have referred all the callipers, discs and pads plus replaced all the fluid and bled and bled and bled but still have excessive brake pedal travel.

It went to the local garage in the end who bled it, then bled it again, and once more for luck. We know this....there is no air in the system!

What the garage did that was clever was to clamp off each flex brake pipe in turn to isolate the problem and rule out the master cylinder, servo and any other part of the system.

When clamping off the front callipers, the pedal went firm which points to the problem being 100% with the front callipers.

So, yesterday, in readiness for summer, I decided to get on with it.

I remove the front callipers, which will be taken apart again and have another set of seals and dust cover plus replace the front hoses.

So, callipers came off easy but the hoses where they connect to the brake pipe was seized solid on both sides. I use heat and the correct slotted 11mm brake pipe spanner but it still jumped and rounded off. In the end I had to cut them off which means I have to now replace the brake pipes all the way back to the ABS unit. Its not costly, got the copper kit which you bend into place for £35 delivered from http://www.automec.co.uk who were really helpful. They did not have a kit registered for the GTV 3.2 so I had to remove mine (nightmare) and measure them with a piece of string to get the length. The near side is 40" and the off side 66" with M10 fine (1.0) thread short (15-17mm) male connectors.

The difficulty is access. In the end I had to cut the longer one in 2 places to get it out and am not looking forward to refitting them. The ones going back in are copper and very malleable but I am expecting a lot of swearing and cut knuckles.

Once this is done, I will strip the callipers and replace the seals again and also adjust the over return this Brembos seem to have issues with:

The pistons in a brake caliper depend on the distortion of the D shaped seal to return them to the brakes off or resting position. When changing pads on these cars great care should be taken not to push the pistons back too far in the caliper to get the old pads out. You should just push them back sufficiently to release the old pads. If you don't do this, stiction of seals on the caliper bore can cause the piston to move forward but not bring the seal with it down the bore surface & cause the piston to over return when you release the brakes. You then need more fluid to bring the pads back in contact with the disc (rotor) which gives you a low or mushy pedal

Partially worn rear pads & new fronts leaves you with greater fluid requirement to engage the rears than the front. This unbalances the 2 circuits requiring just one light pump of the pedal to regain the ideal pedal movement or firmness of pedal. It's hit and miss depending on stiction in the rear calipers. Sometimes you get away with it & sometimes you don't. You have no idea how many cars this plagues. Mine included.

Your braking bias front to rear is correct but has nothing to do with this situation.

BTW - the term stiction comes from the shock absorber industry & describes the stick/slip action of seals on the shaft. The sames applies to the action of the D shaped cross section seal on a caliper piston operating in the bore. The D section seal looks a bit like an O Ring. If it sticks to the bore instead of sliding down the bore you suffer over return. We are talking pretty small movements here.

You are lucky you don't own an Alfa - they are chronic for doing this. Our cars don't do it as badly but it's irritating nevertheless. I would have said it was a Brembo thing but older Alfa's with Lockheed Bonaldi brakes were even worse.

Its never easy its it!

 

[allandwf]

Interested to hear the outcome once you find what the issue is.

 

[conaero]

I know Muppet is suffering the same issue on his 164.

I have had a similar but less of an issue with the 3200/4200's.

I though all of them had this initial pedal travel but when I fitted new discs and pads all round and did not push the callipers all the way back in I had a very noticeably better feeling pedal.

I also had terrible sticking with my 3200 front Brembos.

Basically, I am not a fan of Brembos. They may be painted and logo'd up and be Italian but I would not choose them and I have constantly had issues with them.

 

[2b1ask1]

I've had bikes and are suffer from balloning flexible pipes when over about 10 years old, this reason I generally change them out for braided. Hope you get it sorted quickly Matt.