Lancia Motor Club

Model Technical and Interest => Fulvia => Topic started by: davidwheeler on 23 October, 2012, 02:16:22 PM



Title: Brake servo
Post by: davidwheeler on 23 October, 2012, 02:16:22 PM
Next problem.  The servo on my series II Sport 1600 is not functioning.  Omicron do not have recon. kits but Cavallito sells a diaphragm and various folks on Ebay sell recon. kits for series IIa Girling servos as fitted to various British cars of the 60s.  Can anyone tell me what type of servo is fitted to my car (apart from Girling, that is!)?  The alternative is to fit a servo and master cylinder from another car - has anyone done this?  I have asked Amadei for a quote for a complete servo and await with bated breath for the shock.


Title: Re: Brake servo
Post by: lancialulu on 23 October, 2012, 05:26:58 PM
Bonaldi Italy. Dont know they come apart. Have you tried second hand? Alternatively try Roberto at Spitline! http://spitline.com/scheda.asp?id=10644 (this is the part - seems on an exchange basis but not expensive)....

Tim


Title: Re: Brake servo
Post by: davidwheeler on 02 November, 2012, 10:55:06 AM
Yes, also http://lancia.cc/?page=article/catalog&catalog=Catalogue%20Fulvia.  Trouble is, international carriage for return (2.6 Kg) costs 60!  Anyone know a way round that one?


Title: Re: Brake servo
Post by: Parisien on 02 November, 2012, 11:08:46 AM
http://www.parcel2go.com/?ad=priceled&gclid=COy2x_SDma8CFYpjfAodHCNO1w

Could try these guys

P


Title: Re: Brake servo
Post by: ncundy on 02 November, 2012, 12:46:53 PM
I don't recall repairing the servos was any great difficulty. It's a while since I've done one but there's not a lot to them. As I recall the only tricky bit is spliting the chamber without the spring flying out. I think it was a two person job with the case held in the vice, one steadying it whilst the other turned one half until the detents had unlocked.

Once apart you need to check it for rust as water collects at the bottom and can cause pin holes, although failure is almost certainly the diaphram splitting. Clean it, a good coat of etch primer and a good top coat inside and out then it should be fine.

Neil


Title: Re: Brake servo
Post by: Parisien on 02 November, 2012, 01:13:16 PM
I don't recall repairing the servos was any great difficulty. It's a while since I've done one but there's not a lot to them. As I recall the only tricky bit is spliting the chamber without the spring flying out. I think it was a two person job with the case held in the vice, one steadying it whilst the other turned one half until the detents had unlocked.

Once apart you need to check it for rust as water collects at the bottom and can cause pin holes, although failure is almost certainly the diaphram splitting. Clean it, a good coat of etch primer and a good top coat inside and out then it should be fine.

Neil

I think a DIY post with photos would be good on this Neil/David.......

:)


P


Title: Re: Brake servo
Post by: davidwheeler on 17 November, 2012, 02:42:04 PM
I have had quite a chat by email with Felix Furtak at

http://lancia.cc/index.php

who are based in South Africa.  They can supply exchange units but the cost of transport to SA from UK is excessive so I am trying a UK firm (will report back).   He has been very helpful and attentive and it is a shame I cannot do business with him.  They have a good selection of spares for all older Lancias and could be worth a look.

I don't feel at the moment up to doing it myself and where would I get a diaphragm anyway?  Need to get on and do other Lancias so this time I will buy someone else's time!


Title: Re: Brake servo
Post by: davidwheeler on 01 February, 2013, 01:49:47 PM
Just had the servo rebuilt by J&L Spares of Rochdale http://www.jlspares.com/brakeparts.htm  for 210 including vat and delivery.  It looks like new, has clearly been stripped cleaned, rebuilt and even replated.   Nice people to deal with and none of the complication and cost of sending to Italy.


Title: Re: Brake servo
Post by: davidwheeler on 05 March, 2013, 05:56:31 PM
Put it on and all was well for some 20 miles.   Then the brake pedal travel became minimal, thought "Ah, no air in the brakes, fine"  Then after a few more miles, while overtaking a tractor, the brakes came on of themselves, harder and harder and I had to stop (safely past the tractor but a bit embarrassing nonetheless).  I slackened the joints of the pipes at the master cylinder to release the pressure and re-tightened and went home on the handbrake (who needs brakes anyway?).   This morning put her in the garage and started her up and tried the brakes a number of times and they felt totally normal.  Anyone any ideas please?   The chap from J&L spares did not think it was likely to be the servo (but offered to retest it anyway).


Title: Re: Brake servo
Post by: lancialulu on 05 March, 2013, 06:33:16 PM
check the actuating rod as the length can be sensitive and provide the symptoms you describe. Never had this my self but have heard lf it on Fulvias.....

Interest ingly I reversed my HF out of the Garage after a longish rest over winter and back down the drive and the brake pedal went to the floor when trying to stop.  Pulled handbrake on and pumped the pedal a couple of times a it now feels like normal.


Title: Re: Brake servo
Post by: nistri on 06 March, 2013, 12:41:16 PM
I agree with Tim: even a very minor change in the actuating rod length can produce the problem you had. This is manifested when the underbonnet temperature goes up and induces a slight increment in the overall length enough to block the brakes. You will have to reset the system by reducing the rod extension by 2-3 mm. However, it can be a matter of trial and error. Andrea


Title: Re: Brake servo
Post by: Neil on 06 March, 2013, 02:14:41 PM
I have experienced this problem in a friend's S2, especially on warm days when the car will become virtually undriveable as you destroy the front brake pads, let the car cool down (several hours) and the brakes free off or release the pressure on the master cylinder, he has rebuilt the master cylinder, rebuilt the calipers, replaced the front flexible pipes to no avail.  Another Fulvia driver in the UK had the same problem, they read of a similar problem with another make of car and make some adjustments and the problem has not re-occurred since shorting the rod length to the top of the pedal.

I have just sent my master cylinder and servo to be reconditioned by J&L, the parts arrived today and will carefully measuring the rod before refitting to the car as per the manual's recommended length.


Title: Re: Brake servo
Post by: ColinMarr on 06 March, 2013, 06:21:27 PM
I have experienced this as well. The early warning of the brakes about to bind-on being less and less free movement of the pedal. Shortening the rod by half a turn of the adjuster solved the problem for me. And fixing it lying upside down with your head in the footwell in the dark and in the rain is such fun!

Colin


Title: Re: Brake servo
Post by: the.cern on 06 March, 2013, 10:10:51 PM
Colin, you get all the fun !!!!!!!!

There is nothing like necessity to force the issue, in your case dark and rain were not sufficient to prevent you  from successfully addressing the issue.

This, 'I will succeed' attitude is I feel sure what binds we of the LMC together. Well done !!

                                     Andy



Title: Re: Brake servo
Post by: davidwheeler on 07 March, 2013, 10:10:28 AM
At least I was able to do this in the garage in the dry.   Seems logical, have done same, brakes now come on at a comfortable half pedal and so far so good.  Thank you Gentlemen!


Title: Re: Brake servo
Post by: davidwheeler on 25 June, 2013, 11:03:09 AM
Ah, but it was not so.  They continued to bind and I had to slacken off to an absurd degree and never seemed to be able to get the sponge out of the system.   Finally I looked at the front brake pads.  I took them out and the pads (scarcely worn) promptly fell off their backing plates!   I have skimmed the discs and fitted new pads and the brakes at last feel as they should and I have been able to lengthen the operating rod back to where it should be.  'Tis what happens when the car has been off the road for a bit I suppose or maybe they got pulled off in a binding on episode.   Whatever, there is always something to surprise us.


Title: Re: Brake servo
Post by: nistri on 25 June, 2013, 12:35:32 PM
Do you know the make of these pads? Andrea


Title: Re: Brake servo
Post by: davidwheeler on 26 June, 2013, 01:42:07 PM
Not off hand, they came from Omicron but have been in place a number of years.    I guess they got damp.


Title: Re: Brake servo
Post by: phil-m on 26 June, 2013, 07:01:30 PM
I would not be so generous, even if they got damp and had been stood the pads should not have seperated from the backplate.


Title: Re: Brake servo
Post by: ben on 16 July, 2013, 05:52:51 PM
Further to Neils comment that overhauling the servo is not too difficult this is the special tooling I have just used to get mine apart.


Title: Re: Brake servo
Post by: ben on 16 July, 2013, 06:27:00 PM
Also while on the subject does anybody know if the banjo connection to the vacuum chamber is supposed to be a one-way valve.
Mine was completely blocked which would obviously mean the servo wasn't doing much. It also explained why there was a large quantity of brake fluid trapped in the servo vacuum chamber which would normally get sucked into the engine. The rubber diaphragm was in good condition so I have re-used it.
I have cleaned out the connection which seems to have quite a devious baffle inside it but it now appears to be able to flow in either direction.

Incidentally I found the overhaul of the master-cylinder to be a more challenging undertaking.
The screws retaining the reservoir were very reluctant to come out. Three of them sheared off !
Then the big plug in the end of the body required the application of heat to the alloy body before it would come undone.(32mm spanner and 3 foot lever arm!!!)
Also note, when reassembling feed all the bits in from the plug end to minimise the chance of damaging the nice new seals that Omicron supply.And don't forget the aluminium washer that the plug seats down on. 

Next job is to attack the calipers!


Title: Re: Brake servo
Post by: JohnMillham on 16 July, 2013, 08:13:49 PM
Is there a simple way to reduce the size of the photographs, so I can see the whole photo in stead of just one corner of it?
Regards, John


Title: Re: Brake servo
Post by: davidwheeler on 17 July, 2013, 09:19:01 AM
Use this program
http://www.obviousidea.com/windows-software/light-image-resizer/
David


Title: Re: Brake servo
Post by: davidwheeler on 17 July, 2013, 09:21:52 AM
And yes, it is a one way valve and if it is blocked the servo does not work.   The object is to accumulate vacuum in the chamber, if the valve does not work vacuum is lost when you accelerate.   If your is now two way you will need to replace it.


Title: Re: Brake servo
Post by: ben on 17 July, 2013, 02:53:14 PM
Just as I suspected.I will now have to see if I can get that apart!

I don't know why the pictures came up oversized John.
On my PC you can click on the blue titles at the bottom of each picture which gives you a box at the bottom of the screen on which to click again and they then appear at the correct size


Title: Re: Brake servo
Post by: lancialulu on 17 July, 2013, 04:48:36 PM
I flushed mine out and after a while it seemed to work so I put it on the car 7 years later it still is working....Difficult to open up as a peened over assy??


Title: Re: Brake servo
Post by: ben on 17 July, 2013, 07:30:37 PM
Even after an overnight soak and much blowing and squirting  I was not happy with it so bit the bullet and opened it up.
The alloy was too brittle to "unpeen" so I filed away the peened over bit and have exposed the innards which I can now clean properly. It was full of a dried out brown deposit which presumably is a residue from brake fluid. (The car has not run for about 20 years)
I think it should hold back together with a little araldite and a small clamping ring.

Hopefully the picture of the innards will be the proper size this time!       


Title: Re: Brake servo
Post by: lancialulu on 18 July, 2013, 07:09:13 AM
Another bit of beautiful engineering!!

Photo still large on forum though.....(it is fine if clicking on the blue file name)