GTC 4 Brake Servo
GTC 4 Brake Servo
Posted by Dr. Ian Levy
Can anyone suggest how I finish the brake servo on a GTC 4?
I think it was a yellowy galvanised/zinc finish originally, but it is mouldy/rusty/ grubby & won't clean .
I can paint it & if I do, what colour?
Thanks
Regards
Ian Levy
Can anyone suggest how I finish the brake servo on a GTC 4?
I think it was a yellowy galvanised/zinc finish originally, but it is mouldy/rusty/ grubby & won't clean .
I can paint it & if I do, what colour?
Thanks
Regards
Ian Levy
Re: GTC 4 Brake Servo
Posted by simon
Here is a link to the 'old' that I took off of my 400 (as you can see it is almost new and it's a long story). It shows the finish that is on a new one today and I don't think it has changed over the years. I think it is known as 'gold nickel plating' a sit is very similar to my track-rod ends. I did see some spray paint at a how that was claiming to reproduce this finish and a classic car magazine in teh UK said that it did a pretty good job
Here is a link to the 'old' that I took off of my 400 (as you can see it is almost new and it's a long story). It shows the finish that is on a new one today and I don't think it has changed over the years. I think it is known as 'gold nickel plating' a sit is very similar to my track-rod ends. I did see some spray paint at a how that was claiming to reproduce this finish and a classic car magazine in teh UK said that it did a pretty good job
Re: GTC 4 Brake Servo
Posted by Tom
Hi Ian,
I believe the finish is called Gold Cadmium Plating. A company called Eastwood in Pensylvania sells a kit that mimics this finish with three spray cans, but I'm not sure how good it looks.
http://www.eastwoodco.com
Put this part number in the "search" box, and you can see what it is:
10331Z
My advice is paint doesn't stick to rust and dirt very well, so taking all the rust off may be the only option. From Simon's picture, it looks like the canister is crimped together, so it will be quite a job to disassemble it, sand blast it, and plate it, but it will end up looking as nice as Simon's! Just make sure you can get the rebuild parts before you take it apart in case you damage any of the seals.
Another idea is to try sanding the rust off with sandpaper and using the spray cad plating. Tape all the openings up, so none of the debris gets inside. Good luck, and let us know how it goes!
Tom
Hi Ian,
I believe the finish is called Gold Cadmium Plating. A company called Eastwood in Pensylvania sells a kit that mimics this finish with three spray cans, but I'm not sure how good it looks.
http://www.eastwoodco.com
Put this part number in the "search" box, and you can see what it is:
10331Z
My advice is paint doesn't stick to rust and dirt very well, so taking all the rust off may be the only option. From Simon's picture, it looks like the canister is crimped together, so it will be quite a job to disassemble it, sand blast it, and plate it, but it will end up looking as nice as Simon's! Just make sure you can get the rebuild parts before you take it apart in case you damage any of the seals.
Another idea is to try sanding the rust off with sandpaper and using the spray cad plating. Tape all the openings up, so none of the debris gets inside. Good luck, and let us know how it goes!
Tom
Re: GTC 4 Brake Servo
Posted by Lee 2811
The original finish is gold iridite over either cadmium or zinc. I deal with a plater here in Virginia who does lots of industrial stuff, and does some excellent work using zinc,which looks exactly like the Cad. Cad plating is getting hard to find, Cadmium is toxic and literally costs more per ounce than gold. If your servo can be completely disassembled, it can be replated.
The paint is sold by Eastwood. I have seen some items done with it, the effect is quite good. It does not have the transparent look of the original plating, but will certainly fool the casual observer.
Good Luck.  
The original finish is gold iridite over either cadmium or zinc. I deal with a plater here in Virginia who does lots of industrial stuff, and does some excellent work using zinc,which looks exactly like the Cad. Cad plating is getting hard to find, Cadmium is toxic and literally costs more per ounce than gold. If your servo can be completely disassembled, it can be replated.
The paint is sold by Eastwood. I have seen some items done with it, the effect is quite good. It does not have the transparent look of the original plating, but will certainly fool the casual observer.
Good Luck.  
Re: GTC 4 Brake Servo
Posted by Deane
Your booster is not crimped together! The two halves rotate a bit to come apart, as far as I know.
Your booster is not crimped together! The two halves rotate a bit to come apart, as far as I know.
Re: GTC 4 Brake Servo
Posted by Pete
It is no big deal to get parts re-plated as per original. The engineering company I used to work for used to get the mild steel components 'Gold passivated' plated or zinc plated all the time. I used to use the same place and it is cheap!.
This is way better than painting and why manufactures use it, plus it actually saves them money.
But you do have to strip the components down to the individual parts as they acid dip them first to clean them. As for rust I think a wire brush effort to remove scaling would be all that is required, not necessarily sand blasting, as the acid dip process I believe helps here to (? not sure about this, would have to check with plater).
The only worry I had, and it is the same when you get anything chrome plated, etc., is if the place would loose the part as these places are usually pretty messy.
Painting won't last as well, and if you are going to strip it down to paint, then you might as well get it plated.
Good luck
Pete
It is no big deal to get parts re-plated as per original. The engineering company I used to work for used to get the mild steel components 'Gold passivated' plated or zinc plated all the time. I used to use the same place and it is cheap!.
This is way better than painting and why manufactures use it, plus it actually saves them money.
But you do have to strip the components down to the individual parts as they acid dip them first to clean them. As for rust I think a wire brush effort to remove scaling would be all that is required, not necessarily sand blasting, as the acid dip process I believe helps here to (? not sure about this, would have to check with plater).
The only worry I had, and it is the same when you get anything chrome plated, etc., is if the place would loose the part as these places are usually pretty messy.
Painting won't last as well, and if you are going to strip it down to paint, then you might as well get it plated.
Good luck
Pete
Re: GTC 4 Brake Servo
Posted by Simon
The servo should split by rotating teh two halves as you say Deane. I haven't tried it with mine but it is easy to see how when it is viewed end on.
The servo should split by rotating teh two halves as you say Deane. I haven't tried it with mine but it is easy to see how when it is viewed end on.
Re: GTC 4 Brake Servo
Posted by Deane
Looks like you might have a similar booster to mine (330GTS), a Bonaldi? A shop in San Jose, California rebuilt mine - it had a "folded bladder" (sounds uncomfortable!) which resulted in an overboosted feel.
Looks like you might have a similar booster to mine (330GTS), a Bonaldi? A shop in San Jose, California rebuilt mine - it had a "folded bladder" (sounds uncomfortable!) which resulted in an overboosted feel.
Re: GTC 4 Brake Servo
Posted by Dr. Ian Levy
Thanks Deane but San Jose is just a little out of the way. I could not twist & split the two halves to get them plated as Pete suggested. I took them to my local brake specialist who sent me to J & L Spares, just a few minutes from my home.
I walked in with my servo & the owner(Mike) says from across the room
" Bonaldi, Ferrari or Maserati?" I give him the servo & he says " Ferrari - Maserati have a longer pushrod"
This company does it all & has been doing it for years on my own doorstep. Check out www.jlspares.com.
He intends to split it, overhaul the workings & replate the casing as original
To split the casing is no simple task because of a large bakelite section inside the top half
I will let you know how it goes.
Regards & thanks
Ian
Thanks Deane but San Jose is just a little out of the way. I could not twist & split the two halves to get them plated as Pete suggested. I took them to my local brake specialist who sent me to J & L Spares, just a few minutes from my home.
I walked in with my servo & the owner(Mike) says from across the room
" Bonaldi, Ferrari or Maserati?" I give him the servo & he says " Ferrari - Maserati have a longer pushrod"
This company does it all & has been doing it for years on my own doorstep. Check out www.jlspares.com.
He intends to split it, overhaul the workings & replate the casing as original
To split the casing is no simple task because of a large bakelite section inside the top half
I will let you know how it goes.
Regards & thanks
Ian
Re: GTC 4 Brake Servo
Posted by Tom
Thanks Ian!
This looks like a source for not only brake boosters, but also Lucas wiper motors! Let them know I'll be putting them on my "suppliers" page.
Tom
Thanks Ian!
This looks like a source for not only brake boosters, but also Lucas wiper motors! Let them know I'll be putting them on my "suppliers" page.
Tom
Re: GTC 4 Brake Servo
Posted by Deane
It looks like you've found exactly the right place! And no trip to California required!
It looks like you've found exactly the right place! And no trip to California required!