Brake Booster Help C4

[69VETTE]

Hello Guy,

This morning i decided to take the beast out for a run & put some fuel in here, when I noticed that the break pedal felt awfully hard like I had no vacuum. I then took the car to my brothers to look at the car, and there we found out, that the plastic brake booster had cracked from the diaphragm side, right thru to the back.  I gather its the original one that came with the car.. See Pics...







Does anyone know whether you can use a GM Holden booster as a replacement, or do i need to buy a replacement from the states?.. I wanted to ask, has any one used a similar commodore booster, as they look the same

[69VETTE]

Looking at the Corvette Central webb, it looks like this must be the one....

http://www.parts123.com/parts123/yb.dll?parta~dyndetail~Z5Z5Z50000050f~Z5Z5Z510178~P399.00~~~~S42J19KL1212418724950h~Z5Z5Z5~Z5Z5Z50000050F~~~

[Vettech]

At $400 I would imagine that black paint is covering up the Gold it's made out of.

[69VETTE]

At $400 I would imagine that black paint is covering up the Gold it's made out of.

And that's US dollars, plus you have to add shipping... oucch......

[Vettech]

I have don't keep abreast of recent cars, but I do go to one of those wreckers were you get the bits off yourself, a walk around the different models allows me to see what I can modify or update onto my shopping trolley. But I'm sure we must have members familiar with interchangeable parts.

[gtc]

Sirfixalot should know the answer to this.

[69VETTE]

Thanks Guys, ive actually found two sellers on ebay selling genuine GM parts that are about $335 -$370 with shipping. Just need to pull out mine to check backing mounts to be sure. I think its best to stick to AC Delco products.

However, in still going to see if anyone has them here. I also have found reproduction ones for about $160 shipped.

If someone still has use some holden part, let me know.

[gtc]

However, in still going to see if anyone has them here.

Scott at C.A.C. (ad at bottom of forum pages) may have a Delco one in stock.

Some options here:

https://pontiworld.com.au/usgmsp/index.php?cPath=24_212&osCsid=82e49267ef0841625a36aa049f2c8653

Re Holden compatibility, call "Sirfixalot". His number is in the magazine and in the Club's contacts list.

[sabre]

I'd be taking a close look at clearances before fitting a new unit. Those 'pretty' heat shields look horribly close to the booster body and it would only take a soft or broken engine mount to have the new booster go the same way Just a thought but that kind of break is not common

[69VETTE]

Hello Sabre, Yeah I see what you mean, never crossed my mind actually.  Personally I thought, the booster being 18 years old and close to the engine, its gotten hard over time, and with the vacuum being inside, just punctured.. tho you can never be too sure!

I don't think its the engine mounts, I think that they may have been changed at the time the motor was rebuilt,  tho I will ask the owner. From my discussion with him yesterday, apparently its the original booster that was on the car when converted in 1993.

So that like, its an 18 years old booster.

I appreciate your feedback regardless and will look at it again.. and see if the reason was the engine...  my brother is a mechanic, so we will jack it up and see if it touches.

[69VETTE]

And thank you Gtc..

Will give Ponti World and Scott & CAC a Call first to see... But I have to take out the original first to make sure its the same one.

[Jethro]

Hey Michael,  if you planning to see Dave at Ponti World give me a heads up and we'll catch up don't forget I live in the Gong 

Jethro

[sirfixalot]

I think when converted to RHD they either change the booster or master cylinder to get clearance on engine / mudguard so if you buy one ex US it may be unusable. Easiest way would be to take it off & take to a brake shop to get a comparable replacement

[Camo]

I'll stand corrected on this but I believe there is an aftermarket metal version of these.  I may be wrong but worth checking out.

[69VETTE]

I'll stand corrected on this but I believe there is an aftermarket metal version of these.  I may be wrong but worth checking out.

Your correct Cam,  Just got off the phone with Scott from CAC and highly recommends going with the metal one, because its very close to the engine.

[Camo]

Scott's the man.  A wealth of knowledge

[Ausrs]

My 1987 had a split plastic booster,I used the booster off of an 84 as they were metal
I have been told since that an EL Falcon uses the same booster as the C4with the vacuum hose out of the other size as its an Aussie car

[69VETTE]

YEP...I  just got off Corvette Central web site and purchased myself a metal brake booster (already painted black) to replace the one that's cracked. Its designed to suit 1986-1991 Corvettes !... its a waiting game now !..

I will upload pics during the process, when were doing the replacement for others if they have the same problem as a guide.

[Ausrs]

Be careful with the replacement and how far it pushes the brake master cylinder,I replaced the booster and had to replace tha master about 4 weeks later, and if it is anything like the C4 remove the seat before you lay down to undo the bolts

[69VETTE]

Be careful with the replacement and how far it pushes the brake master cylinder,I replaced the booster and had to replace tha master about 4 weeks later, and if it is anything like the C4 remove the seat before you lay down to undo the bolts

Thank you Ausrs for that advice.. Scott also from CAC also advised me to remove the seat, its alot easier that way.   Im hoping the booster wont affect the master cylinder, as its running an upgraded system and C5 Z06 brakes...

Now you have me worried... damnn... it should be good....

This is the product that i bought on line...

http://www.parts123.com/parts123/yb.dll?parta~dyndetail~Z5Z5Z50000050f~Z5Z5Z518164~P139.95~~~~S42L08E4FN12121305550C~Z5Z5Z5~Z5Z5Z50000050F~~~