Alfa Romeo Forums banner
1 - 9 of 9 Posts

·
Registered
Joined
·
71 Posts
Discussion Starter · #1 ·
So…my recently installed OKP Sport Exhaust on my USA 1976 2.0 Alfetta GT sounds and performs wonderfully. No issues the past year or so including during some warm weather (not hot) driving. BUT I recently had some brake issues = squishy pedal falling to the floor after some hard driving. After cooling and a couple of pumps the brake feel would return to normal. Master cylinder is a relatively new 4 years ish so initially thought not to be an issue.

First things first, fully bled the brakes and new fluid all around. Pedal felt solid and stayed for a few days before I put the car down for testing. After some hard testing over a few miles all felt well…then pedal went back to the floor. A couple pumps and feel mostly returned. Limped home super slowly. Entering driveway there is smoke emitting under the hood and upon opening I see what appears to be the master cylinder dripping onto the new stainless steel manifold AND catching on fire! Fire extinguisher to the rescue.

Obviously master brake cylinder is leaking = replace it. Remember that this was a relatively new part - 4 years.

BUT thinking that the TRUE cause of this might be the heat now generated by the stainless steel manifold? Basically cooking the brake fluid and master cylinder?

Ideas and solutIons?

1) Folks say heat wraps can cause the headers to crack. Also apparently I need to take the manifold off to do the wrapping properly - not a task I am looking forward to.
2) Heat shielding. Picture of an idea attached. Not sure I can manufacture as lovely looking piece.
3) Upgrade to a higher temp brake fluid - I found a Super Dot 3 that goes to 500F (260C) as my previous regular Dot 3 went to 400F.

Leaning towards a combination of #2 and #3.

Car Vehicle Motor vehicle Hood Automotive design
 

·
Registered
Joined
·
650 Posts
So…my recently installed OKP Sport Exhaust on my USA 1976 2.0 Alfetta GT sounds and performs wonderfully. No issues the past year or so including during some warm weather (not hot) driving. BUT I recently had some brake issues = squishy pedal falling to the floor after some hard driving. After cooling and a couple of pumps the brake feel would return to normal. Master cylinder is a relatively new 4 years ish so initially thought not to be an issue.

First things first, fully bled the brakes and new fluid all around. Pedal felt solid and stayed for a few days before I put the car down for testing. After some hard testing over a few miles all felt well…then pedal went back to the floor. A couple pumps and feel mostly returned. Limped home super slowly. Entering driveway there is smoke emitting under the hood and upon opening I see what appears to be the master cylinder dripping onto the new stainless steel manifold AND catching on fire! Fire extinguisher to the rescue.

Obviously master brake cylinder is leaking = replace it. Remember that this was a relatively new part - 4 years.

BUT thinking that the TRUE cause of this might be the heat now generated by the stainless steel manifold? Basically cooking the brake fluid and master cylinder?

Ideas and solutIons?

1) Folks say heat wraps can cause the headers to crack. Also apparently I need to take the manifold off to do the wrapping properly - not a task I am looking forward to.
2) Heat shielding. Picture of an idea attached. Not sure I can manufacture as lovely looking piece.
3) Upgrade to a higher temp brake fluid - I found a Super Dot 3 that goes to 500F (260C) as my previous regular Dot 3 went to 400F.

Leaning towards a combination of #2 and #3.

View attachment 1734809
I doubt the exhaust is the cause, sounds like a fitting is probably loose. It shouldn't just drip and the heat would make it boil not leak. Besides don't stick with dot 3, just bump up to 4 you can mix it with 3 and everything. Double check your fittings make sure they're tight and have the right flare on them (should be bubble not double) and mix in some dot 4 or flush your 3 and swap to 4.
 

·
Registered
'78 Alfetta GTV, '59 Fiat 1200 Cabriolet, '97 Jaguar XJ6 Van Der Plas
Joined
·
1,982 Posts
I had a similar problem when I lived in South Florida. Between the Florida heat and the cast iron manifold I felt the clutch and brakes were getting squishy. I now have a new, to me, Alfetta GTV that will be getting a similar cast iron setup with the rest ANSA freeflow from the 70's. I have been checking out similar solutions from Summit Racing.
 

·
Registered
Joined
·
71 Posts
Discussion Starter · #4 ·
I had a similar problem when I lived in South Florida. Between the Florida heat and the cast iron manifold I felt the clutch and brakes were getting squishy. I now have a new, to me, Alfetta GTV that will be getting a similar cast iron setup with the rest ANSA freeflow from the 70's. I have been checking out similar solutions from Summit Racing.
I like this. Not sure the install will look as clean as using an exhaust wrap, but maybe easier to install without removing the headers. The picture shown here is very nice and clean looking. Given the insulating side I doubt there will be any of the inevitable rattling that is likely to occur with a heat shield.
 

·
Registered
Joined
·
5 Posts
My Alfetta saloon/sedan used to fry its brake master cylinder on a regular basis - so (on the advice of an ex-Alfa race team engineer who I used to know), I made this heat shield that hangs on one of the master cylinder nuts. That was 15 + years ago, and it's been faultless ever since...

Motor vehicle Hood Automotive design Automotive exterior Gas
 

·
Registered
Joined
·
71 Posts
Discussion Starter · #6 ·
My Alfetta saloon/sedan used to fry its brake master cylinder on a regular basis - so (on the advice of an ex-Alfa race team engineer who I used to know), I made this heat shield that hangs on one of the master cylinder nuts. That was 15 + years ago, and it's been faultless ever since...

View attachment 1735296
Also a very neat solution! Thanks. I may try this as it seems less intrusive than the others and maintains visibility. Funny enough, I also talked to a racer yesterday (Non-Alfa) who said this is a very common problem and had seen the fluid catch fire on many cars. He suggested a spray on heat reflective paint that acts much like ceramic coating and on the more radical side to lift the hood or cut out the fenders!
 

·
Registered
'59 Giulietta Sprint 101, '79 Alfetta GT
Joined
·
144 Posts
My Alfetta GT has a heat shield between the exhaust and brake MC, I always assumed it was factory but maybe not? My car was modified mildly in the ‘80s so maybe it was added. I’ll snap a photo Monday.
- Matt
 

·
Registered
Joined
·
71 Posts
Discussion Starter · #8 ·
My Alfetta GT has a heat shield between the exhaust and brake MC, I always assumed it was factory but maybe not? My car was modified mildly in the ‘80s so maybe it was added. I’ll snap a photo Monday.
- Matt
Somewhere on deep into this BB and years ago, not Alfetta I think, it was mentioned that there was a factory heat shield installed in some models for this task. I only came to this conclusion after seeing an older classic Jaguar using an exhaust wrap on his stainless headers for this exact reason…after a few Alfa guys telling me this scenario was unlikley which seems pretty naive. Or they just don’t drive their cars Italian “tune-up” style ;-)
 

·
Registered
Joined
·
71 Posts
Discussion Starter · #9 ·
Ps. Forgot to mention that I believe my car had been dropped an inch or two when a previous owner installed Koni’s - the racer mentioned this as a problem with his cars as when he drops them it prevents the heat from escaping - not that dropping the Alfetta GT is as dramatic, but could be an aggravating factor combined with the new stainless exhaust system and high revving nature of the system.
 
1 - 9 of 9 Posts
Top