Brake Bleeding a Spider

**Gubi** · #1 (**permalink**) 10-19-2003, 10:47 PM

So I want to flush and replace the brake fluid in my '91 Spider. Pedal feels fine so there's no air in the lines, I just don't know how old the stuff in there is so I figure better safe than sorry.

Here's my question...the service manual says to do both right brakes at the same time, and then both left brakes. Strikes me as a bit odd, as the way I've always seen it done is to start with the rear right, then the rear left, then front right, then front left...working from the farthest to the nearest. I don't see anything in the tubing layout that suggests to me that this wouldn't work, and since there's only one of me (well, and the wife to pump the pedal) it would definitely be a lot simpler to do it one at a time. Any comments would be appreciated.

Also, one more newbie question - how much new fluid do I need to flush through each line?

**Sniady** · #2 (**permalink**) 10-19-2003, 11:58 PM

Well it's not a single reservoir. Dual. So one line goes to the back, and one to the front.

They say right front and rear first. I agree with the front, but the rears furthest brake line is on the left side. Stumped.

djone101 · #3 (**permalink**) 10-20-2003, 08:26 AM

Bleeding the dual master cylinder system is PITA. Don't expect to do it only once. I would recommend using an Eezi-bleed type system that pressurizes the circuit so all you have to do is go round and loosen the bleed nipples. You only need about 10 PSI max for thsi to work, don't just connect up to a fully inflated tyre as you are pressurising seals on the low pressure side of the system that don't noramlly seeanypressure.

You will need to have front and rear open together on one side, then do front and rear together on the other side. There is also a bleed nipple on the m/c itself which takes out any air trapped between the cylinder and the reservoir. I do that one first. You should be able to refill the whole system with about 1 to 2 litres of fluid but have plenty on hand, you can get through a lot due to having front and rear open together - depends how fast you can move around the floor.....

Good luck.

DaveC · #4 (**permalink**) 10-20-2003, 09:40 AM

I had to change the mc on my spider last year. I flushed the system the old fashioned way, furthest to nearest. No problem with brake performance. Buy two quarts of dot4 and you should be all set.
Dave

memphis raines · #5 (**permalink**) 10-20-2003, 09:51 AM

actually my feeling is youre supposed to always do it from the wheel closest the MC till gradually further away.

**papajam** · #6 (**permalink**) 10-20-2003, 04:49 PM

Quote:

Originally posted by Gubi

Here's my question...the service manual says to do both right brakes at the same time, and then both left brakes. Strikes me as a bit odd, as the way I've always seen it done is to start with the rear right, then the rear left, then front right, then front left...working from the farthest to the nearest.

**papajam** · #7 (**permalink**) 10-20-2003, 04:59 PM

Just read Dave's procedure which is for RHD floor mounted pedal cars with the series 2 master cylinder. Neither the series 1 RHD M/Cs nor the US version floor mounted tandem M/Cs have bleed screws. Which is WHY they're so bloody hard to bleed!

**Favali** · #8 (**permalink**) 10-20-2003, 05:25 PM

USA Series 4 Spiders (91-94) have 3 brake lines. Each front wheel is served by a dedicated line from the front of the dual MC to the caliper. The rears are on a single line from the rear of the dual MC that splits at the differential. As I see it, you can bleed each front on its own and the rear likewise.

Based on this dual MC-3 line layout, I have replaced the fluid and bled the system with little regard for order. Seemed to have worked fine. Or did it??

Also if you use a colored fluid you will know when the fluid change is completed.

Thoughts?

Farace · #9 (**permalink**) 11-27-2004, 02:43 PM

Resurrecting this thread for a quick question and an observation.

1) Bought an Eezibleed. Pressurized spare tire to about 15 pounds and connected it. Fluid from front brakes flowed, but slowly. Rear brakes barely dribbled. Yes, I kept checking the air pressure in the spare tire and kept it over 10 pounds. I've never used a pressure bleeder before; I expected more flow. I'm used to "pump the pedal, spurt!" bleeding. Should I have been getting more flow from this?

2) Regarding the question of why Alfa specified bleeding a front and a rear brake at the same time, I bumped into this this morning when I was reading my manual. The '71 manual tells me to bleed one front and one rear at the same time, but without specifying which side, just a front and a rear. Then it goes on to explain that with the tandem system, you can't fully depress the pedal with only one bleeder open because the other side of the system will pressurize and oppose your effort. I decided that's the only reason they said to open a front and rear simultaneously, so you can press the pedal all the way down. Since I was pressure bleeding, I figured I didn't need to do front and rear simultaneously, since I wasn't going to be worrying about the pedal travel like for pump bleeding.

As for whether to bleed furthest to closest or closest to furthest, I've heard arguments for both ways. I can never remember what I decided last time I bled brakes. This time I went closest to furthest. It probably doesn't make much difference on this system, since the fronts won't affect the rears and vice versa.

77SpideRacer · #10 (**permalink**) 11-27-2004, 04:42 PM

Quote:

Originally Posted by Sniady

but the rears furthest brake line is on the left side. Stumped.