Strange Brake Bleeding Problem

[DrinkMan]

We changed the brake light switch on our S2. While only a little fluid dripped out, I thought we should bleed the brakes since we opened up the system. I also noticed that the brake pedal was about 1/2 way down before the brake lights came on.

Because only a very small amount of fluid came out, I made the mistake of just going to the right front brake that was near the brake light switch. It bled nicely, a few pumps, some bubbles, then no bubbles. ah...nice. why not just check out the left front brake while I'm under here? So, went to left front brake. First pump, a little air, 2nd pump, a little air. 3rd pump, massive air, then nothing but air with every pump afterwards. Fluid level in still good in reservoir. WTH?

Ok, lets blame ourselves for being lazy and not starting at right rear (furthest from master cylinder). Decided to start over and bleed from there. Nothing but air. Tried using vacuum instead. Nothing but air. No lowering in reservoir. Pump method again. air.

(note - system worked fine prior to all our messing with it. our fault for touching it)

Any ideas? Later, we may try just bleeding the master.

[Panda]

I wonder if the piston is stuck down the master cylinder, thereby blocking off the compensation port. Try operating the pedal by hand, you should feel some slight resistance if the piston is moving. If not, a master cylinder overhaul is required.
Alan P.

[vxah]

Are you closing the nipple between pumps? Sometimes air will get sucked back in past the threads of the nipple?
I would get one of those "easy bleed" kits that pressurise from a tyre, much less likely to damage seals etc and no air going back in?

[Certified Lotus]

Welcome to working on a Lotus Dan You fix one thing and something else appears that needs attention.

With the brake system sealed, do you still have a hard pedal? Or is it soft and goes to the floor? As previously mentioned, might be time for a master cylinder rebuild. Full fluid reservoir suggests a seal issue. Or wrong size push rod for the master cylinder.

[DrinkMan]

Glen,

You are so right. There is never a single root cause of problems on the Elan (our record in troubleshooting on this car is 4 problems for a single issue).

Decided to start over because we worked too late last night on this. Used a vacuum pump. There was just too much air in the system. Emptied the system. Fresh fluid. Did it by the book. All is well with the world. Hard brake. Brake light comes on a little earlier (still not as fast as a switch on the pedal). Thanks y'all for the advice (you scared me with the master cylinder overhaul - we would not be able to drive the car today if we did that!).

Dan

[Certified Lotus]

Dan, you have the right attitude, start from the beginning, pay attention, do it right and the end result is what you hoped for. Most of the time, if your lucky and are good at wishing.

Ahhhhhh, life with an Elan. Thank goodness they are so much fine to drive.

[DrinkMan]

Life with an Elan is similar to life with an Alfa Romeo. Similar issues and similar joy.

After getting brakes all fixed, we took it for drives. Great joy (although, in tradition of Lucas electrics, every time I turned the wheel, the horn honked.... luckily, since we were the ones that just redid the horn system, easily fixed). Now, as soon as a working gas gauge comes back from Nisonger, we will have a fully functional car (at least temporarily....after all, it is an Elan).