Broken Brakes

[Apis Mellifera]

My SIII 88 requires quite a bit of leg power to bring things to a stop. It has a duel line MC with servo. I'm fairly certain that the servo isn't working, although I've never driven a power-braked Series for comparison. The system could use a bleed, as I've got two-pump brakes, but it still stops on the first pump, just with a little more travel than I'd like.

My question is, seeing as how a major brake service is in the cards and seeing as how I'm cheap, I'm exploring second hand options.

So:
What is the make/model of the standard SIII servo?
Was this servo used on any other vehicles?
What is the make/model of the duel line 88 MC
Found on other vehicles?
What'll happen if I use a 109 MC?
I can rebuild the MC, but I need a new reservoir. Available separately somewhere?

Anyone have a good/rebuildable MC and/or Servo for sale?

Many Thanks,
Matt

[thixon]

Matt,

That stinks. You did'nt mention a leak anywhere though. Is the system leaking fluid, or has it just been THAT long since you paid attention to the brakes?

You can't use the 109 cylinder. To accomodate the actuation of the dual wheel cylinder system on the 109, it has a greater volume, and longer stroke (I think) than the 88 cylinder.

You used to be able to buy the reservoir seperately. However, I tried to find one about 8 months ago, and could'nt. I ended up just buying a whole new cylinder.

TA's website has some info on part numbers for the various boosters used in the US, but its series rover specific. I'm not aware of other vehicles that used the same cylinder or booster, so someone else can weigh in there. All I can add is that after having owned/worked on a bunch of different brit cars, I can't recall one that had the exact same setup. either the foot of the cylinder was oriented wrong, volume was different, etc.

good luck.

[Jim-ME]

I am using a 109 MC with a servo on my 88 and have had no problems. IIRC TeriAnn told me to reverse the front and rear lines coming out of the MC as compared to my dual line 88 MC because 109s are different than 88s.
Jim

[thixon]

I am using a 109 MC with a servo on my 88 and have had no problems. IIRC TeriAnn told me to reverse the front and rear lines coming out of the MC as compared to my dual line 88 MC because 109s are different than 88s.
Jim

Well, my assumption was that whatever circuit you connected to the larger volume cylinder would actuate too quickly. Guess that's what I get for making and ASSumption! Thanks for the info Jim.

[NickDawson]

Im using the 109 MC on my 88 as well, but I have 109 brakes on the front end.

My server is also out, and I have to say, it doesnt make a tremendous difference in performance - I have one pump that stops pretty well (although I don't ever tailgate ).

A servo rebuild is on my list for 2010 - will be curious to follow your results Matt and what you find out. I decided to rebuild since I'm not missing it anyway and if I totally botch it I won't be at a loss.

[Apis Mellifera]

I've never serviced the brakes. For all I know they could be original, but they work very well aside from the pedal effort and travel. On the first pump, I can lock the wheels, but the pedal travels less if I pump them twice. The effort, while not extreme, is greater than my non- power assist cars. According to what I've read, it appears I have the Girling servo. I see no numbers on it. The MC may have leaked in the past and was possibly rebuilt by the PO. The fluid is blackish so I'm preparing for a major rebuild.


I disconnected the vacuum line and pulled a vacuum on the servo. It seemed to hold a vacuum, so I don't know if it's working or not. I've driven British cars all my life, but the pedal effort in my LR is by far the greatest.

[Tim Smith]

I drove my lightweight for ages with the vacuum boost disconnected and even though it was a bit harder peddle, it wasn't too difficult to stop.

Try disconnecting the vacuum boost line and plugging the line on the intake side and see if there is much difference. That should tell you if it's working or not.