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siii8873
06-11-2011, 07:14 PM
I adjusted my brakes on my 109. They are a single system without vacuum assist. They went from poor to fair. Still require a pump to get much brake at all. Is this normal, my other rovers are 88's with dual systems and they stop fine.
How much improvement would there be if I upgraded to a vacuum assist double system?

Partsman
06-11-2011, 07:40 PM
From what I've been told while researching my 109, it's a matter of adjustment, I've done the same as you, with the same results, but I think I have to do some more adjusting. I've been told that the breaks should catch about 1/3 to 1/2 of the way down with-out pumping the pedal.

Linus Tremaine
06-11-2011, 09:00 PM
I find that the only way to really get good brakes in a 109 (or any other vehicle) is to make sure you bleed them completely. This is hard in a 109 because of the dual front wheel cylinders. Best way to do it (there are several) is to get a pressure bleeder. Also, make sure your brake pedal is adjusted per the manual. I think 6-1/4" from the floor of your truck with about 1/4" of play otherwise the plunger wont be in the best position inside the cylinder. If you dont have good brakes, something is wrong. There is no reason a 109 should have lousy brakes if everything is in order.

Putting in a dual circuit system will only partially help solve this problem. You will have less trouble getting the trapped air out of the master, but the same trouble getting it out of the front top wheel cylinders. Still, you would need a pressure bleeder. A dual circuit system is a useful upgrade, but give your brakes the chance to prove themselves by getting them to work properly before you try to upgrade them.

jac04
06-12-2011, 07:44 AM
Still require a pump to get much brake at all. Is this normal...
No. When properly adjusted and all air out of the system, the 109" brakes are very strong (well, at least when stopping a forward-moving vehicle - reverse is another story due to the twin leading shoe design).

Your problem sounds like air in the system. It can be a real PITA to get the air out due to the lack of a bleeder on the top cylinder. My Lightweight is post-1980, so it is fitted with the 109" brakes front & rear. I found that just using a pressure bleeder didn't move enough fluid fast enough to get all the air out. I used a combination of a pressure bleeder and the pedal-pumping method. The pressure bleeder would keep fluid in the system while pumping the pedal rapidly moved lots of fluid very quickly to get all the air out. My brakes are rock hard.

Partsman
06-12-2011, 05:20 PM
Is it possible to replace the top wheel cylinder without a bleeder, with one that does?

bobzinak
06-12-2011, 07:04 PM
You must slacken off the brake adjusters to minimize the air inside the wheel cyl. to bleed them properly. that is loosen them to the max. bobzinak..

jac04
06-12-2011, 07:59 PM
^^Yes, remember to do this!

LaneRover
06-13-2011, 05:40 AM
Is it possible to replace the top wheel cylinder without a bleeder, with one that does?

I believe that some people have done this. Not sure what is done but if my recollection of reading fleeting posts on this forum is correct I do remember someone posting this very 'fix'.

jac04
06-13-2011, 10:44 AM
Here is some good info:
http://www.roversnorth.com/forums/showthread.php?t=6635&highlight=bleeding