Is the cast iron weight on bottom of ABS accumulator on Gen 2 really necessary??

The ballast really complicates the removal of the accumulator. Now that the accumulator is out the question arises as to the purpose of this ballast and whether to try install without it as an experiment. If noise reduction is the purpose of the weight just how bad will the noise be? It is hard to imagine that the vibration from the pump is really enough to generate a noise so obnoxious that it would be intolerable. In fact, after hearing that thing buzz every 10 seconds it might be a joy to hear it only every now and then. Furthermore, if leaving it off makes the installation of the new accumulator easier with less risk of damaging brake lines then maybe the risks outweigh the benefit on the old car? Not only that but why haul around extra pounds of useless metal? Is the ballast simply overengineering and actually just theoretical? I am tempted to leave it off and find out.

Interestingly all the youtube videos showed pulling the actuator and frame out with ballast still hanging on bottom, but I got stuck and was able to take out the two bolts and remove the ballast or weight and then easily pull the rest using the two step method. Still, if no needed for more than a minor noise issue I may not put it back in. I have a couple of robot mowers that had iron ballasts in them, and I took the ballast out permanently 2 years ago and it lightened the droids and gave them extra range. So this finding makes me wonder if this is similar case with the ABS weight. Any thoughts or opinions appreciated.

 

For what it is worth I just powered the car up after putting it all back together. Haven't bled the brakes yet, but certainly the new pump is no louder than before. Sounds different, but then full of air too. Will give details later. It definitely was easier to put ABS module back in without the ballast. I found it so much easier on the 70 year old body to use a pulley hoist to help with the heavy lifting. Naturally I did remove the wipers etc, but I also took the hood off to give more light and clearance for he hoist.

If it weren't for one single 10 mm nut on the back side of the module that secures one of the bushing mounts one could avoid dragging the big bracket out just to remove the ABS. I wondered if indeed it could be reached with small hands. Just loosening it would be enough to lift it and pull it out, and probably the weight would come with it in that case with no hassles. Since I put the ABS in with no weight for this test I didn't bother testing that idea. More later.

 

For what it is worth, the ABS blob is back in car WITHOUT the ballast. No unusual vibration detected. Possibly there were concerns about long term vibrating the brake lines too much and metal fatigue etc. Books and movies have been made on that subject. BUT the car is 15 years old, and I am 70 and only drive 100 miles per month. Somehow I think the ballast won't be missed on this car, and it sure made reinstall easier on the old man. So its done. WOW. what an improvement to get rid of that constant buzzing every 10 seconds. Been my list for 3 years and done. I counted down to 3 minutes from first buzz...nada! Haha...love it. And thanks a million to McGeorge Toyota online parts. Got the part for $1250 incl. tax and shipping. Best quote for an installed one I had was $2000 and a 1500 mile road trip. I ENJOYED the project!!!

The Techstream I got on Amazon wouldn't show the "Utility" button to bleed the brakes and actuator, but there was an "Active Test" button so I ran that about 12 times, twice to prime and then twice on each wheel starting at rear and ended up with 2 quarts being used and solid brakes so I assume it did the trick. Had one tiny ooze on one of he fittings going into the ABS but there was room to torque it plenty more and stopped the leak. Success!! The ballast in my iron recyle pile! Haha

Now that the wipers off I am meditating over installing hardware cloth over all those openings in channel that lead to air intake and using spray foam to seal up down on each end where there are some mouse size holes. Most mice nests I discover right away and are in the engine comparment, but he is going inside to get some kind of white insulation which must be inside the car because I can't find any on the outside. It's a constant battle, but don't want my wires getting chewed up after all this work on the ABS, new LFP batteries, rotors and disks etc.