Hey Attitude

The vacuum pump/pressure tester can be bought at SEARS or Autozone.
It's a hand type pump with a vacuum/pressure gauge on it with a small
reservoir to catch the fliud. This makes it a one person operation .
The self pumping technique should work so as long as the volume in
the tube is greater than the cylinder volume, however, crack the bleeder
screw and leaving it open while the pedal is in the upstroke leads me
to think air is being drawn back into the caliper , and the last stoke in
bleeding the lines is an upstorke , leaving air trapped ? Agree ?
Vacuum "pumps" can also be bought and used with a aircompressor tank.
The air pressure is used to drive a vacuum pump that is fitted to the lines.
The hand method is time consuming , it took about an hour and half to do all 4 lines.

 

I didn't notice a difference when I put the Valvoline synthetic in. The reason I went to a synthetic was that I thought it had a higher resistance to moisture absorbtion. After a month of driving, the fluid changed color like any other DOT types do.

I haven't found a budget bleeder I liked and for me, spending $$ for a 30K mile interval service tool was not practical. Usually I have the Mrs. pump the brake pedal. Bleeding was easy enough that I was able to access the screws and I didn't even have to use a jack. (I'm a string bean of a guy so crawling under the car isn't difficult.)

 

I am going to bleed them tomorrow and will report back on what my "Feelings" are.

I was thinking about the bleeder vacuum and I'm trying to vision it working correctly as I envision the master cylinder piston pump pushing the fluid into the lines when depressed. When it is released it re-primes the pump with fluid from the reservoir.

So I am thinking the vacuum bleeder may not be able to completely remove and replenish the fluid in the lines for that reason. Maybe I am wrong.

The squeeze bulb I bought today has a one way valve on it. I'm hoping I can hook it up to the bleeder valve and push and release the brake pedal, allowing the one way valve to prevent any back flow, acting as though I had the valve closed.

Also another trick I discovered to speed up the process. I use a soft tube that is for fish tank aquariums, slide it over the bleeder valve and insted of closing the valve with a wrench I just tighten it with my fingers. Finger tight. It's fast to push, release, push release, without loosing the wrench on the valve, having to put it back on there, etc.

 

The squeeze bulb I bought today has a one way valve on it. I'm hoping I can hook it up to the bleeder valve and push and release the brake pedal, allowing the one way valve to prevent any back flow, acting as though I had the valve closed

Someone told me I could accomplish similar by only slightly releasing the stock bleeder valve. I tired it but it was way too slow. If you can you get someone to pump the pedal for you, it makes the task very fast. I was done in about 20 minutes. Also you don't have to store some oily gadget that is invariably going to leak and migrate fluid all over the place.

 

Yhea,

I'm willing to try new things, but my son is coming over just in case

I'll let everyone know how the different brake fluid works.

If it doesn't make a difference, I'm going back to the synthetic. So, I'll be doing this again.

 

The Results are in.

I flushed the brakes which had Valvoline SynPower fluid in them with Prestone DOT 3 petroleum based fluid and could feel a difference. However slight. It wasn't a, "Oh yhea, what a difference", it was more like, "Very Slight Difference".

I thought I had to push the brake pedal a little farther than normal. Farther meaning 1/8" or 1/4" more. Not harder, just a little farther.

In one day I used the Valvoline, then flushed with the Prestone and then flushed back again with the Valvoline.

I would say to use the Valvoline. Synthetics provide superior stability and is a better quality product. The difference was not very noticeable.

 

Thanks for the report. Did you notice how dark the fluid was close to the calipers?

This is probably spouting the bottle label...The higher boiling point and resistence to moisture would be an advantage for a synthetic, at a $1 or so more, I figure why not.

 

The first fluid flush last week was dark. It was replaced with the SynPower.

This week flushing the syn power out, it was just a little amber.

I also want to add that I've had a chance to drive the car to several locations and the brakes are solid. Maybe using them several times through an hours worth of city stop and go conditioned the fluid or something, but they feel just as good if not better than they did before the original flush.

 

Hi Attitude ,
after I bleed my brakes , I not totally sure but I'm not sure if my ABS
is working fully , I managed to screech my tires very slightly one day.
One of my co-workers claims the ABS unit may have to be reset .
He claims that the ABS senses change in line pressure and will
cause problems , I argued that the ABS works off the wheel sensor,
which is probably actually what we call an encoder at work .
and it varies the brake pressure thru a "electronic valving mechanism?

Does anyone know exactly how the ABS works on 1st gen. LS ?
My ANTI-LOCK brake light functions normally , so I don't suspect
there is anything wrong .

Thanks ahead of time.

 

Anti-locks ............The sensor on the brake tells the computer to release that brake of that rotor that is not turning .
.......This is just a simple explanation!

What sequence are you using to bleed your brakes and what about the proportioning valve ?...(one of my cars half of system that to be bleed with car off and the other half with car running)..........Just some info.

If there is proportioning valve in the system be careful!!!!!!!!!!

 

I don't know if the LS has a porportioning valve , but with
anti-lock barkes I don't really know since I don't have a
manual .I think the valve is to seperate the opposing sides , right
so that if pressure is lost , you don't lose all your brakes ?

My brakes feel stiffer than before , just that I get a slight squeal
out of the tires on dry pavement , I have yet to test it on ice or snow.

 

Mlevk, I have a 90LS and it will also squeal on dry pavement before the ABS kicks in. I suspect that this has to do with age and upkeep--although the previous owner was quite meticulous (air shocks were replaced, as well as AC compressor multiple times), perhaps he couldn't justify the expense of overhauling the entire ABS system, I dunno. I've always understood that ABS should sense when wheel lock is imminent and activate before the wheels lock. I've driven a 2000 model year Audi and the ABS never allowed the tires to screech...I chalk it up to old age and 'slow' sensors. 8) I would guess it's correctable if money were no object.

 

A very simple but effective way to bleed the brakes is to open the bleeder and let fluid running out by gravity. Add new fluid into the reservoir when the fluid level drops below the minimum line. Close the bleeder when you see clean fluid coming out. Continue on other bleeders until you finish all four. It's a slow process but you don't have to sit there and wait.
tvd51

 

How many days does that take?

Besides I don't think it works that way. I think there is a compression piston in the way in the Master Cylinder.

 

It usually takes couple of hours. I did it on several different cars, and it worked with minimum effort.
tvd51