Brake Power Booster Push Rod adjustment

[Raf99]

So looking for some experienced help. From taking the old power booster out and putting the new one in I had to adjust the rod all the way in. Now with the new booster in the car nothing is set properly.

Can someone show me a picture of their adjuster nut/lock nut/pedal rod position under the dash?

I think I almost have it set correctly. The adjuster nut is all the way near where the threads end (closer to the pedal connection), but i still have about 1/4" until the master cylinder will make contact with the firewall without having to push the plunger in some. As per the manual with the pedal connected to the rod I adjusted the 17mm nut after loosening the "star" lock nut.

Now I have some lines and clear tubing attached from bench bleeding it, so i can see when I'm pushing the plunger in as I try to push it closer to the firewall. But I think I am correct that the plunger should not push in at all when tightening it to the firewall. (0mm - 0.0016mm clearance).


Thanks

[oyajicool]

Did you adjust the booster using vacuum pump prior to installing it onto the car?

[Raf99]

Did you adjust the booster using vacuum pump prior to installing it onto the car?

No. Wouldn't have mattered as I had to adjust the booster all the way in to make it squeeze in. So now in a position where ALL needs to be adjusted.

[oyajicool]

Running out of adjustment travel is telling me that the rod needed to properly adjusted prior to install. But, what do I know?

[Raf99]

Running out of adjustment travel is telling me that the rod needed to properly adjusted prior to install. But, what do I know?

One can still put a vacuum on it now. This part of the manual did confuse me tthough as I didn't see how it would affect the rod to MC clearance and when you install it there is no vacuum.

[Raf99]

Can someone show me a picture of their brake push rod and how much thread is visible? Under the dash....
I'm thinking mine is adjusted the total wrong way, as there's no pressure (thinking the booster rod is not touching the MC).

[Raf99]

OK. Really need some help on this. Hoping to make it to a dyno day on Sunday but its not going to happen if I can't fix this.

Basically I adjusted the brake booster all the way one way to squeeze it in. Now that it is in I can't see to get things set properly. Last night I took off the MC and realized the push rod was making contact with the MC 1" away from the firewall. < so the push rod was way too far in, but adjusting this is easier said than done as it is really confusing which way you need to turn things.

I have very little threads showing between the brake pedal pin and the locknut/adjuster nut of the brake booster. I have no pictures of the OEM one when it came out (it was adjusted all the way one way too to get it out). Some manuals advise to turn the rod to adjust and others say to turn the 17mm on the power booster itself (I think they both do the same thing).

Currently I get no pressure on the pedal and no fluid is being pumped anywhere. The last 1" of pedal seems to bite and give pressure.

[Raf99]

Ug, i'm so stupid. I have a 2000 accord I can look at for a reference.... but some help is still appreciated.

[Raf99]

Pretty sure I went from this...... , to this , to this , to this.....

[Raf99]

Still cannot figure this out. The power booster rod is sticking out too far and is making contact with the MC too early, leaving the MC making contact with the push rod when its still 1" away from the booster.

Is the rod length different between a ABS and NON-ABS power booster?

[Raf99]

145 views and not a single reply. Actually no mechanic, friend, or group I ask this question to has an answer. So I took it back out of the car again and the push rod definitely sticks out too far.

OEM


One i bought


Thus leaving the MC not being able to connect without pushing the plunger in (activating the brakes)



I'm going to order another one I guess. Sucks to spend $200 on this and I cannot use it. No amount of adjusting under the dash changes the rod in the power booster. Not sure if this is normal but .......... i just don't know anymore.

[laz93se]

Raf the master cylinder for abs and non abs are different, reference bore and stroke. Check to see if you have the correct one.

[Raf99]

Raf the master cylinder for abs and non abs are different, reference bore and stroke. Check to see if you have the correct one.

Reference where??

What I ordered was : ACDelco 14PB4349
https://www.rockauto.com/catalog/raf...ktemplate=true

http://www.carid.com/acdelco/profess...l#applications


It's starting to look like this is a ABS one, but I need someone to verify this.

[oyajicool]

Question and Answer Honda
Honda Repair Questions? Ask a Mechanic for Answers ASAP

Question: when changing the brake booster on 92 honda accord, what is the best way to know push rod adjustment length to be.

Submitted: 7 years ago.

Category: Honda


Expert Anser: ike replied 7 years ago.


HiCustomer my name isXXXXX for coming to justanswer.com.

The correct length of the booster pushrod is 116mm +/- .5mm, measured from the base of the booster to the center of the hole that the pin goes through where it locks to the pedal. This is for the pushrod that connects to the pedal.

For the pushrod that goes into the master cylinder, this can only be adjusted with a special tool from Honda, and a vaccum gauge. The best recommendation is that you measure the length of the old push rod, in mm, and adjust the new one to that length. The factory settings are from when the vehicle was new, and should correspond to the settings of the new booster.


http://www.justanswer.com/honda/1by7...-92-honda.html



Getting another unit may solve your problem since it is likely adjusted to factory spec. When I did this job for my son's friend's Accord, I didn't mess with that rod.

[Raf99]

Question and Answer Honda
Honda Repair Questions? Ask a Mechanic for Answers ASAP

Question: when changing the brake booster on 92 honda accord, what is the best way to know push rod adjustment length to be.

Submitted: 7 years ago.

Category: Honda


Expert Anser: ike replied 7 years ago.


HiCustomer my name isXXXXX for coming to justanswer.com.

The correct length of the booster pushrod is 116mm +/- .5mm, measured from the base of the booster to the center of the hole that the pin goes through where it locks to the pedal. This is for the pushrod that connects to the pedal.

For the pushrod that goes into the master cylinder, this can only be adjusted with a special tool from Honda, and a vaccum gauge. The best recommendation is that you measure the length of the old push rod, in mm, and adjust the new one to that length. The factory settings are from when the vehicle was new, and should correspond to the settings of the new booster.


http://www.justanswer.com/honda/1by7...-92-honda.html



Getting another unit may solve your problem since it is likely adjusted to factory spec. When I did this job for my son's friend's Accord, I didn't mess with that rod.

Ya, i read that too. I didn't adjust the push rod as I don't have the tool. So either this is a ABS unit (which explains why it is 1" larger) or its FUBAR.

Either way I'll just order a new one


Thanks guys