1984 AE86 4AC issues

Swooki
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1984 AE86 4AC issues

Postby Swooki » Mon Jan 25, 2021 4:14 pm

Hello, I have a couple of issues that I need help with.

1) I replaced brake pads, rotors, brake shoes (drums), master cylinder, brake booster, and it is still squishy even after all this (I bled the brakes and master and everything.
What could be the cause?

2) Temperature and fuel gauge are not working all of a sudden?
What could be the cause?

3) What size is the rear drum brakes bleeder screw? I cannot find the right size.

davew7
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Joined: Fri Jun 06, 2014 4:34 am
Location: Michigan

Re: 1984 AE86 4AC issues

Postby davew7 » Tue Jan 26, 2021 3:58 am

It could possibly be the older rubber brake hoses, but I would still bet that you have air in the brake lines. Try using one of the vacuum brake bleeders.
Start at the rear longest brake line. Did you bench bleed the M/C for installing?
Davew7

Swooki
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Posts: 115
Joined: Wed Dec 21, 2016 1:48 pm

Re: 1984 AE86 4AC issues

Postby Swooki » Tue Jan 26, 2021 2:55 pm

davew7 wrote:It could possibly be the older rubber brake hoses, but I would still bet that you have air in the brake lines. Try using one of the vacuum brake bleeders.
Start at the rear longest brake line. Did you bench bleed the M/C for installing?
Davew7


What is bench bleed?

davew7
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Joined: Fri Jun 06, 2014 4:34 am
Location: Michigan

Re: 1984 AE86 4AC issues

Postby davew7 » Wed Jan 27, 2021 3:42 am

Bench bleed, is just filling the master cylinder on the bench before installing. It lets you angle the M/C out-let ports upward while bleeding so you do not have any air trapped inside.
Davew7

Swooki
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Joined: Wed Dec 21, 2016 1:48 pm

Re: 1984 AE86 4AC issues

Postby Swooki » Wed Jan 27, 2021 2:14 pm

davew7 wrote:Bench bleed, is just filling the master cylinder on the bench before installing. It lets you angle the M/C out-let ports upward while bleeding so you do not have any air trapped inside.
Davew7


Outlet port is the end where it goes into the brake booster correct and that side is facing up?
So all i have to do is fill it and tilt it upwards until when?

davew7
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Joined: Fri Jun 06, 2014 4:34 am
Location: Michigan

Re: 1984 AE86 4AC issues

Postby davew7 » Thu Jan 28, 2021 4:15 am

The master cylinder push rod end goes into the booster, that end should be tilted down. The outlet is where the brake lines attach. You pump the M/C until you no longer have any bubbles in the brake fluid, then install the M/C. Now that the M/C is installed, l would try jacking up the front of the car, then the back of the car, to see if you can get the air to travel to a bleed screw. If you started with air in the M/C, it is going to be a longer process to bleed the system. Davew7

Swooki
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Re: 1984 AE86 4AC issues

Postby Swooki » Fri Jan 29, 2021 11:46 pm

davew7 wrote:The master cylinder push rod end goes into the booster, that end should be tilted down. The outlet is where the brake lines attach. You pump the M/C until you no longer have any bubbles in the brake fluid, then install the M/C. Now that the M/C is installed, l would try jacking up the front of the car, then the back of the car, to see if you can get the air to travel to a bleed screw. If you started with air in the M/C, it is going to be a longer process to bleed the system. Davew7


There's actually no push rod on the M/C just a hole and the brake booster has a rod sticking out?

davew7
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Location: Michigan

Re: 1984 AE86 4AC issues

Postby davew7 » Sat Jan 30, 2021 3:50 am

You can use anything for a push rod, such as a punch. As long as it be pressed against the M/C piston.
Davew7

Swooki
Club4AG Enthusiast
Posts: 115
Joined: Wed Dec 21, 2016 1:48 pm

Re: 1984 AE86 4AC issues

Postby Swooki » Sat Jan 30, 2021 3:57 pm

davew7 wrote:You can use anything for a push rod, such as a punch. As long as it be pressed against the M/C piston.
Davew7


A screw driver will work then?

because I tried pushing it and it didn't go in.