Hey. I have a 1981 rx7. 12a 5spd. It's my dd right now but lately I've been having a few problems.

I believe my brake master cylinder is finished. Lately my brake pedal goes really soft. and when I press the brakes I see alot of bubbles coming up into the reservoir. So I figure its time to replace the master cyl. I'm just a little worried that maybe theres a problem with my booster also. Is there anything I can check to see if the booster is ok?

And secondly. I've noticed a small pool of coolant where the intake mani connects to the motor. I know theres coolant passages through the intake but is there anywhere that coolant goes through the carb? Or is it most likely seeping up through the intake manifold gasket..

Any help is greatly appreciated.. thanks.

 

have you tried bleeding the brakes to let any air trapped inside exit. and have you done any work lately that might have let air in?

the other question i'm not sure someone who know more about fb's show chim in on that one.

 

I haven't done any work that could have caused air to get in the brake system at all. I've only had the car for like 4 months and the p/o said he replaced the entire brake system.. I dont think he lied because all the lines and everything look new and arent siezed on. and it worked fine until a few days ago.. The only thing that I can think of is the temp around here was below 0c when i first noticed the soft pedal.

I'm getting the new master cyl tomorrow. Is there any way I can check my booster to make sure it's good?

I'm probably going to get a intake manifold gasket aswell. Do I have to buy the O rings for the coolant ports seperatly?

 

don't know of anyway to check the booster at the moment. it would be best to get O rings too. even if the PO did do brake work doesn't mean it was done right or everything that needed replacing was.

 

Brake booster failure = very hard pedal. Since your issue is a soft pedal, I think you are on the right track with the M/C.

Good luck



.

 

Thanks guys. The master should be in today..

I'm just having trouble getting the intake gasket from my local parts supplier... Is it dealer only or something?

I'm going to be doing the 20mm freeze plugs in the coolant passage. My question now is since these coolant passages will be plugged. can I either reuse the old gasket or make a new one without the coolant ports?

 

the only way u can re-use the intake gasket is if it's completely in tact with no tears or missing spots. i've never used gasket material to make intake gaskets so i don't know how well it will seal. and yes with the plugs u can do without the cutouts in the gasket for that.

 

Got the M/C and installed it... Brake problem solved. The only problem I had was the damn reservoir wouldnt seal onto the master properly... So I ended up using two intake clamps to squeeze it all together. It seems to have stopped the leak.... I'll see better tomorrow.

 

I actually found the intake gasket and Orings in stock at a local dealer... yay!

Installed the freezeplugs and then replaced the Orings and gasket.. no leaks... double Yay!

 

with the freeze plugs, there's no need for the O rings.

 

I put the Orings anyways just in case the freeze plugs somehow leak... plus they were only like $130 each..

 

I sincerely hope that was a typo!!! :0

 

$1.30... lol