Question: If a master cylinder were going bad, would the brake fluid level decrease - from leaks?
I ask because my '90 SE has decided not to brake very well for me. Almost 'feels' like the rear brakes are doing 95% of the work. The pedal is no harder, or easier to push than usual, but it is pulling to the right now. This unusual braking started without warning. Yesterday she was fine, and today I almost rear-end people!?
Any advice would be helpful (to say the least).
Thanks guys.

 

Yup. But check the entire braking system for leaks.

And get it fixed TODAY. You probably won't have ANY brakes by tomorrow.

 

See....there's the problem tho - I'm not loosing fluid. That's why I had to post - this is not making any sense to me? It's almost as tho both front caliper pistons have become lodged in their bore. No fluid loss, but no brakes? I don't get it?

Thanks for the quick reply tho Jeff. Appreciate it.

 

Check the interior right where the MS enters the firewall. Pull back the carpet/sound material and see if it's leaking there.

If no leaks then, you're going to have to take off the front wheels and inspect the brakes. Or maybe try bleeding the brake system(one wheel at a time) to see if that helps.

You could have a stuck emergency cable, stuck caliper pistons, faulty master cylinder or maybe massive amounts of goop in the caliper(I doubt it though)

I'm tending toward the ms though. If the seal is bad, maybe it's not generating any pressure.

 

You are in london, Ont(profile), right? Salt plays hell with brakes, everywhere. If it pulls, chances are a caliper is seizing - check for a hot disc after a short ride - the side it pulls to is usually the trouble side. Also the e/brake cable (assuming you use it) can also seize and give you the impression of extra rear braking. The car will not coast well in both cases - another check to make.
If you are not seeing a drop in the fluid level, you are not leaking. But if you are loosing braking force then suspect the master cylinder - this is a fairly common repair on our cars.

Finally, get in to a garage ASAP for a full brake inspection - before you find out the hard way what the problem really is.

 

The rear brakes aren't dragging, and the car coasts fine. Doesn't feel like a front caliper is sticking closed - feels more like both are stuck open. I'll check the rotor temp and if all else fails, I guess I'll have to take it to a shop - too damn cold here to do anything myself out in the driveway!
Thanks for all the input guys, will update you when I find the solution.

 

The rear brakes aren't dragging, and the car coasts fine. Doesn't feel like a front caliper is sticking closed - feels more like both are stuck open. I'll check the rotor temp and if all else fails, I guess I'll have to take it to a shop - too damn cold here to do anything myself out in the driveway!
Thanks for all the input guys, will update you when I find the solution.

 

Oops....double post - such an idiot...

Update:
Just had the car out for a spin, then checked rotor temp. It seems our cars have a dual, diagonal braking system because my driver rear and front passenger rotors were the only ones that were warm - the other two were stone cold.
Soooo....it's most likely not a caliper, or dragging e-brake. And seeing as the fluid level isn't dropping, I guess it's not a line. Sooooo....., that leaves me with the master cylinder.

Comment:
I researched these cars A LOT before buying one, and everything I read said they were sooooo reliable. Now..., I know all cars have problems, and I know cars with many miles that have been neglected have a higher failure rate, but....I am really running out of patience (and money!!) with this thing. I was soooo happy when I bought it (going from a rusted out '89 Cherokee), but now I just wanna kick in every body panel whenever I see it. I've been driving this car since about December 2002, and in that time I've replaced the CV joints, clutch, rear brakes, and I've had NO heat (in Canada no less...). I still need lower ball-joints, tie-rods, front brake pads, all 4 struts, and new springs. Not to mention this latest slap in the face - a master cylinder.
Now...., don't get me wrong....., I'm not *****in about Max's in general - just let'in off a little steam about my car in general, and possibly adding some entertainment value to this thread.
I guess my point is this... If you don't see me on the site in the near future...., I either died from some catastrophic vehicular failure....., or went broke try'in to fix it......, or just got fed up and sold'er...
I'll update you all on that too!

 

Before you get too mad, ALL of that stuff is REGULAR MAINTENANCE. That shoudl will have to be replaced on ANY car by about 100k miles. it all just happens to come in at one big chunk, as carmakers usually design a car's wear parts to go about 100-120k miles.


FIRST: bleed your brakes and see if that fixes it.

SECOND: check the pad thickness while you're bleeding the brakes. often the brakes will start to act drastically different on the last few (1-5) mm of pad thickness.

THIRD: Check the master cylinder.

FOURTH: Check the calipers for sticking. pull them off the rotor and use a C-clamp to mash the piston back into the caliper. if it doesn't go fairly easily, then it's frozen and you need to rebuild/replace the caliper.
rear calipers will require turning clockwise to get the piston back in because of the parking brake mechanism.

FIFTH: Take it to a shop.

 

Matt, thanks for the suggestions.
As for the other stuff - relax...
Like I said, I realize cars do this, and I was just let'in off some steam about mine in particular. Too say I've had unfortunate luck with used cars would be an understatement... And that has happened dispite taking them to be fully checked over before I bought. Just frustrated I suppose. Don't worry tho - I'll get over it.
BTW, in Canadian funds, a re-built master cylinder (w/ABS) is $108 plus $40 core...., and a new one (not from Nissan tho) is $200. (just mentioned that for interest sake)

 

Alright, here's the update I promised...
Turns out it was the master cylinder after all. Due to the cold, I decided to let the shop handle replacement. Brakes work great now!
Here's the rundown on cost (in Canadian funds):

$114.60 re-built master cylinder
$100.00 labor
$ 6.00 brake fluid
$ 33.09 tax

Total: $253.69

 

OUCH!!!! rebuilt master cylinder here is about $60.. an considering I'd do the work myself, that's almost $200 I'd save... yeesh.

 

Well Matt..., I have a sneaky suspision the weather is a tad warmer there. If it were summer here, I would have gladly done the work myself. Altough...? I must say, it is nice to drop it off broke, and pick it up fixed.
As for the price? Well...., the US to CA difference is something we're used to. Yeah..., it sucks, but there's nothing I can do about it. Whenever I go online to check-out prices, they're usually in US funds - so to estimate a CA price, I usually just double it. As you can see with the master cylinder - that's a pretty accurate way to do it.
Next on the list of repairs will be ball-joints and wheel bearings...

 

Occansionally A Master cylinder will develop an internal leak causing poor braking and no fluid loss.

 

Matt, from the picture in your profile, I'm guessing you're from the US. If that's the case US$60 is CDN$116 (give or take)!!!!


Martin 90SE 5sp

 

I've been driving this car since about December 2002, and in that time I've replaced the CV joints, clutch, rear brakes, and I've had NO heat (in Canada no less...). I still need lower ball-joints, tie-rods, front brake pads, all 4 struts, and new springs. Not to mention this latest slap in the face - a master cylinder.
Now...., don't get me wrong....., I'm not *****in about Max's in general - just let'in off a little steam about my car in general, and possibly adding some entertainment value to this thread.
I guess my point is this... If you don't see me on the site in the near future...., I either died from some catastrophic vehicular failure....., or went broke try'in to fix it......, or just got fed up and sold'er...
I'll update you all on that too! [/B][/QUOTE]


Don't regret your purchase. Remember it's age and factor that in.
You will be hard pressed to find a car with as high a "fun quotient". Hang in with the suspension repairs until the weather is better and do the work yourself - the max is easy to work on - relatively speaking.
Also, I would do something about your "expert opinion" the next time you check out a car. Yours has way too much wrong with it considering how long you have had it. Did you have it certified "properly" or did you go the low cost "friend" route? If it was legit the certifying garage may want to cover some of your costs.

BTW is yours a 5sp?

Martin '90SE 5sp

 

Sssshhhh... My ego might hear you and figure out I forgot to take currency exchange into account.

 

Martin, yeah mine's a 5-spd. The clutch was dy'in when I bought it - I knew that. But when the CV joints went, I figured I may as well do the clutch at the same time - no sense paying the labor twice ...
As for the rest of my problems? I really believe a lot of it can be associated to the previous idiot who cut the springs instead of lowering the car properly. I know age is a factor, but it's difficult to remain calm some days when everything seems to be failing at the same time. Hey...., if I were wealthy, and/or it were summer (do the repairs myself), then it might be a different story? Like I said before tho - don't worry...., I'll get over it.
As for getting my cars checked-out by an expert, I've always taken it to reputable shops.
On a positive note.... If I keep going at this rate, mechanically, the car should be in near perfect condition by the end of summer. I guess that's something to be happy about??