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Dolby109
04-09-2013, 06:32 AM
Recently I swapped Q45 brakes onto my S13...and as usual it was a fiasco.
After finally getting the brakes on everything seemed good but a few days later the brake pedal went to the floor, brake fluid was gone. Eventually I figured one of the calipers was blown.

So I order a new caliper (AdvanceAuto only had 1 R-caliper left in the country) and I get it, put it on and power bled it (side note...they sent me the right part, but it was a Left Caliper...so I had to hold it upright with the valve on top to bleed it).

So I took it out for a ride and the brakes had good feel, no squishyness and if I hit them hard both front brakes would lock up. I figured I got off lucky.
But...today I drove it to work and realized that if I am sitting at a light the pedal slowly moves down if I keep pushing on it. I checked the fluid and its ok, so I assume this means there is still air in the lines?

So how exactly do I bleed the other lines? Presumably the air in the other lines is all at the top near the master cyl. I've never really had to bleed more than one brake. Can I just open up the bleeder valve, or do I have to power bleed each one? Is there a way to reverse bleed them (push fluid through the bleeder valve)?

S13CoupeLover
04-09-2013, 11:23 AM
Have a friend pump while you open and close. That sounded bad, lol. And you want to start from the furthest point from the bmc, so right rear, left rear, right front, left front.

Dolby109
04-09-2013, 11:40 AM
Ok, so what I described does sound like air in the lines?
Its been driving/braking fine, but if you hold the pedal it will slowly sink to the floor.

Mikester
04-09-2013, 11:46 AM
And you want to start from the furthest point from the bmc, so left rear, right rear, right front, left front.

Corrected. If you follow the way the lines are run, the left rear is actually the furthest point from the BMC.

Ok, so what I described does sound like air in the lines?
Its been driving/braking fine, but if you hold the pedal it will slowly sink to the floor.

Sounds like a combination of air in the lines and a left caliper where a right one should be ;)

BTW you can bleed them yourself with a Mity Vac if you have one.

Dolby109
04-09-2013, 12:51 PM
Ack...$195!?!? Mityvac Vacuum Brake Bleeder-MIT6830 - Brake Bleeders - Advance Auto Parts (http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_vacuum-brake-bleeder-mityvac_22988834-p?navigationPath=L1*14921%7CL2*15008%7CL3*15680)
Isn't there anything simple with like a tube and hand pump???

***Edit*** NM Mityvac hand pump kit...much better - http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_automotive-tune-up-and-brake-bleeding-kit-mityvac_22973736-p?searchTerm=mityvac

BlewByYou
04-09-2013, 01:39 PM
Ack...$195!?!? Mityvac Vacuum Brake Bleeder-MIT6830 - Brake Bleeders - Advance Auto Parts (http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_vacuum-brake-bleeder-mityvac_22988834-p?navigationPath=L1*14921%7CL2*15008%7CL3*15680)
Isn't there anything simple with like a tube and hand pump???

***Edit*** NM Mityvac hand pump kit...much better - Buy Mityvac Automotive Tune Up and Brake Bleeding Kit MITMV8000 at Advance Auto Parts (http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_automotive-tune-up-and-brake-bleeding-kit-mityvac_22973736-p?searchTerm=mityvac)

A friend :2f2f:

cotbu
04-09-2013, 04:30 PM
I use a one man bleeder system, it was like 5 bucks. I use it for bleeding the brakes and clutch. All it does is place the end of the hose in the fluid so air doesn't get sucked in when you pump the brake or clutch pedal. you can do this with a long enough hose and keep it submerged in fluid.

zooopreme
04-09-2013, 04:48 PM
I use speed bleeders. I bled my Q45's up front and S13 calipers in the rear by myself. Some people will tell you to steer clear from them because they tend to leak but that's because they probably over torqued them which resulted in damaging the part.

I've bled my entire brake system twice by myself and had them on the car for more than a year now with no leaks or any other problems.

S13CoupeLover
04-10-2013, 12:01 AM
Corrected. If you follow the way the lines are run, the left rear is actually the furthest point from the BMC.

Damn... Guess i wasn't paying attention to what i was writing. thanks.

Dolby109
04-15-2013, 04:05 PM
Ok, so I have the brake bleeder kit now which should help.
Only problem is my brake fluid level has gone down. The brakes still have pressure (and of coarse still slowly go to the floor).
I hit the brakes a few times while the car was idling and noticed it took maybe 1-2 ounces out of the reservoir....the thing is there is no brake fluid on the ground.

So does this mean I need a master cyl?
Where the hell is the brake fluid going?
Should I still attempt to bleed it?

jr_ss
04-15-2013, 04:33 PM
Youre losing brake fluid somewhere. It may not be your front calipers but your rears. Look at all the calipers, you'll notice a wet/damp spot on the caliper that has been seeping/leaking. Check inside your wheels, as the fluid has to drip and go somewhere if it is indeed your calipers. It may also be your master cylinder. Look on the brake booster, see any wrinkled paint and or wet spots? How about inside the cabin?

On a side note, if/when bleeding your brakes, you can take a piece of tubing, attach it to your bleed port and run it down into some fluid, this prevents air from getting back into that port and also allows you to bleed the brakes yourself. It also allows you to see the air being remmoved from the caliper you are currently bleeding. No need for speed bleeders or fancy pumps, although they do make quick work of it.

Dolby109
04-15-2013, 04:56 PM
We'll I hadn't even touched the back breaks, but I'd checked the wheels and there was no fluid.
So I finally have my wife start hitting the pedal and I notice I can hear the leak, and it turns out the line blown towards the rear of the car above the exhaust.

F...my....life.
At least a line is cheaper but that's going to be a bitch running it from the front.
Any advice on running a break line?
Where to buy? How much to buy? Fitting size?

Thanks

jr_ss
04-15-2013, 05:07 PM
Is it the rubber line or the hardline?

Dolby109
04-15-2013, 05:20 PM
Hard line...I just checked from a different angle and its the passenger side line after the junction that goes over the axle. So I'm thinking that must be...what 5' of line?

PeaceOnesxWai
04-15-2013, 06:00 PM
You dont even need to buy a bleeder tool to bleed the brakes.. Just use a foot or 2 of npt/vacuum line and a large bottle of brake fluid. Loosen the bleeder screw, stick the line in, take the other end into the bottle, hop in the car and step on the pedal 10-20 times, close off the screw.. repeat on all 4. You will need to refill the reservoir when it gets empty. Its a 1 man job, dont need friends.



You changed the front brakes but you only bleed the fronts.. air could have gotten into the system. Did a Q45 conversion recently too, thought i could have got away with it by clamping the hoses.. but air still got in. Redo from the whole system, problem should go away.

jr_ss
04-15-2013, 07:44 PM
Hard line...I just checked from a different angle and its the passenger side line after the junction that goes over the axle. So I'm thinking that must be...what 5' of line?

Just buy the factory line if possible. I may have missed it, but what chassis is this?

Dolby109
04-16-2013, 03:04 PM
Its on an S13, and its just the hard line that goes between the rear hose and the divider at the rear of the car. Probably 4-5 feet of line. I'm sure I could probably manage by myself but I have a friend who is good at brake lines coming over.

Silvia716
04-18-2013, 11:13 PM
you can get a vacuume bleeder from harbor fright for 20$ lol. make sure your bleeder valves are at the top of the caliper too a friend of mine upgraded his calipers and had the same problem but he had the calipers on backwards. the way i bleed witch works best for me is crack all the bleeders and keep filling the bmc, then i close them all off and vacuume bleed them all once and it usialy does the job.

Mikester
04-19-2013, 06:38 AM
Its on an S13, and its just the hard line that goes between the rear hose and the divider at the rear of the car. Probably 4-5 feet of line. I'm sure I could probably manage by myself but I have a friend who is good at brake lines coming over.

All your hardlines and the divider, take your pick:

TUBE ASSY-BRAKE REAR,RH - 240SX (S13) 1989-1994 :: Nissan Parts, NISMO and Nissan Accessories - Courtesyparts.com (http://www.courtesyparts.com/46315-tube-assy-brake-rearrh-240sx-s13-1989-1994-p-70883.html)

TUBE ASSY-BRAKE REAR,LH - 240SX (S13) 1989-1994 :: Nissan Parts, NISMO and Nissan Accessories - Courtesyparts.com (http://www.courtesyparts.com/46316-tube-assy-brake-rearlh-240sx-s13-1989-1994-p-70885.html)

CONNECTOR-BRAKE TUBE - 240SX (S13) :: Nissan Parts, NISMO and Nissan Accessories - Courtesyparts.com (http://www.courtesyparts.com/46313-connector-brake-tube-240sx-s13-1989-1994-p-70880.html?cPath=1418_1419_1515_1520&)

TUBE ASSY-BRAKE,REAR - 240SX (S13) 1989-1994 :: Nissan Parts, NISMO and Nissan Accessories - Courtesyparts.com (http://www.courtesyparts.com/46284-tube-assy-brakerear-240sx-s13-1989-1994-p-70878.html)

Dolby109
04-29-2013, 04:11 PM
Ok so I am having the worst luck.
I bent a new line and get it on, and then notice the rear pads are like stupid low.
So...I take the calipers off and rent a tool that should turn them and push them in at the same time. The problem is I cannot turn or compress EITHER REAR PISTON!?!
Is it seriously possible that both of my stupid fucking rear calipers could be shot a the same time?

All your hardlines and the divider, take your pick:
Thanks for the find Mike!

jr_ss
04-29-2013, 09:22 PM
Did you open your bleed ports when trying to push them back? Ebrake engaged?

Dolby109
04-30-2013, 01:04 PM
The e-brake was off, but I didn't open the bleeders.
As far as I knew fluid could move both ways in the system, and I have never had to open the bleeder to push back a normal piston.
I couldn't get either of them to budge at all...If there were pressure it would move but get harder I would think.

jr_ss
04-30-2013, 02:21 PM
Well, your problem is, the ebrake is integrated into the rear brakes. You'll have to screw the pistons back in, if I'm not mistaken. They make a tool to hook onto the piston to facilitate the procedure.

fliprayzin240sx
04-30-2013, 07:52 PM
http://images.superstreetonline.com/techarticles/130_22_z+acura_rsx_s_brake_install+compress_piston .jpg

Dolby109
05-01-2013, 02:26 PM
I take the calipers off and rent a tool that should turn them and push them in at the same time.
You'll have to screw the pistons back in, if I'm not mistaken. They make a tool to hook onto the piston to facilitate the procedure.
Reading is your friend. :p

Anyway I'm pretty sure they are just completely seized. I'll have to shell out another ~$120 to replace both rear calipers, and possibly rotors as well.

cotbu
05-01-2013, 02:41 PM
The new 40 community scares me sometimes. Our next generation of enthusiast suck at the most basic of shits.

Anyway, does the caliper ratchet out? if it does the let it pop out all by itself. Not seized, lube the thread, screw the piston back in. Same for the sliding pins (which is what usually seizes) take the pins out lube them up reinstall. bleed then bleed some more.

jr_ss
05-01-2013, 04:00 PM
Reading is your friend. :p

Anyway I'm pretty sure they are just completely seized. I'll have to shell out another ~$120 to replace both rear calipers, and possibly rotors as well.

I missed that part... I was fighting with myself whether the rear brakes had the ebrake integrated or not. I've had 300zx brakes all a round for the past 5yrs.

Either way, let them come out if they will like Cotbu said. Check the bores when they are out.

Dolby109
05-02-2013, 08:25 AM
Neither caliper would budge in any direction.
One of them has a broken boot too (looks like the boot stuck while the piston rotated).
The pistons are out so far the traditional square tool wont even fit in, or else I might have tried an impact 0.o

Would it be possible to lube the crap out of these with WD-40 or PB blaster to see if I could get it started, and then pull the piston out to put some grease in?