Jump to content
SAU Community

Recommended Posts

Ok so it's another thread on abs.

But as far as I can see no one has answered the ? or posted the pics as promised on what it looks like dismantled and/or how to replace the leaking seals.

The seals/orings at a guess let's say max $40 + brake fluid.

So why spend over $100 on another unit that's 2nd hand and will proberly start leakig some time soon.

Theres threads mentioning can replace seals but that's it, no one says how to and what not to disasamble.

SO HOW ABOUT IT, someone must know if it can be done??.

Edited by nobby
Link to comment
https://www.sau.com.au/forums/topic/362163-abs-leaks-r32gtr/
Share on other sites

basically no one here knows what to do

i tried throwing money at people no luck

one guy got all but some on here but was not able to get all

most people put in a non leaking used one

if you can fix all the seals make a how to as im sure many people would want to know

thanks for your time

im on a boat

I think successfully rebuilding is a myth,(i would love for someone to prove me wrong) I have read that one bloke had managed to change all the o-rings on his leaky abs unit, he even gave a parts list of what he used. Thread went dead when someone asked for a followup of if his abs had remained leak free 6months later.

I found a supplier that sold the EPDM seals that were listed for about $30 (2 sets) with all intentions of rebuilding the first leaky unit I swapped out of my car. Never bothered attempting it after I pm'd someone else that claimed they had tried it with the seals that were listed in the original thread and if I remember correctly he said it started leaking straight away, worse than ever.

I know brand new ones are silly expensive from Nissan OZ, but maybe research if the unit out of a TT300zx is the same. If they are that leaves you more to scrounge through at the wreckers or alternatively with the aussie dollar the way it is, buy one brand from the states for about $800. If i had money to burn I would probably do that.

basically no one here knows what to do

i tried throwing money at people no luck

one guy got all but some on here but was not able to get all

most people put in a non leaking used one

if you can fix all the seals make a how to as im sure many people would want to know

thanks for your time

im on a boat

Ok if I can find the time.

But first I'd have to pull it down and consider if possible to find parts.

If I have a win , well who's a lucky boy then!.

Wallets in hand and line up lol.

And RHD Japan today 26/4/11 $1396.76 + postage.

I think successfully rebuilding is a myth,(i would love for someone to prove me wrong) I have read that one bloke had managed to change all the o-rings on his leaky abs unit, he even gave a parts list of what he used. Thread went dead when someone asked for a followup of if his abs had remained leak free 6months later.

I found a supplier that sold the EPDM seals that were listed for about $30 (2 sets) with all intentions of rebuilding the first leaky unit I swapped out of my car. Never bothered attempting it after I pm'd someone else that claimed they had tried it with the seals that were listed in the original thread and if I remember correctly he said it started leaking straight away, worse than ever

That might have been me. I tried the seals listed in that thread (the list in incomplete BTW) and they didnt seal. The original seals are not circular in cross-section, and i'm convinced that generic o-rings, which is what is listed in the thread, wont work. Look at the seals in master cylinders and calipers - they're not round either. I would love to be proved wrong, but IMO if you cant find the exact seals its not worth the trouble.

If you do try it, the cap in the middle at the top of the unit had a large bolt head under it. Undo that bolt and it should come apart. Also make a note of which solenoid sits where, as when you pull it apart they will fall out.

Nobby, if you're in Sydney you can have the seals i have left over if you like.

Thanks alot for that info.

I'm up the rd, Wyee 1/2 hr past Gosford.

The seals would be nice but I'm sure your on the right track with em not being correct size.

The top cap is pressed on/in and not screwed in?. as it didn't want to move, and there was no way I would force it, if it screwed off lefthand thread or something!.

Can you get back to me asap about the cap as it's sitting on my bench awaiting my attention.

I'm a night shift worker on holidays so I intend to work on it tonight.

Yes it sounds silly that I aggree with you about seals, but not to pat myself on the back,I have a few ideas to solve the problem, but its a waste of time going there untill I open it and have alook and see whats realy involved.

Thanks Brad (nobby)

Thanks alot for that info.

I'm up the rd, Wyee 1/2 hr past Gosford.

The seals would be nice but I'm sure your on the right track with em not being correct size.

The top cap is pressed on/in and not screwed in?. as it didn't want to move, and there was no way I would force it, if it screwed off lefthand thread or something!.

Can you get back to me asap about the cap as it's sitting on my bench awaiting my attention.

I'm a night shift worker on holidays so I intend to work on it tonight.

Yes it sounds silly that I aggree with you about seals, but not to pat myself on the back,I have a few ideas to solve the problem, but its a waste of time going there untill I open it and have alook and see whats realy involved.

Thanks Brad (nobby)

Yeah cap is just pressed in. Good luck!

Thanks.

stripped down.

body cleaned.

passages blown out.

gotta clean the rest, and go from there.

looks in good condition, but as i suspected, aged seals that have shrunk/compressed over the years.

so it doesn't take a rocket scientest to figure out why the design has changed to a more mono block type to do away with the leaks.

a bit of usless info.

abs dates back to 1929 for planes, wikipedia.

I attempted it but never completed it due to having trouble sourcing the ridged EPDM O-rings at the base of each modulator.

What I've learned,

They're a c.nt to get parts for,

- Nippon Denso didn't want to help. At all. Perhaps some others who can write Japanese may be able to contact ND Japan for exact part numbers or specifications, exploded view, suppliers of O rings etc. I found a couple of chinese hydraulic places that would make the seals if I could get the _exact_ measurements, material hardness and some other things I wrote down somewhere and they'd mail them over in 8 or so weeks.

I think the modulators are tri-state. The ABS/4WD computer seems to send three signals:

Release Pressure - ~4 amps

Maintain Pressure - ~1.5 amps

Apply Pressure - off

From what I understand, normal ABS units have seperate valves for maintain and release - so 6 modulators for a 3 channel ABS and 8 modulators for the more common 4 channel ABS used today.

I spent ages at wreckers and could not find any ABS servo units that only use one modulator per channel. When I checked the wiring, most had may more wires and resistive circuits.

The accumulator and motor looks pretty standard fare - the motor drives two pistons on each side to pump the fluid back to the MC. I haven't torn up the modulators to see exactly whats in them.

I lost interest, they're cheap second hand so I got one :)

Yeah cap is just pressed in. Good luck!

I used a BFH and an 18" plumbers pipe wrench to get the cap off.

Underneath is a 12mm allen socket. You'll need a 1/2 or 3/4 drive socket with 12mm allen key head, big vice and a one meter breaker bar to crack it.

Bit more info

The base of mine was leak free, a little water found its way into the spring cavity area.

I'm fairly sure the leaks were coming from the three O rings either at the top or bottom of the modulator solenoids. Dont pull apart the base unless you really want to know whats in it.

There are very powerful springs in there so undo bolts one turn at a time to evenly distribute the load, until you have about a CM of gap then go for it with each bolt. Nothing springs out at a million miles an hour if you evenly reduce the load on the base plate.

Thanks Bozz.

Certanly looks like you spent sometime on it for sure.:thumbsup:

All good cleaned up and gotta sort the seals.

Think I've got the solenoids sorted in theory but to early to tell.

Giving the 3 pipes some thought.

These things should be able to be serviced simply to clean em out and regrease so your brakes work in tip top condition all the time.

Service recomend for eg:replacing brake hoses 4-5yrs but Nil service for abs.

You can play with the rest of brake system, so why not abs!.

Anyhow that another story.

Thanks again, nobby.

Edited by nobby

Bozz, just a thougt on what you said about water.

If water in base was from anywhere but rubber boot or alloy cap cover, you would have water in the abs unit and through the system.

Not good.

If abs was sound when you stripped it, then water only seaped in around boot and/or alloy cap oring, which should be an easy fix.

regards nobby

Edited by nobby

Hey nobby,

The water leaks in the base got in from underneath, not via the brake system. Everything in the hydraulic part of the servo unit was pristine.

Realistically, I reckon if the following kit were available:

Three ridged bottom modulator O-rings

Three top modulator O-rings

Eight pipe O-rings between the upper and lower body

That we'd easily be able to fix all leaks since thats where I think they come from.

If we can't get the exact specs from ND Japan, there's not really much harm in getting three or four different sizes for the modulator O-rings made up to see which size stops the leaks.

Nobby - how's your confidence level that you'll be able to fix it?

My second one has just started leaking like a sieve, which was triggered by bleeding after replacing the master cylinder..... If you're not confident I'll get a new one.

Nobby - how's your confidence level that you'll be able to fix it?

My second one has just started leaking like a sieve, which was triggered by bleeding after replacing the master cylinder..... If you're not confident I'll get a new one.

Hi mate, I am confident that I could fix the leaky solinod and pipe problem.

But Ive struck another problem.

I think the tiny cup seal of the pump pistons is leaking under vacume for the front side of abs unit.

I can bleed the rear on abs and remove air but not the front.

I am very sure the problem is where I mention, as the m/c is 2yrs old 5-7k, and front cal kits just installed and bleed ok so think air wont enter under pressure only vac when release foot or abs pump activates.And air rises straight to bleeder and is blead off or trapped in abs before it can be sent to cals and that abs is alot higher than cals and air remains trapped high explains my theory but hence I could be wrong and is simply still getting in around solinod/s under vac.

I holly aggree with you about bleeding m/c was cause of your abs leak problem, bleding cleared abs of fine patricals sealing unit.

Here's a TIP I learnt.

NEVER EVER BLEED BRAKE SYSTEM WITH VACUME PUMP, THIS REMOVES FINE PARTICALS THAT ARE SEALING SYSTEM.

my abs unit was fine up untill I vac bleed it.

Vac bleeding is a great way if you don't have help, is very easy and fast, you only need to seal bleed srews with thread tape which I did, and a TIP, good idea any way as fluid shouldn't leak everywhere when you bleed cals etc, or air sucked back into units when vac is present when your bleeding em, makes job easy especialy when 1 man bleeding. but I cant recomend vac bleeding if seal in system is suspect/old.

Edited by nobby

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



×
×
  • Create New...