Brake Master Cylinder Leak (1 Viewer)

[EyeCruzr]

PO installed "NEW" master cylinder couple months prior to my purchase in March.

Discovered slow leak between cylinder and booster.
Brake pedal feels fine, no observable loss.

1990 FJ62

http://babymame.com/picts/mc1.jpg

http://babymame.com/picts/mc2.jpg

What would you recommend I do?

1. don't know manufacturer of current MC, can anyone tell?
2. bore size? looks like a T100 MC or FJ80? so perhaps 1"?
3. should I buy an OEM or Aisin MC with 7/8? would pedal feel different?

Thanks

Ted

 

[tag3]

Pull old clean, check seal for a "hangup" and replace. See if still leaks.

 

[Spudman]

I just had a quick look on eBay and none of the MC's for the 60 series look like that, but I did find one for the 80 series.

If you type this number 260698175629 in www.eBay.com.au the 80 series is very similar if not the same.

Looks like you've got a 80 series MC

 

[EyeCruzr]

So if I wanted to replace, should I get

OEM/AISIN
a) FJ80 MC disc/drum
b) FJ62 MC

would the pedal feel any different if I went with a FJ62 MC?

I like the feel of the current MC, so perhaps stay with the larger bore?

Thanks

Ted

 

[CLove]

Seal

Echo, if it leaks against the booster, replace it. If the seal has a "hangup" it is likely damaged. IMHO good advice for getting out of a tight spot but not for DD or headin' out.
Looks like you have the 80 series MC. According to some previous posters there is a debate as to pedal feel. 60 with an 80 cylinder for the 4runner caliper mod (argueable whether or not it is an upgrade; Mudrak said skip it and just get new calipers) and the many configurations of 40 upgrades and mods is where most of the discussion arises.
I have also watched an old Indian mechanic mill a new booster to cylinder pushrod, which I believe was longer, in a FJ40 with an 80 series MC. So there may be a depth difference that would be important to know about. Maybe someone has some MCs laying around that they could mic.

C

 

[EyeCruzr]

Anyone know if the 80 cap is compatible with the 60's reservoir?

 

[beaufort-fj60]

did you try snugging the bolts a little?, maybe the po did not tighten them properly.

 

[CLove]

Anyone know if the 80 cap is compatible with the 60's reservoir?

No, the connector has to be changed between 60/62 & 80 MCs.

did you try snugging the bolts a little?, maybe the po did not tighten them properly.

IF you could seal this type of surface from hydraulic leakage, would only succeed in creating excessive backpressure on the booster. Not a good idea. This type of leak is how techs the world over know it's time to replace/rebuild the MC. It's not about the nuts that SECURE the MC, it's about the internal seal on the piston inside the MC that RETAINS the fluid and creates pressure assuming all other seals seal. Any leak of brake fluid is a loose compression FITTING, not fastener, or failed seal/line/valve/etc. But, if the MC isn't secured properly, improper alignment can destroy said seal, and correcting alignment will not fix the seal.

C

 

[EyeCruzr]

Bought a new Beck/Arney 072-8587 or Aisin Brake Master Cylinder specific for the 60 series via amazon for $97.00 and waiting on some SS brake lines from Georg.

But low and behold, my current reservoir cap is not the same diameter and won't fit the new unit.

So now Scouting for a new or used Cap. Anyone got one?

Ted

 

[the gimpey one]

I think i have one, will post pic asap.

 

[the gimpey one]

Sorry but mine will not fit. From a 84 fj60. Did not catch that you had a 62.

 

[EyeCruzr]

Sorry but mine will not fit. From a 84 fj60. Did not catch that you had a 62.

I bought this one, supposedly it's for a 60 and 62.



Need that cap w/ sensor

Geez, the price went down on Amazon to $93 today.

 

[Bama4door]

Geez, the price went down on Amazon to $93 today.

Just checked and it's $108 now!

 

[CLove]

Cap

Sorry but mine will not fit. From a 84 fj60. Did not catch that you had a 62.

IINM, Your 60 cap should fit perfect on his 60/62 MC. The cap should be the same for the entire FJ6x series.

 

[EyeCruzr]

IINM, Your 60 cap should fit perfect on his 60/62 MC. The cap should be the same for the entire FJ6x series.

As stated in the original post, looks like the po installed a 80 series brake cylinder and I was replacing it with a 60 series cylinder which requires a larger diameter cap.

As for the price or Amazon, look on the right hand side under more buying choices and SOLD BY AMAZON ($92.59), the 108 price is from car parts king with $8 shipping.


Ted

 

[norsk]

there was a post in the archives of using a Forerunner MC

https://forum.ih8mud.com/60-series-wagons/723890-master-cylinder.html#post8438865



dougbert