Brake fluid reservoir leaking (1 Viewer)

[Felde]

Hi need some advice, please.

My breakfluid reservoir started leaking where the stud joins the master cylinder. Obviously I rocked it too much in my effort to clamp a pressure- bleeding device to the lid.
- Anyone an idea how to disassemble this and how to seal it?

Neither workshop manual nor parts catalog clearly show a gasket or seal in this place. All I can see is part reference 47202T / 9056218151 called 'Ring'. Is that the seal?
How is the reservoir fixed in place? I suppose this 47231 is bolt with a bore that I need to undo from within the reservoir?
Anything else to observe?

Thanks for any advice
Best regards Ralf

 

[Zorlac]

Aisin MC Non abs J80
bolt on!
the best upgrade for any old 70 series.

Aisin Brake Master Cylinder WITHOUT ABS - 01/1990 - 08/1992

Manufactured by Aisin, Models without ABS - has fluid level sensor in the top cap

www.roughtrax4x4.com

 

[Felde]

Hi
Mhm. Maybe. Two Cons on it:
1. 100€ (compared to maybe 1.50 if I only need an O ring) and
2. Swapping brake components is illegal in Germany. You need an assessment and approval by the vehicle inspection authorities. Barely possible to get.
But thanks.

 

[FJBen]

You can get a rebuild kit and it has that rubber gasket that you need in it. Not sure who would have it in Germany, but Cruiser Outfitters here carries it.

You can take it apart and take it to a shop and try to match the O-ring. Maybe a bearing shop or someplace might have one.

 

[jblueridge]

That ring is listed as Discontinued and unavailable even with Amayama.
I found this related thread but it was posted long ago when you could buy the seal from a dealer.
Seal ring

 

[Felde]

Thank you for digging into it.
The thread you linked at least confirms this is the sealing O ring. I spoke to my local Toyota dealer: They confirmed this item is discontinued and unavailable.
I need to check back with them on Monday to speak to experts. Maybe we can make a plan. The same MC & reservoir was also in some more common Toyota models up to the late 90s, e.g Corolla.
An O ring should also be available from specialized dealers, provided the dimensions are known. To measure that I would however need to disassemble the assey. I will check out some options on Monday.

 

[JuanJ]

Hello,

Expanding the search to diesel trucks like the Dyna or the Daihatsu Delta may help.






Juan

 

[Felde]

Here is the solution:
1. Miraculous healing: After doing 300+ km on the weekend, my MC / reservoir connection doesn't show any leaking anymore.

Apparently the o ring was dislocated from pressing the reservoir in the seat when applying this clamping lid of the pressure bleeding device, and settled back into location when the MC got utilized.
Fingers crossed it stays that way

2. There are numerous repair kits for the MC available. Some of them only contain the piston seals and YES the o ring for the reservoir. Those are around 8 bugs.
Google parts number 0449360160.
Make sure you have the right MC diameter referenced. The original MC in my 1985 BJ73 is 7/8" / 22.2mm.
(Later models have 23.8 or even 25 like the J80 model recommended above )

 

[Felde]

If anybody happens to have the reservoir off, please measure that o ring and post the dimensions here.
Others and me will be graceful one day.
Thanks to all who jumped in willing to help.

 

[jblueridge]

Glad it took care of itself.

 

[Dprio34]

On the first image in this post of the entire Master Cylinder, there is NO part number listed for just the MC Cap. My MC works just fine, but I do get dust build up at the bottom of my cap / lid for the master cylinder after driving on dusty trails. The cap is just getting old & brittle. I was able to source a new cap for the clutch res 2 months ago, but If anyone knows if just the cap is available and part number for the MC, most appreciated. I need one w/o the wire / sensor. Thanks.