850 master cylinder wanted

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Head

Head

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folks i got a machine shop to fit a 13mm re sleeve kit to my 73 850, now its drawing air and leaking fluid, got the full kit from Andover drill bit tap the lot,

as i pull the lever u can hear air , and the fluid is coming out near the front any ideas before i strip it down folks ,its only installed about a month ?
 
Head said:
folks i got a machine shop to fit a 13mm re sleeve kit to my 73 850, now its drawing air and leaking fluid, got the full kit from Andover drill bit tap the lot,
Click to expand...

"Andover" doesn't sell a re-sleeve kit?

Head said:
as i pull the lever u can hear air , and the fluid is coming out near the front any ideas before i strip it down folks ,its only installed about a month ?
Click to expand...

By "front" I assume you mean the lever end of the master cylinder?
 
Head said:
i seen this, just wondering what caused mine to leak after just a month tho, ?
Click to expand...

I don't know. I've been using the RGM sleeve kit for many years with no leakage.

I can only guess the O-ring is either faulty or perhaps damaged when it was fitted.
 
L.A.B. said:
I don't know. I've been using the RGM sleeve kit for many years with no leakage.

I can only guess the O-ring is either faulty or perhaps damaged when it was fitted.
Click to expand...
i will order it up its the cheapest solution for now thanks buddy
 
Its possibly not the piston seals that have gone but the rubber the insert rests on, or not enough pressure/sealant was put on the rubber washer and the sealant on the insert thread.


5. Place the nitrile washer in the bore of the master Cylinder, carefully press down to the bottom, wipe a little silicon sealer into the master cylinder thread. A very small amount as excess can block reservoir holes. Carefully slide the sleeve into the master cylinder, engage the thread and tighten fully. Tighten sufficiently to compress the washer slightly

Note from RGM

ALL THE MASTER CYLINDERS WE ASSEMBLE ARE BUILT AND BLED AND PUT ON A PRESSURE TEST JIG FOR A MINIMUM OF 10 MINUTES TO CHECK FOR LEAKS AND LEVER MOVEMENT

So look at the leak and try and see if its from the bore ie piston seal or from the OD of the insert.
 
kommando said:
Its possibly not the piston seals that have gone but the rubber the insert rests on, or not enough pressure/sealant was put on the rubber washer and the sealant on the insert thread.


5. Place the nitrile washer in the bore of the master Cylinder, carefully press down to the bottom, wipe a little silicon sealer into the master cylinder thread. A very small amount as excess can block reservoir holes. Carefully slide the sleeve into the master cylinder, engage the thread and tighten fully. Tighten sufficiently to compress the washer slightly

Note from RGM

ALL THE MASTER CYLINDERS WE ASSEMBLE ARE BUILT AND BLED AND PUT ON A PRESSURE TEST JIG FOR A MINIMUM OF 10 MINUTES TO CHECK FOR LEAKS AND LEVER MOVEMENT

So look at the leak and try and see if its from the bore ie piston seal or from the OD of the insert.
Click to expand...
thank u buddy, i bought a kit for 14 pounds this morning off rgm so will fit this when it comes and follow the guidelines thank u
 
kommando said:
Its possibly not the piston seals that have gone but the rubber the insert rests on, or not enough pressure/sealant was put on the rubber washer and the sealant on the insert thread.
Click to expand...

However, leakage past the sleeve seal at the inner end should only get as far as the first sleeve groove before it is vented to the reservoir (if not the first groove then the second), therefore, a leak from the outer threaded end should be a simple fluid leak in that area.
850 master cylinder wanted
 
i will dismantle later and give my results i hear air when i pull the lever and then few drops of pluid come out the lever side so i will chjeck later if i can thank u
 
Head said:
i hear air when i pull the lever
Click to expand...

As you are hearing air then it does sound more like the outer seal (O-ring) that's leaking to me although it could just be air expelled from the 'dust boot' as it compresses.
 
L.A.B. said:
As you are hearing air then it does sound more like the outer seal (O-ring) that's leaking to me although it could just be air expelled from the 'dust boot' as it compresses.
Click to expand...
good point i will check it out later could be air from booth but fluid is still getting out, and i have to pump the lever 5 or 6 times to get a bite
 
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Did the machine shop fit the sleeve or did you do that? The RGM sleeves are now supplied pre wrapped with PTFE tape so their included instructions that says to use 'a little silicon sealer' should be ignored. I,ve fitted loads of these sleeve kits and i much prefer them to the AN 13mm M/c as you can adjust the piston pusher to the optimum setting.
 
dobba99 said:
Did the machine shop fit the sleeve or did you do that? The RGM sleeves are now supplied pre wrapped with PTFE tape so their included instructions that says to use 'a little silicon sealer' should be ignored. I,ve fitted loads of these sleeve kits and i much prefer them to the AN 13mm M/c as you can adjust the piston pusher to the optimum setting.
Click to expand...
thanks dobba, when u say u can adjust the piston pusher to the optimim setting this is where i get lost lol, and more folk say line holes up for bleeding easier ,i have new resleeve kit on route so we will be back on to make sure its done right this time
 
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