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Sti shifter soaked in mineral oil

Hello. I just bled my brakes for the first time. I had to do it because I was changing my handlebar and both my original one and the new one have internal routing.

So I routed all the cables. I had to disconnect the brake housing, and put a new olive/insert in and reconnect. Then my brakes felt spongy, so I decided to bleed them. Never done it before though. But I had prepared myself for eventually having to do that. So I had everything for the job.

I bled the front brake which was the worst feeling. I did it three times and it still didn't feel firm. The third time I forgot to put in the plunger and all the mineral oil spilled all over my shifter. I cleaned it as thoroughly as I could.

Do you think that might be a problem? I mean the shifter. Also, the rubber cover on the shifter has become loose after having to pull it back and forth to clean all the oil. If I am gonna change that, then I still have to remove the cables again right?

There is one more thing. The left housing was not cut completely straight. So the insert didn't go in completely on one side. There was a small gap. Do you think that could have something to do with why it never felt firm again after bleeding? Could air be getting in there?

Just to add that I never bled the rear brake.

Sorry for the long post.



Posts

  • chelsea44chelsea44 Posts: 15
    edited 22 November
    Is there any danger of metal parts inside rusting?

    Also, I keep reading everywhere how important it is to get a straight cut on the brake hose so the insert is flush. But I can't find anywhere what can happen if it is not flush. Does it mean that the system is not tight and air gets in? The brake does work, it's just that you have to pull it almost to the bars.

    I don't know if to just leave it with a shop and pay whatever the mess I created will cost. I am out of mineral oil so I thought maybe I can get more and try to bleed the rear brake. If it works and it becomes stiff, then that probably means that the issue with the front is that the insert is not flush. I could order another olive/insert, cut a bit of the hose again and re do it on the front. I think I have enough hose left on the bike to be able to do it.

    Or it could also mean that I am not bleeding it properly.
  • david37david37 Posts: 417
    first off. DONT WORRY!

    clean the area with isopropyl alcohol and rags.

    the hoods on your shifter can be replaced if you feel necessary without removing cables or hoses.

    It is important to have a straight cut on the hose. If you have the available hose and a new barband olive then cut it again straight. and refit. Ensure the hose is pushed fully in as you tighten. if you have an 8mm crowsfoot flare you can attach your torque wrench 5-7nm for Shimano.
    You dont need a torque wrench though, nor do you need a flare wrench if you have a good quality 8mm spanner. If youre doing it manually do it slowly and you should feel the olive crush. thats when youve done it up enough.

    Finally this is exactly the sort of problem that people get when they start doing this job. in time you will find it a simple straightforward job that isnt messy and doesnt use gallons of fluid. You can buy a big box of original Shimano oil for just over a tenner and it should last for years, even after opening.
  • chelsea44chelsea44 Posts: 15
    edited 22 November
    david37 said:

    first off. DONT WORRY!

    clean the area with isopropyl alcohol and rags.

    the hoods on your shifter can be replaced if you feel necessary without removing cables or hoses.

    It is important to have a straight cut on the hose. If you have the available hose and a new barband olive then cut it again straight. and refit. Ensure the hose is pushed fully in as you tighten. if you have an 8mm crowsfoot flare you can attach your torque wrench 5-7nm for Shimano.
    You dont need a torque wrench though, nor do you need a flare wrench if you have a good quality 8mm spanner. If youre doing it manually do it slowly and you should feel the olive crush. thats when youve done it up enough.

    Finally this is exactly the sort of problem that people get when they start doing this job. in time you will find it a simple straightforward job that isnt messy and doesnt use gallons of fluid. You can buy a big box of original Shimano oil for just over a tenner and it should last for years, even after opening.

    Thanks for the advice. I had no idea that crowsfoot flare tool existed, otherwise I would have bought one for sure. The thing is, that my sensitivity is terrible when tightening things. So I have always done everything with a torque wrench, because I have a tendency of overtightening things. I even use a torque wrench for cassettes, threaded bb and cranks.

    This part I left out. But I also realised later that I overtightened both the bleed screws on the shifters and the parts you screw in when tightening the cable with olive. I also didn't put anything on the threads before installing. The first time I used an inner cable cutter to cut the hoses by the way.

    The front brake cable will have to be done again anyway, so I can grease the threads then and use a torque wrench to tighten. But the rear brake then. Is it possible to remove the screw and grease it without having to change the olive and insert again? Is it ok to use ptfe grease? I also have that park tool blue thick one.

    The reason I didn't cut the hose again(on the front) is because I didn't realise it wasn't straight until I had already put in the insert. And I didn't have another one.

    The hood on the left is totally loose so I have to change it. I am planning to order new hoods, bleed screws, pair of olive/insert, hose cutter and oil. O yeah, and that crowsfoot tool. And try do things right this time.

    Is it ok to use handsanitizer to clean the shifter?

    This kind of thing should be done on a less expensive bike first but I never had one with disc brakes before. So most other jobs I have learned on cheaper bikes.

    We'll see though if I have the courage to do this again or if should just leave it at a shop to save me the headache.

    It's crazy how complicated changing these internally routed bars can be.

    Sorry again for the long post.
  • veronese68veronese68 Posts: 22,937 Lives Here
    I wouldn't use hand sanitizer to clean it, that will probably leave some sort of residue. I don't think the end of the hose being perfectly straight is a big deal, the olive makes the seal so what happens beyond that is less critical. Unless you made a complete horlicks of it.
    Learn to not do things up so tight. Better a touch too loose and you have to nip it up later than to break something.
    It's not a difficult job, just take your time a be methodical.
  • david37david37 Posts: 417
    Wot Vernese said.

    the bleed screws need tightening to just .3 to .5NM which in practice means spinning it down till it hits the bottom and a virtually no more. unlikely to be anywhere near your torque wrench values. I have one at that level and i couldn't believe how little pressure that represented.

    Shimano publish their tech docs with step by step guides to the procedure, complete with pictures. here https://si.shimano.com/#/ you need the dealer manual.

    Select your product, print it off and take your time. think about it as a series of steps and do them one at a time. and take your time, if you get stressed take a break and have a cup of tea or a walk. then look back and say "thats actually a piece of pi ss"

    :)

    Alternately if youre in a club ask for help and someone is bound to show / help you.


  • I wouldn't use hand sanitizer to clean it, that will probably leave some sort of residue. I don't think the end of the hose being perfectly straight is a big deal, the olive makes the seal so what happens beyond that is less critical. Unless you made a complete horlicks of it.
    Learn to not do things up so tight. Better a touch too loose and you have to nip it up later than to break something.
    It's not a difficult job, just take your time a be methodical.


    I actually cleaned it with babywipes, but I'll have to buy some isopropyl then.

    I just went to the cellar now and loosened all the said screws a bit and made sure they are not overtightened. I don't think it's that bad then, given what you said about the olive. I used a hose insert driver to put in the insert, and it went in properly. The gap on one side wasn't that big, but it was clearly visible. And I did make sure I pushed the cable all the way in the shifter before screwing it in.

    If that wasn't the problem, that means that I just didn't bleed it properly. I only did the thing where you push new oil through the caliper. But I saw today a video where they put the hose in the caliper with a bag attached to it, and then he pressed the lever while loosening the bleed screw on the caliper, and then quickly closed it, so some oil came out. Then he pumped the lever a bit.

    I did try pumping the lever but I didn't do the part I described above. I never saw any bubbles come out though. So I don't know why the lever isn't firm. When I pull the lever, it gets to about 2cm from the bars. It's the same on both sides.

    The guy that did what I described above said that he had to do it 6-7 times until he was satisfied. Is that really required? The video was from RideJapan on YT.

    I am thinking that maybe I can get away with leaving the brakes as they are and try riding next year like it is. And then taking care of it after next season. The brakes do work fine after all. It's just that I have to pull the lever further. Would that be a bad idea?
  • david37david37 Posts: 417
    its a great idea.
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