Can't get pressure in '83 V45 Magna hydraulic clutch

72texas350

72texas350

Been Around the Block
I have an '83 Magna that I am trying to get back on the road that is giving me nothing but frustration. I was having issues with the clutch slipping. After going though the system it was pretty clear that the slave cylinder was sticking, so I got a new one. I tried throwing everything back together yesterday, but now I can't get any pressure in the line.
I wasn't having any issues with bleeding the system before I replaced the slave. I have tried to bleed the line the way the manual says and just about every way I have found online. I have found that other people have had this same issue with the same bike.
I have taken the new slave cylinder off to check it for any leaks but haven't found anything. I have also checked all of the connections between the master, slave, and metal pipe that is in the middle of the two hoses; no leaks.


What might I be doing wrong?
 
I bled a V30 Magna clutch before and found that the angle of the MC on the stock bars made it so that the banjo fitting on the MC trapped air as it was positioned higher than the rest of the MC. I had to re-position the MC so that it was flat and then had the whole system bled in a minute or so. Make sure there are no areas along the route that allow it to hold air.
 
I thought that may be happening with the way that mc is placed. Did you permanently reposition the MC or just for bleeding the system.
 
I fill from the bottom-up. Take a CLEAN syringe (new, never used for anything but brake fluid) and fill from the slave up until the master is full.

Since your lines are already full and just needs to be bled, it should be easy to do so. I start with the master banjo then the slave cyl bleed bolt.

Turn the bars left to lock so that the banjo is the highest point. No need to unbolt the perch/cylinder.

Put rags around the handlebar and anywhere that fluid might drip from the banjo connection. Now apply a very very light pressure with one finger on the lever as you crack the banjo bolt. LIGHT pressure, this stuff will squirt out with force and straight into your eye, skin, and the paint. Keep applying a light even pressure as you turn the banjo bolt out very slowly until you just start to see some fluid come out. Tighten the banjo WHILE still applying pressure at the lever. You want to keep that light pressure in the line the whole time so that fluid is going out but air cannot get in.

Once the banjo is fully tightened, you can release the lever. The bolt is bled.

Sometimes I clamp the hose to increase pressure on the bubbles and they only have one direction to flow, out through the cracked banjo.

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I tried moving the MC to eliminate the high point at the banjo bolt. That didn't work. Next I tried pinching the line and bleeding the banjo bolt like Redliner recommended. That didn't do it either.
I still can't get any pressure in the line even though there isn't any more air coming from the bleed nipple on the slave cylinder.

Any more suggestions or ideas?
 
I'm not sure how experienced you are with hydraulic clutches, but you won't feel the same rock-hard resistance as brakes because the clutch has much more travel.

If it functions in engaging and disengaging the clutch, it's fine. If you aren't sure if you are getting pressure, stick a clamp on the slave so that the piston can't move at all and touch the lever. There's your resistance.
 
This is my first try with bleeding a hydraulic clutch, but I have ridden a few bikes that had a hydraulic clutch. There was much more resistance in this clutch before I emptied the system and took the slave off to replace it. Now there is no resistance other than the spring in the MC. If I take the slave off I can see the piston move out a little when I pull the clutch level in, but not much.
 
I am still not having any luck at getting pressure in my clutch line.
I've now rebuilt the master, just in case, and still can't find anything wrong with my lines.
Does anyone have any other ideas?
 
And when you clamp the hose closer to the slave, do you get resistance? Again, don't pull the lever in with a clamp on. Just use one finger.
 
Finally got it to build some pressure in the line. I think it ultimately may have come down to incorrect routing that built some high points that were trapping air. Oops ️.

Thank you everyone for the help!
 
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