Air Bubbles
#1
Tech Initiate
Thread Starter
Air Bubbles
When building the shocks, im having problems with air bubbles. I have the assembly built, the piston is at the very bottom, filled it up slowly with oil about half way, push the piston up and down slowly to remove bubbles, top off the assembly with oil, then slowly worked the piston up and down once again to remove the excess bubbles.
Im not sure how slow to work the piston, or maybe the process in working out the bubbles is wrong, but the oil contains a lot of small micro bubbles. Thinking that maybe these small bubbles wouldn't be a problem and out of curiosity, I finished the build by installing the little rubber stopper, capped it, pushed the piston to the very top, loosened the cap halfway, then retightened (which I take is to bleed the remaining air)... and once done, I can feel air as I work the shaft.
After work I am going to drain the entire thing, try to pour more slowly (not pouring slow enough maybe??), move the piston more slowly to see if that helps. As this is the first shock build for myself, any ideas would be great... or even a good tutorial (i am searching now myself).
Im not sure how slow to work the piston, or maybe the process in working out the bubbles is wrong, but the oil contains a lot of small micro bubbles. Thinking that maybe these small bubbles wouldn't be a problem and out of curiosity, I finished the build by installing the little rubber stopper, capped it, pushed the piston to the very top, loosened the cap halfway, then retightened (which I take is to bleed the remaining air)... and once done, I can feel air as I work the shaft.
After work I am going to drain the entire thing, try to pour more slowly (not pouring slow enough maybe??), move the piston more slowly to see if that helps. As this is the first shock build for myself, any ideas would be great... or even a good tutorial (i am searching now myself).
#2
Tech Champion
iTrader: (25)
do you let the shock sit a little before putting that cap on?
i put fluid in it(i just squeeze the bottle i never cared about speed) and once it to the top i work the piston up and down slowly put spinning the shock shaft at the same time idk if this helps but ive always done it. Then set the shock aside, do the remaining 3 and by the time youve down 3 the first one should be pretty air free. some people make stands for shocks to sit, i used to use stacked tires. you just want the stock stright up and down with the cap off
i put fluid in it(i just squeeze the bottle i never cared about speed) and once it to the top i work the piston up and down slowly put spinning the shock shaft at the same time idk if this helps but ive always done it. Then set the shock aside, do the remaining 3 and by the time youve down 3 the first one should be pretty air free. some people make stands for shocks to sit, i used to use stacked tires. you just want the stock stright up and down with the cap off
#3
#4
Tech Elite
iTrader: (12)
I typically fill the body about 1/2 full, run the piston close to the top of the oil level and go back down (very slowly; typically the slower you go the bigger the bubbles are). Top it off, run it back and down again. I usually dont need to repeat it again. If I do get the annoying little bubbles I flick the side of the shock body a bit (not sure it helps get them to the top faster or not but it makes me feel better ).
Obviously dont fill them all the way or they will hydraulic and be tougher to bleed.
Obviously dont fill them all the way or they will hydraulic and be tougher to bleed.
Last edited by madweazl; 09-28-2009 at 12:33 PM.
#5
If you're not letting it sit or the microbubbles aren't floating out use physics. Hold the shock body by the top and whip it around in big windmill circles like a centrifuge. The centrifugal force will push the heavier oil down and force the lighter air bubbles out.
#6
You have to watch when letting the air out under the piston. If you continue to go up and down with the piston after the air bubble releases you will get tons of little bubbles and will take forever for them to float up and go away. I usually let them sit for like 1/2 hour. I build them exactly like in the nitro house video link. It has worked well for me so far.