You are correct with the scotchbrite pad.
Cyl De-glaze
what does everyone use to de glaze the cylinders on a rebuild, i have an oil burning issue at the moment and am going to put another piston, the new cyl and piston have 7 hours on them. i read tons about using a green scotchbrite pad and wd40 to do this,
anybody got any experiance with this method, doubt it will harm anything as the coating is really hard, should just remove all the baked on stuff,
sam
anybody got any experiance with this method, doubt it will harm anything as the coating is really hard, should just remove all the baked on stuff,
sam
1 - 14 of 14 Posts
What piston do you have now, what were/ are the ring end gaps... and how many compression rings, how did you break in the piston/ rings, and what oil did you use during break in and what oil are you now running??????
QUOTE (Terse @ Mar 21 2009, 10:55 AM) index.php?act=findpost&pid=760383
did not measure gaps as was new piston, rings and cylinder, are you ment to every time?
just rode it normally
use putoline semi all the time
the engine came apart after a few hours of use to fix an oil leak, i did not rep;ace the rings which is what the problem is, i just want to clean of any baked on deposits and do the job good this time
sam
stopck piston, 2 comp ringsWhat piston do you have now, what were/ are the ring end gaps... and how many compression rings, how did you break in the piston/ rings, and what oil did you use during break in and what oil are you now running??????[/b]
did not measure gaps as was new piston, rings and cylinder, are you ment to every time?
just rode it normally
use putoline semi all the time
the engine came apart after a few hours of use to fix an oil leak, i did not rep;ace the rings which is what the problem is, i just want to clean of any baked on deposits and do the job good this time
sam
I use a super fine grit sand paper and lightly go over it in a criss cross manner.
I would not use a full synthetic during break in. It can work to well and not the rings seat very well.
I would not use a full synthetic during break in. It can work to well and not the rings seat very well.
is the scotchbrite still ok to use, i think i read it was about 360 grit, i have already ordered some on ebay.
whats the deal with the end gap, i have replace the piston and rings around 3 times in my motor and 1 time in another yfz engine, each time i have never had an issue, untill i have re used them :icon_cry:
do i need to be doing this?
just had a look in the manual. if you have it to hand it will make it better to understand, it says the top ring clearance is between 0.20 and 0.30mm, but the limit is 0.55mm, does this mean it should be between the 20 and 30 but if its over 0.55 then your cylinder or rings is to worn?
what if the gap is bellow 0.20mm, how can you make it larger without damaging the rings?
sam
whats the deal with the end gap, i have replace the piston and rings around 3 times in my motor and 1 time in another yfz engine, each time i have never had an issue, untill i have re used them :icon_cry:
do i need to be doing this?
just had a look in the manual. if you have it to hand it will make it better to understand, it says the top ring clearance is between 0.20 and 0.30mm, but the limit is 0.55mm, does this mean it should be between the 20 and 30 but if its over 0.55 then your cylinder or rings is to worn?
what if the gap is bellow 0.20mm, how can you make it larger without damaging the rings?
sam
QUOTE (pondy @ Mar 21 2009, 02:38 PM) index.php?act=findpost&pid=760411
Yes.
is the scotchbrite still ok to use, i think i read it was about 360 grit, i have already ordered some on ebay.
whats the deal with the end gap, i have replace the piston and rings around 3 times in my motor and 1 time in another yfz engine, each time i have never had an issue, untill i have re used them :icon_cry:
do i need to be doing this?
just had a look in the manual. if you have it to hand it will make it better to understand, it says the top ring clearance is between 0.20 and 0.30mm, but the limit is 0.55mm, does this mean it should be between the 20 and 30 but if its over 0.55 then your cylinder or rings is to worn?
what if the gap is bellow 0.20mm, how can you make it larger without damaging the rings?
sam[/b]
Yes.
next week when i start this build i we see how they are, have you ever needed to make the gap larger? ifso i think i will use a small file
sam
sam
A file will work. Work in 1 direction outside to the inside.
well got my scotchbrite pads off ebay, ripped my motor apart doday and did my cylinder deglaze, it worked well just needs some elbow grease to get it sorted, i sprayed it with wd40 and scrubbed it in a x pattern for around 150 mins, then used carb cleaner and used paper towel to clean it all, its very shiny now
i think you could tell its buring oil, at the top of the cylinder there was a brown/black ring all the way around, was around 10mm think, i have never noticed this on any other rebuilds i have done before
if the colouring at the top of the cylinder normal or a sign its burning off oil?
sam
i think you could tell its buring oil, at the top of the cylinder there was a brown/black ring all the way around, was around 10mm think, i have never noticed this on any other rebuilds i have done before
if the colouring at the top of the cylinder normal or a sign its burning off oil?
sam
i also cleaned the combustion chamber of the head with the pad and its not spotless then i thought, cold this damage the valves at all? on some the edges have started to turn silver
The black ring at the top is normal, thats where the top compression ring tops out in the cylinder.
No your valves will be fine, think what they go through when ride... Or did you take them out? If so make sure you keep them in order!
What terse said, make sure you break it in hard if you want your rings to seat, no synthetic oil.
Quote from Mixxer:
the trick is to put enough presure on things like nitrided rings and nikasil cylinders to break them in to each other before anything microscopically "rounds off"
while edges are fresh and sharp is the best time to put the pressure on.....
the 3 gears of full throttle acceleration puts combustion pressure to good use by pushing the rings hard against the cyl walls....which will work to shave off "high spots"....
then the closed throttle decel....engine braking....puts a vacuum above the piston to pull fresh oil past the rings to help wash out the debris.....
the old adage of "break them in slow and they will be slow" comes from this sort of reasoning.... if you don't "shave and seal" when things are fresh and sharp....it will never finish to a perfect seal once things get slightly rounded....
No your valves will be fine, think what they go through when ride... Or did you take them out? If so make sure you keep them in order!
What terse said, make sure you break it in hard if you want your rings to seat, no synthetic oil.
Quote from Mixxer:
the trick is to put enough presure on things like nitrided rings and nikasil cylinders to break them in to each other before anything microscopically "rounds off"
while edges are fresh and sharp is the best time to put the pressure on.....
the 3 gears of full throttle acceleration puts combustion pressure to good use by pushing the rings hard against the cyl walls....which will work to shave off "high spots"....
then the closed throttle decel....engine braking....puts a vacuum above the piston to pull fresh oil past the rings to help wash out the debris.....
the old adage of "break them in slow and they will be slow" comes from this sort of reasoning.... if you don't "shave and seal" when things are fresh and sharp....it will never finish to a perfect seal once things get slightly rounded....
1 - 14 of 14 Posts
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