14 replies to this topic

[ginigwunkle]

ive got a laser/lasek ring compressor from bullseye motor spares.

its a ratchet type and looks very like this.... http://www.machinema...ring-compressor

when i compress the rings and put over the cylinder the rings pop out of the bottom and dont go in...

what am i doing wrong or is the tool no good?

[Chris_9866]

You just need to hold it firmly and flat on the top of the block then just knock then down gently with the handle of a hammer

[dklawson]

when i compress the rings and put over the cylinder the rings pop out of the bottom and dont go in...
what am i doing wrong or is the tool no good?

I'm not sure why this isn't working for you. I have a similar ring compressor.

What I do is to cinch the band up very tight on the piston/ring assembly with some assembly lube applied to the OD of the piston. (Make sure you leave a bit of the bottom edge of the piston skirt sticking out below the band of the compressor). Place the piston over the bore and insert the skirt up to the point where the ring compressor band is resting on top of the block. From there I use a wooden hammer handle and tap the piston downward into the bore through the compressor.

[ginigwunkle]

thats exactly what im doing, oil and everything, i just cant understand why it pops out right before the ring goes in....

[minimender]

Possibly not quite tight enough and not pressing the tool down hard enough when tapping the piston through.
Been there and it will go believe me.

[Ethel]

Are you sure the rings are the right way up? If you get the sense that the ring clamp is 'between notches' you could put a jubilee clip round it.

[ginigwunkle]

i think it may be my pressing, i snapped a ring last go so dont want to over do it this time!!!

shall give it another whirl tomorro!

Edited by ginigwunkle, 12 February 2008 - 10:03 PM.

[nordicmini]

try one of the rings in the block on its own and there should be a gap between the ends of the ring

also make sure the ring fit the piston ,that they finish flush. hope thats of some help

[Dan]

Three points come to mind, only two have been mentioned.

1 - Make sure the three layers of the spring steel are properly lined up at the bottom so that they are all flush. If one layer is sticking down lower than the others it will provide a gap for the ring to pop out into. Only wrap the rings (plus a little clearance below), wrap very little of the skirt.

2 - As said above, do it up tight. I mean really tight, tighter than you think it should be. Use engine oil, not assembly lube for pistons and ring packs because assembly lube can prevent the rings bedding nicely. It's actually too good a lubricant, initial ring bedding is very important and the assembly lube won't burn off very quickly which is kind of the whole point of using it in the rest of the engine! Just use loads of clean engine oil.

3 - Press down hard and (this is the important bit) squarely and evenly. If you are pressing hard you are actually less likely to break a ring as they will only break if they spring out and catch the edge of the bore as you push them.

Edited by Dan, 13 February 2008 - 02:20 AM.

[Bass Man]

Only done this once, on a 3ltr engine so the pistons were a bit bigger, the only thing I might add is you have to be positive when you push down, don't do it tentatively, I used a club hammer because the handle is thicker and the head is bigger to hold, and as Dan says, be liberal with the oil.

[ginigwunkle]

YYYYAAAAAAAAY there all in, should the crank be so hard to turn?i can only just do it by hand easier with socket on flywheel...

[Dan]

Did you give it a turn after fitting each assembly? Did fitting any specific one make it noticeably tighter? Does oiling the cylinders make it easier? If it's just moveable by hand when turning it by the taper then it's probably right. Did you Plastigauge the bearings?

[ginigwunkle]

not one made it a lot tighter, they got gradually tighter at each one,

i havent plastigauged but i micrometered the crank before and its well within tollorences, new bearigns too

[johnckeen]

I have the same problem, i dont have a chamfer on my bores though so its even harder!
Tried to get a tapered compressor from demon tweeks but they start at 75mm

I put mine in the vice with alot of cloth to protect the conrod then i turn the allen key as hard as i can, getting it as tight as i can, only then can i get it in, i have snapped 2 allen keys so far lol but fingers crossed no pistons rings snapped...yet

[01smartc]

We have just bought one of these bad boys for the workshop.. works really well, the dead blow really helps to get the pistons in!

http://buy1.snapon.c...amp;dir=catalog

Chris @ Smart Performance