yeah i see that, i took the jb weld off gonna patch it up right now, took the cylinder head off there now and noticed there was a bit o play in the piston, is this serious ?, gonna take off the cylinder in a minute and check if everythings okay.
picked up my new blaster!!
- Thread starter darrencurry08
- Start date
have it all apart now and noticed that there's play side to side in the piston and the crank is this normal i cant remember the last time i had a cylinder off, heres some pictures.
this will help you figure out that piston to cylinder clearence/play...........
http://www.blasterforum.com/engine-13/how-measure-your-cylinder-diy-25767/
good time to replace that green paper base gasket too, before it causes you problems.
they've been known to suck into the base on more than one ocassion, like the piston manufactuers are behind their sales
use OEM yamaha or cometic only for best results
http://www.blasterforum.com/engine-13/how-measure-your-cylinder-diy-25767/
good time to replace that green paper base gasket too, before it causes you problems.
they've been known to suck into the base on more than one ocassion, like the piston manufactuers are behind their sales
use OEM yamaha or cometic only for best results
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have it all apart now and noticed that there's play side to side in the piston and the crank is this normal i cant remember the last time i had a cylinder off, heres some pictures.
Do I notice a thrust race missing from the lower big end?
There is one on the upper side but I cannot see one on the lower, maybe just the angle of the pics.
ill double check on that now, i dont see how there could be if it was never opened, btw Blaaster will i have to go up another jet size if i port the cylinder myself ? because im half way through it at the minute and need to know to tell the guy to give me a different size ??
They are dual stage reeds. It looks to me that the thrust race is missing to me too. Should have leak tested and compression tested before inspection.
big end of the connecting rod side clearence should be
.016 ~ .028 in. (.4 ~ .7mm)
shove it to one side and measure the gap left on the other end
measurement "D".......
it can be done with the crank still in the cases.
if a thrust washer is missing, it'll be way beyond spec
and if it let go when running, you wouldn't have to ask if it's missing, it would have left you know
Porting is one of the unknown commodities, some porting requires a jet change, whilst some others do not, play it safe and order 2 sizes above what you have got.
I have known irreputable shops to assemble a crank and leave out a thrust washer, and squeeze the crank halves up to take up the play.
I may run for a fairly long time, but the forces of friction will eventually have their way.
If that thrust is missing you have no option than to have the crank rebuilt.
I may run for a fairly long time, but the forces of friction will eventually have their way.
If that thrust is missing you have no option than to have the crank rebuilt.
Unless you have aligning tools and a good press then it is best left to a professional.
see way the thrust not there what actual harm could it do if it wasn't there ?, sure the rod cant move much anyway when the pistons in the cylinder ?
The thrust bearing is there to provide a friction relieved surface.
Without the thrust it will be steel on steel, not a very good combination.
It may run for yonks, but it may well not.
The end of the roller bearings may swell due to the added heat that a steel on steel mating may provide, causing the bearings to wear abnormally, eventually to sieze.
Failure of a big end bearing is not a pretty sight.
Without the thrust it will be steel on steel, not a very good combination.
It may run for yonks, but it may well not.
The end of the roller bearings may swell due to the added heat that a steel on steel mating may provide, causing the bearings to wear abnormally, eventually to sieze.
Failure of a big end bearing is not a pretty sight.
well when you look at it like that it is a pretty bad situation !, how much would it cost to get the thrust installed ?
that requires the crank to be pressed apart, and might as well just have it completely rebuilt while it is..........
Crankshaft rebuilds
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