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Tillerman6

Still can't find the missing needle bearing - advice?

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Due to the home projects I had going (new boat shed) plus some upcoming  winter weather and the extended time it took to get a cylinder re-bored and plated, new piston, etc, I have not  actually started putting the engine back together. 

 

That  is because of one other nagging problem that is bothering me.  That is the missing needle out of the upper needle bearing cage that was part of the engine when I tore it down. 

I noticed that it was missing from the cage when I took the piston off the con rod.  There was a rag under the piston, but with my luck it  could have found it's way down into the cases under the flywheel.

I have looked everywhere for it, and I even got a fiber optic light cable down under the con rod between the flywheel weights to look for it, but I can't see anything out of the ordinary. I looked on the shop floor of course and tried a magnet as well. but got nothing.

So the next step is to split the cases and look for it inside.  This step is beyond my expertise and tool selection  so it would probably cost around 150.00 to do the inspection (I am guessing) but at least I would have the peace of mind knowing that there is no foreign object lurking in the cases waiting for the worst possible moment to come loose and ruin the new piston and bore that I have already spent 450.00 to get to this point.

If anyone has any advice or expertise in this area, I would be very glad to hear it!

 

 

 

 

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before you go to the trouble of splitting the cases, try washing the suspected roller out. First degrease the crankcase (so that the steel surfaces aren't sticky) then set up the bottom end with the crankcase mouth facing downwards and with an old bedsheet or something similar suspended loosely underneath and wash the crankcase out with a low pressure water jet (garden hose). If something gets washed out it should get caught by the bedsheet. Spray everything inside the crankcase with WD40 as soon as you are finished to get the water away from the metal.

Even easier would be to use a parts washing machine if you have one

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Don’t use water as suggested but get some diesel fuel oil. Fill the crankcase up halfway, hold engine well and agitate the mix, with a long thin artists type paint brush have a stir around as far as you can. Get a bucket and stretch a piece of cloth over the bucket, secure with string or elastic strap. Invert the engine over the bucket and allow all the diesel fuel to drain out. Look at the cloth strainer, if there’s no needle roller then get a thin magnetic screwdriver or just a thin magnet...thin enough to slip inside the crankcase recess. Test the strength of the magnet for its ability to grab hold of a piece of steel approx the same weight as a needle roller or slightly heavier. Have a dangle about inside the crankcase. I suspect that if you have dropped the needle roller inside then it might be stuck in one of the main bearings, this might well be on the flywheel rotor side as the strong magnetic field may be reaching into the crankcase and holding the needle roller to the inside. I do hope you have success but also, having noted your intention it looks like you want to use the old needle roller assembly.....please get a new roller bearing as with the work already done it makes sense. There are plenty of sources available to supply on the net.🙂👍S..t happens....I lost a clutch pressure spring when I dismantled the assembly, I hunted around in my workshop for hours (I like to think that my workshop is clean and tidy but inevitably you end up with ‘stuff’ stored about) I gave up and ordered new set...no bad thing anyway but annoying as the damned thing is in there somewhere...guess what? Having attempted to work out the trajectory of a small spring on take off and the potential ricochet effect off other surfaces without success I found said missing spring hiding one of the rungs inside my aluminium ladder 🤬Never mind new springs proved under compression test back to back that the original were indeed weak. 🙂

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I love the clutch spring story. It reminded me of when I was working on a TY250 kickstart a couple of years ago. The tiny spring that pushes on the ball went "zing" over my right shoulder at high speed and out the tilta-doorway to somewhere on the rough ground behind my workshop. I looked for about 10 minutes but they are tiny and it would have been coated in dirt so I gave up. A few months later my wife (who knew about the spring incident) gave me a metal detector for my birthday. Well I had a ball finding the most amazing variety of small metal objects out the back of my workshop, but no kickstart spring. I was telling a bloke at work about the spring story and was pleasantly surprised when he later gave me one of those springs that he had ordered along with a swag of other TY parts for a bike he was fixing up.

This searching business in a crankcase also reminded me of when I first pulled the cylinder off an OSSA motor. The cylinder studs are usually rusty and if you do it the normal way up there will always be rust particles fall into the crankcase as the cylinder comes free. To avoid this, I hoisted the bike up in the air, upside down, so that when the cylinder moved away from the bottom end, the rust would fall away from the crankcase

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I've managed to remove a dropped wrist pin clip by swilling out the crankcase with the normal mix of petrol/2T and blowing it out with compressed air from a can with a straw, the stuff used to clean PC keyboards and the like.

This canned air is really useful stuff and worth keeping in your tool box.

Edited by goudrons
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Ive managed to have a big end needle roller escape the engine via the exhaust (doing some damage to the piston and head on its way out). Granted the cage had failed, but it didnt stop me looking for it for a long time before i gave up

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3 hours ago, 2stroke4stroke said:

Are you sure the roller was not missing before you started stripping the motor?

This is probably likely.

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11 hours ago, feetupfun said:

I love the clutch spring story. It reminded me of when I was working on a TY250 kickstart a couple of years ago. The tiny spring that pushes on the ball went "zing" over my right shoulder at high speed and out the tilta-doorway to somewhere on the rough ground behind my workshop. I looked for about 10 minutes but they are tiny and it would have been coated in dirt so I gave up. A few months later my wife (who knew about the spring incident) gave me a metal detector for my birthday. Well I had a ball finding the most amazing variety of small metal objects out the back of my workshop, but no kickstart spring. I was telling a bloke at work about the spring story and was pleasantly surprised when he later gave me one of those springs that he had ordered along with a swag of other TY parts for a bike he was fixing up.

This searching business in a crankcase also reminded me of when I first pulled the cylinder off an OSSA motor. The cylinder studs are usually rusty and if you do it the normal way up there will always be rust particles fall into the crankcase as the cylinder comes free. To avoid this, I hoisted the bike up in the air, upside down, so that when the cylinder moved away from the bottom end, the rust would fall away from the crankcase

I once...and never to be repeated..lost my wallet, I had just checked under the bonnet of my car before leaving work for home. I used to keep my wallet in my jacket outside top pocket ( it was an anorak type jacket), which I was wearing. Having got in the car and driven about 10 miles I glanced down but couldn’t see my wallet, I patted the top pocket hoping to feel a bulge but nothing! My mouth went dry, I imagined phoning the credit card companies to put a stop on my cards, I imagined some tea leaf spending the £15 cash in the wallet then setting about the credit cards having a spending spree. I arrived home and shot upstairs ignoring my wife’s welcome, I desperately wanted to find that wallet on my bedside table....no not there! Bugger and double bugger!!! I went downstairs and explained what had happened, I put my head in my hands about to have a hizzy fit...bingo....look under the bonnet...hey presto...there nestling on the edge of the inner wing was my wallet...where it had enjoyed a 25 mile trip perched perilously close a void and potentially falling through the engine bay onto the road and goodness knows what would have happened to it....was I relieved...no more top pocket used for the wallet storage,oh no!🤷🏻‍♂️🤔👍

Edited by section swept
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13 hours ago, section swept said:

I once...and never to be repeated..lost my wallet...

No worries, your secret is safe with us!  :D

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On 10/17/2018 at 12:32 AM, section swept said:

Don’t use water as suggested but get some diesel fuel oil. Fill the crankcase up halfway, hold engine well and agitate the mix, with a long thin artists type paint brush have a stir around as far as you can. Get a bucket and stretch a piece of cloth over the bucket, secure with string or elastic strap. Invert the engine over the bucket and allow all the diesel fuel to drain out. Look at the cloth strainer, if there’s no needle roller then get a thin magnetic screwdriver or just a thin magnet...thin enough to slip inside the crankcase recess. Test the strength of the magnet for its ability to grab hold of a piece of steel approx the same weight as a needle roller or slightly heavier. Have a dangle about inside the crankcase. I suspect that if you have dropped the needle roller inside then it might be stuck in one of the main bearings, this might well be on the flywheel rotor side as the strong magnetic field may be reaching into the crankcase and holding the needle roller to the inside. I do hope you have success but also, having noted your intention it looks like you want to use the old needle roller assembly.....please get a new roller bearing as with the work already done it makes sense. There are plenty of sources available to supply on the net.🙂👍S..t happens....I lost a clutch pressure spring when I dismantled the assembly, I hunted around in my workshop for hours (I like to think that my workshop is clean and tidy but inevitably you end up with ‘stuff’ stored about) I gave up and ordered new set...no bad thing anyway but annoying as the damned thing is in there somewhere...guess what? Having attempted to work out the trajectory of a small spring on take off and the potential ricochet effect off other surfaces without success I found said missing spring hiding one of the rungs inside my aluminium ladder 🤬Never mind new springs proved under compression test back to back that the original were indeed weak. 🙂

I like the kerosine idea better than water.  And I had some terrible results from WD 40 with making things rust, so that one is out as well.  I will have to remove the engine from the frame in order to shake the cases well enough. I have some magnetic tape that might fit between the crank case weights and the inside of the cases.  I am not trying to use the old needle bearing again. I am sorry my sad story sounded that way.  I have a new needle bearing set and a new pin and piston and pin clips, new rings of course.  I might get real energetic and clean out the shop floor 100% into the driveway and see if anything shows up on the floor. that would be the easiest route if it works.  Just now I rotated the crank with a bunch of 2 stroke oil in the cases and I could not feel any dragging or friction. There is enough oil in the cases to coat the crank shaft weights as they dip into the oil, but they are not showing any signs of skuffing or disturbing the oil coating as the weights rotate thru the oil.

So now I'm wondering what is the down side of splitting the cases?  Are there any parts that would be hard to find/replace such as special gaskeIts or anything that would be risky to do?

And the other question is : Assuming that all the above sloshing and dumping does NOT turn up anything - then what?  I did not see anything fall into the engine, and there is still the possibility that the bike was put back together without the roller at some earlier point in time.  So would you just put it back together and fire it up?

I could put all the old parts back on it too.  I still have the old piston, cylinder and rings etc. That way if it goes ka-pow it will only be the old piston and cylinder at risk.  I would use a new upper roller cage with this scenario of course, but having a few minutes or hours on the engine without a failure would probably rule out the chance that there was still a gremlin lurking inside without exposing the new piston and bore to the risk of FOD damage.

 

 

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It never hurts to strip an engine down to its component parts and thoroughly inspect everything, especially an older machine. The crankshaft big-end and connecting rod could be scrutinised for signs of wear, or other damage. The crankshaft main bearings and seals for what they cost would be my first items for replacement. All of the gaskets are available from good suppliers, as are quite a few component parts. I’d do a search on wearing items and try to pin down any known weaknesses so that these can be dealt with effectively. Even though with crankcase well oiled it is not really going to tell you if the seals have gone hard or perished etc. which would give rise to engine running issues. A Clymer or Haynes manual would certainly be a help. Take photographs as you take the engine apart, if you choose this route, it will be good for reassembly and also for any future buyer. You never know you might even find that elusive😳 roller bearing!🙂👍

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On 17/10/2018 at 1:31 PM, goudrons said:

I've managed to remove a dropped wrist pin clip by swilling out the crankcase with the normal mix of petrol/2T and blowing it out with compressed air from a can with a straw, the stuff used to clean PC keyboards and the like.

This canned air is really useful stuff and worth keeping in your tool box.

I tend to keep to keep my compressed air in a compressor😉. Seriously though a can of compressed air is an ideal way to dry out water from the electrics, shift excess dust from an air filter or blow away crap from a joint area before removal and clear a tyre valve of grit etc before adjusting pressures. Good suggestion goudrons 👍🙂

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