Stuck TD 0.9

Hello Fred,
I have just taken a look at the spanner that you show in the top of the picture. This will NOT engage in the top of the cylinder as you show in your first picture. The spanner is too thick to fit in between the black cooling fins and even if it were thinner. There are no flats on the lands between the cooling fins, so it couldn't be used to unscrew the cylinder even if I could get it to move!
I surmise that this must be an early TD 0.09 and that later ones had flats at the top of the cylinder to prevent the possibility of clumsy people damaging the corners of the exhaust ports and raising a lump on the inside of the cylinder, preventing the piston from going up and down!

Regards,

Andrew.

Hello Ron,
I omitted to say that I had tried the usual leather wrench trick. I finished up with the leather burning! I also tried a wrench with a plastic length instead of leather. This didn't burm but it smoked a lot and had me banned from the house!

Regards,

Andrew.

Well...since you are banned from the house...

and since you tried everything "normal"

1 part acetone, 1 part fresh ATF. Soak for a few days in a closed container. Take all the plastic bits off first.

Mix only what you need, when you need it, for this say 1oz each in a pickle jar.

This is one of the most potent penetrating oil concoctions I know of.

Phil

I use 50/50 acetone & trans fluid.

Thanks guys!
I have just prepared the Acetone/ ATF fluid mix, so it is wait and see. I will report back in a day or two.

Regards,

Andrew.

pkrankow wrote:...............
1 part acetone, 1 part fresh ATF.  ...snip...

This is one of the most potent penetrating oil concoctions I know of.

Phil

+1 on the effectiveness, but any unused oil must be kept sealed absolutely tight to keep the acetone from evaporating. I think the ultra-low surface tension of the acetone serves as a carrier for the thinned ATF. Once it evaporates from the part, it leaves minute amounts of ATF in the threads, etc.

I find that "fluids" help unstick stuck pistons, crankshafts and all the moving parts basically. A little heat speeds this up and I would always try and get the engine moving before attempting cylinder/backplate removal.

You have already got this far.

For an engine to have the cylinder a backplate this stuck, I would hazard a guess that it was tightened with some force while hot. Fluids will have difficulty penetrating threads that are stuck so tight. But good luck with the next soaking.

At this stage I would be resorting to HEAT and a heavy duty vice with smooth jaws and lined with aluminium - concentrating on removing the backplate first. It isn't easy - I use a very close fitting steel bar with a rounded edge. It is a foot long and I also apply pressure with the flat of a hammer to prevent it slipping.

Then I removed all the "moving parts" and soak and clean them while still warm.

The stuckfast cylinder is then VERY diffcult to remove without damage.

I take a piece of hardwood, drill a hole for the straightest part of the cylinder, cut it in two down the length of the grain - to be used as a clamp.

I also put a steel rod on one side that will fit right through the crankcase.

Then I don heat proof gloves and heat - heat - HEAT. Using the rod to carry the hot metal, cyilder hanging downwards (still wearing the gloves!) i clamp the cylinder in the aformention vice using the wooden clamp. (I don't apply heat from a torch around the wood)

Once mounted and tightened, I use a smooth jawed adjustable wrench (a foot long) and ........................ remove the crankcase from the cylinder.

All this is fraught with difficulty and at these extremes it is easy to cause damage. Patience, preparation and checking that everything is tight is key to success.

Take care!

Something to look at while waiting.  

https://en.wikipedia.org/wiki/Thermal_expansion

Just be careful as that concoction is flammable as all can be.

Phil

Hello Ian,
As well as the leather strap technique, I have tried a clamp along the lines you suggest and a vice with ally protectors. I finished up with a very bent piece of silversteel. I essentially did what you suggested for the backplate and using someone else to press firmly on the backplate / lever with a cobb end of steel (grooved to take the bar) Result was one bent bar!
I am going to machine off the backplate if the penetrating solution doesn't work. how to shift the cylinder without distorting the crankcase is going to be the challenge!
As a matter of interest, the wrenches on both Cox Int and Ex model engines are of the top type in the above photo. So not much use for this odd cylinder!

Andrew.

I did say this was the first stuck engine in over 50 years that has got me sweating. It has now become a personal challenge, whatever it takes!

Another "trick" that works sometimes... A can of computer "air" is mostly liquid and most all of them say to NOT shake or turn upside down...they are trying to prevent freeze burn liability....

Any way... what you have is a steel threaded cylinder stuck in a anodized aluminum crank case...odds are good the one or several times the cylinder was inserted and tightened the anodizing layer was compromised and now you have steel on raw aluminum and I bet a bit of dissimilar metal corrosion.. this micro layer of corrosion has an unusually high resistance to "breaking loose" and as you do NOT have a good tool the probability of damage is high

Used .09s are plentiful but a NEW crank case or Cylinder /piston set is "vintage RARE" and commands much $$$$

Get the correct wrench from Matt or Bernie
Get any and all new replacement parts you can find (there is a aluminum carburetor body available on e-bay)

Back to the canned air that is mostly liquid... If High Heat and the proper tools are not working try freezing the cylinder as a friend helps wave propane torch heat on the bottom of the crank case... heat will expand the female part of the crank case as cold contracts the male part of the cylinder

I have had very stubborn Cox engine dis-assembly issues and correct tools (bought or made) plus heat or very cold has always worked... pickling it in more chemicals (considering you have already used most of what we use) is not going to get into the tight locked threads you are working on

One more thing that works but you MUST have help... Put the crank case in a good vise with very flat lips that fully support the mounting lugs... but a brass or aluminum bar--- flat (I mean absolute flat) across the open top of the cylinder and have you or your helper give it a good solid smack down with a heavy-ish hammer

Don't keep beating on it...if all is square and flat, the ONE good solid smack might break the corrosion bond enough to get turning torque to break and loosen the cylinder....

There is NO good way to do this with the back plate as you will damage the nose of the crank case

I have ALWAYS been able to remove a stubborn cylinder...Back plates... hell I buy new ones and once on hand get ugly with beating the stubborn bugger out with a hammer and chisel if the tool slips and rounds the recesses (most of the time)

Good luck

Thanks Fred
I will give your suggestion a try after it comes out of the acetone / ATF mix. Never thought of giving a well supported engine a good thwack to break the bond between case and cylinder. Good idea...........why didn't I think of it. When I was working I had access to lots of liquid nitrogen and I would have used that instead of a freezing can. But if needs must, I will give that a try after the thwack! I have a freezer aerosol somewhere!
Neither Cox Int or Ex Model Engines have the correct tool for removing the cylinder. I need one of the old spanners, so unless someone has got one I can buy, I shall have to make my own.

Many Thanks,

Andrew.

tonsberg wrote:Thanks Fred
I will give your suggestion a try after it comes out of the acetone / ATF mix. Never thought of giving a well supported engine a good thwack to break the bond between case and cylinder. Good idea...........why didn't I think of it. When I was working I had access to lots of liquid nitrogen and I would have used that instead of a freezing can. But if needs must, I will give that a try after the thwack! I have a freezer aerosol somewhere!
Neither Cox Int or Ex Model Engines have the correct tool for removing the cylinder. I need one of the old spanners, so unless someone has got one I can buy, I shall have to make my own.

Many Thanks,

Andrew.

Any luck?

Hello Fred
I fished the 0.09 out of the acetone / ATF fluid mix. It must have been in the sealed jar for quite a few days. I set it up for your suggested thwack. I then wielded a home made tool, which is a little more substantial than the Cox one. I gave it a serious amount of force and it eventually gave up and came unstuck.
The back plate was another matter and that still wouldn't budge. So I took a rounded off chisel and using a lump hammer, rather gently, that too came undone.
There was no sign of a gasket on the back plate, I assume there should be one? Maybe that was why it was stuck way tight.
The conrod was OK in terms of big end, but a huge amount of slack in the ball joint. Once this was attended too, the whole engine was given a clean and a polish. The crank was an excellent fit and spun forever in the case, well a few times! A gasket was cut and new backplane installed and the whole lot put back together including an anodised aluminium replacement for the red plastic carb assembly, from a guy in NY State The latter was very worthwhile it doesn't leak like the nasty plastic ones. Test run tomorrow! or rather today but not at 5.30 in the morning!
Probably not worth all the effort put in, but at least another 0.09 saved from the bin! Thanks everyone for all your help, it helped me to keep my unbroken record of freeing up castor glued engines. I owe both Cox Int and Ex Model Engines an apology. They both have the correct tool for this older 0.09. A perusal at 3am in the morning with a foul temper didn't help!

Thanks again,

Andrew.

Andrew - There is no gasket as standard between the backplate and the crankcase.

   
Good one! Glad to hear the success.



Phil

Andrew,

Glad you got it freed up! Ian is correct there is no gasket beetween the crankcase and bacplate. Also, I noticed you mentioned a red plastic carb body. The TD .09 always has a black one, you usually find the red carb bodies on TD .051's

Ron

Take your intake off and heat up the engine with a heat gun. Works for me every time.

Ron,
You are quite correct about the colour being BLACK! I have not been able to get any sleep last night due to a very painful medical muscular condition. So I am not at my best and that is the second stupid mistake that I have made today! I shall leave my gasket in place, because I have had enough of Cox 0.09 backplates for the moment. I shall take heed that there isn't a gasket on the TD series backplates, I really couldn't remember!

Thanks for the corrections,

Andrew.

No worries Andrew, I hope you can get some sleep. Correct colors and what goes where is only minor stuff anyway. Take care!

Ron