Tapered grind cylinder texaco ??

Want To build me new texaco wit parts y have Not sur Witch engine cylinder is and wy y have new cylinder wit tapered grind ???? lost litle right now

David, the way that piston is worn halfway down its skirt tells me that it may come from a regular non-taper design engine, and the cylinder you put it into may be a taper grind design.

The 2 will combine into a tight fit combo, but the non-taper piston may  wear the taper cylinder faster, and ultimately the taper bore of the cylinder wears out into a non-taper geometry. I went through that in my history of COX engines, unfortunately.

How can you identify a tapered piston? I never knew about tapered pistons or cylinders when I disassembled dozens of product and Babe Bee engines and just bunching all the parts together. Do all thin walled cylinders have a tapered bore? Is that why some early number 2 cylinders perform well? I only knew of tapered bores in T.D. engines. The T.D. .049 engines I purchased in the early eighties had tapered bores according to the instruction sheets. Don't know the actual manufacturing dates of those engines although they did come in the crystal cases.

The cylinder identification table helps find engines with tapered bore.

https://www.coxengineforum.com/h23-cylinder-identification

In fact the way I see, apart from the early TeeDee 049...051 engines made roughly before 1974 (my TeeDee-s made before 1974 or so have, but later TeeDees do not have tapered grind) , the Killer Bee-s made between 1992 and 2002 also came with tapered bore. Given that Killer Bee-s also had slit exhaust cylinders, it may well be that David has a Killer Bee tapered bore slit exhaust cylinder, that he combines with a regular piston.

Whether a piston comes from a tapered grind cylinder is not easy to find out unless you have very fine gauges to measure the taper between piston top and bottom.. I would expect that normal, parallel contoured pistons will stick in the tapered bore cylinder and display wear marks seen on the piston David shows in his post, i.e. excessively worn half way down the skirt.

I never thought that the pistons were tapered on any of the years. The way the piston skirt is worn tells me that material needs to be removed from the skirt, and maybe a bit of lapping just above the exhaust port to maybe half way up the non tapered cylinder. Maybe reverse the piston in the bore to lap it, but do not go all the way to the top of the cylinder. Carefully of course. That way you pretty much have a tapered cylinder. You could do the lapping with a scrap piston too, but that way could fix both the P/C. Also alternatively you could take some 600 sandpaper and remove some material from just the bottom of the skirt. If the P/C fit is already loose then, well, sorry.

Wel m'y trouble is the piston cylinder new from cox buy couple monts from now after short run Find its old stock cylinder y tink wit new production piston correct me if wrong médalion .049 last production use that cylinder To ? Just want To build right type engines To Which it belongs y wanted To build texaco engines wit. ... m'y cylinder is tapered two bypas one boost on each no spi To very litle wit difrent casing ?? Tink y need new médalion piston right ???for right spec

Y want To build texaco engines for m'y modified ez bee fly in the Snow without silencer in Québec weather condition temp get very cold wit open exaust port engine wont run unles use silencer To keap heat inside cylinder y want Good performance slited exaust wit just litle deflector works very Good powerful below _15°silencer is best wit like _20°c temp tink texaco engines suit best for this particular condition and run tapered cylinder wit non tapered piston in cold parts react piston heat faster inside and cylinder stay cold litle result tight piston wile runing wear faster tink ?? Y fly m'y tigermoth in Snow storm lot of fun

Others would know more than me, but I thought all the pistons were virtually the same, except for the very early ones with the oil hole. The fit could vary.

DavidII1984,
I think running your engines in the cold weather is the problem, not the manufacturing of the part. In those cold conditions you would need to break in the new parts you installed. Make sure the engine comes up to operating temperature during break in and not too cold or too hot. Once the engine can run at a good rpm without sagging I would call it good. You could fill in the cooling fins with cord or copper wire to retain the heat. Cox engines normally run cold anyway. Some high compression heads come with less fins to keep operating temperatures up. The Texaco style 5 fin glow heads are used when running larger propellers, not good for cold weather. The Glo Bee head clamps had no fins, and engines using them ran fine. Running your models in the snow sure must be fun!

Yes coxaddict tink glo bee type wil be Perfect for that wil try To Find one wil use hi compression from the killer bee y tink y figure wat cylinder is same as the killer bee just Not cut modification To exaust it wil fit m'y need tink y have To break in inside To cold outside now just To late for him wil use difrent cylinder piston tink Not sure y try couple engines now outside try Find one Good runer for cold conditions

After Good search in the sceptre flight link hard To Find texaco test y Find it its found wit cox tee dee .09 rc.051rc
test look
Test found texaco engines duration inconsistent result of trouble wit production new matériel used change of ventury size y want more info on différence wit difrent ventury and back plate change rpm duration

Finally Find Good performance engine combo using over size ventury on texaco tank now wit spec of black widow old cylinder tapered wit two bypas no boost no spi now wit tuned pipe instal befor modification engines run 16000 max wil try and se différence y try wit new red mufler big drop rpm wit spi in hope To get same rpm now wit m'y modified tune pipe or gain in rpm y did change its exit for smaler size now same size of the collector look

Test wit just exaust collector 10 000 rpm wit tuned pipe 11 500 y have To make change To its compression tink tune pipe work just Not Good cylinder for it ??

Couple modification change ventury  now same size of back plate Bolt  exaust collector modification over size wit difrent back plate now texaco or black widow plastiques one ventury jet size larger than the one y used last test was runing bether like 13 000 rpm consistent Not tested my  engine after new modification is now instaled on m'y ez bee

Tink is redy for run now

Looks great, David..

Thank you is a spécial plane To me long time y have Not run m'y old ez bee crack in firewal and Bolt fixing the two part Front fuselage now fix

Look close y wont tel wat it is y build for atempt max rpm wit m'y tuned pipe hope its Not explode first test its Fine tuning at is best