Kyosho Cox .049 Mini Cooper Engine Assembly

I have no clue since I never owned one. Unless this engine was never disassembled before now, even as recently as 2015, we have no real guarantee that the engine was correctly assembled to begin with.

But the crankcase has a boss the starter spring would wrap around. I can see the classic dark aluminum stain on the case from the spring around the boss. Flipping the lower plate the other way would only drop the entire assembly by the amount of the lower plate's sliver of cylinder or can section...unless that same cylinder or can section also sits within the starter spring.

I'd like to see a picture of the engine partially assembled without the starter spring to see how everything lines up. I suspect the plate section of the lower plate would ride on top of the starter spring with the can section up inside the muffler body.

Again, no clue or argument...just a request for more visuals while we guess the OPs answer.

944_Jim wrote:I have no clue since I never owned one. Unless this engine was never disassembled before now, even as recently as 2015, we have no real guarantee that the engine was correctly assembled to begin with.

But the crankcase has a boss the starter spring would wrap around. I can see the classic dark aluminum stain on the case from the spring around the boss. Flipping the lower plate the other way would only drop the entire assembly by the amount of the lower plate's sliver of cylinder or can section...unless that same cylinder or can section also sits within the starter spring.

I'd like to see a picture of the engine partially assembled without the starter spring to see how everything lines up. I suspect the plate section of the lower plate would ride on top of the starter spring with the can section up inside the muffler body.

Again, no clue or argument...just a request for more visuals while we guess the OPs answer.

944_Jim: that's what i was asking robot797. He had one and posted the video, so he must know how it goes together. What i want to know is: where does the starter spring enter into the picture? it seems to be on the engine in the drawings shown way back above by GpBear. Look at the engine frontend closely. It looks like there is a spring wound around the area behind the prop drive plate. But how does it start the engine. or does it start the engine?

robot797 closeups please.

happydad

If you turn the bottom ring over then the manifold will not be held secure and i will move around and leak exhaust gas .
When I get the new engine from COX Canada , I will remeasure everything again and post all the findings .

I cant show pictures because I sold the car (in 2016 or 2018)
but I will look trough my archives because I should have some pictures somwere of a full disasembely
(hope the didnt got deleted in last years hard drive crash)
and I also strugled with the ring back then
but I can say with 100% sertentie the thin part will go at the bottem
because the start spring has to go under the exhaust

robot797 wrote:I cant show pictures because I sold the car (in 2016 or 2018)
but I will look trough my archives because I should have some pictures somwere of a full disasembely
(hope the didnt got deleted in last years hard drive crash)
and I also strugled with the ring back then
but I can say with 100% sertentie the thin part will go at the bottem
because the start spring has to go under the exhaust

robot797:  but what does the starter spring engage and how does it start the engine? Is there something down there that the spring engages that turns over to start the engine? I looked at the manual pages GpBear showed, but it is a bit confusing. It sort of looks like a transmission assembly. Or clutch assembly.

Can’t sleep, BP meds messing with my hip. Hurts like crazy.

Happydad I put in request for The Netherlands flag.

the the back of the flywheel is a catch
just like the sure starts

and for starting there is a rip stick that engages the flywheel gear
you pull it back winding up the spring
and you let it go and it should start

robot797 wrote:the the back of the flywheel is a catch
just like the sure starts

and for starting there is a rip stick that engages the flywheel gear
you pull it back winding up the spring
and you let it go and it should start

robot797:  rip stick? You mean the one that works twice, the falls apart because the plastic is decrepit?

 A lot of guys end up buying several because the break, fall apart or whatever. That is why I am looking for an alternative starting system for my Cox Stocker Car. Maybe a pull start. But I am having a lot of trouble matching things up and mounting the engine so the pull start cord end is reachable and the throttle-muffler doesn’t hit the fuel tank, and the glow head is free and clear to good air above the cat heatsink.

But what do you care, you are a marine, boat, guy aren’t you. We need more boat guys. I have a few drawings for hydroplanes for .049 from a forum member in Australia.

Later it’s 3:25a.m. Here PST. Happydad

yea this car uses a non removable ripstick
that doesnt break

robot797 wrote:yea this car uses a non removable ripstick
that doesnt break

robot797:  then does it really use the starter spring ir just the “cog” to engage the next assembly?

Hd

it does use the spring
becaue the rip stick is non removable
you pull it back it tentions the spring
and you releace the rip stick
the spring pull it back in and starts the engine

and if you have the removable rip stick
you pull it out and the spring gets tentioned
once the rip stick disengages the gear the spring does its work

GpBear wrote:Very usefull catalogue to keep for reference .
The problem is Cox does not show Kyosho,s muffler/throttle in any of its specs .

I am going to try to post a cople of pictures and a drawing later , if I can figure out how to on this forum .
Then it will be more clear as to what info I need.
Until later Ted
Here is a drawing from the Japanese manual , top right shows the engine assembly .
There you will see Kyosho muffler/throttle assembly .
The parts in question are the rings #60 above and # 95 below , these can installed wrong which will have an effect on Compression .
Later I will get some clear pictures and post them .
Ted

.

GoBear: is there a cross reference list with the drawing so I cam tell what 85 is? #6 is?.Etc.  really, #’s 5, 6, 7, 8, 53, 54, 55, 87? Those center around the “transmission” assembly.


Hd

this guy shows it kind of nicly

robot797 wrote:this guy shows it kind of nicly

Way cool. Or as the saying goes, “Noice”. Thanks robot797.

I love the way the rip stick looks like dual exhausts.


Now show us your new boat.  


Happydad

soon soon

Short Up-date , Waiting for a new motor from Canada right now , should be here soon and then will post here again .

balogh wrote:Great data!

If I had designed the COX cylinders I would have set the strict tolerance on the distance between the top dead center inside (where the head shim sits), and the bottom of the ring on which the cylinder bottoms out when screwed in the crankcase, because this distance influences the stock compression ratio. I do not think the lowermost fin on the cylinder had a strict position tolerance as that has no influence on the top dead center position of the piston relative to the horizontal axis of the crankcase. Hence the wide range of measurement data.Sorry if my explanation is confusing.

I don't think people took your explanation to heart and are overly wrapped around the axle concerning compression. All two strokes are piston timed to specific points in the cylinder so I fully agree with your explanation that the only real critical measurement is the inside one, and why the cylinder needs to sit tight to the crankcase to maintain that critical inside distance. Raise the cylinder without an associate longer rod and the timing of the ports is off. .27mm on a Cox .049 has to be significant. Either that is not the correct cylinder being used or something is funny with the sealing rings. Two top rings maybe???

I know he is waiting on a new cylinder but push come to shove, I'd be modifying that lower, or both rings to ensure that whatever cylinder is used, mates fully with the crankcase as Cox intended.

Mike

Think best way of replace cars cylinder is use somting like Texaco cylinder if impossible to find right part mini Cooper use same exaust than espo f1 gtp fit cars use hi compression head too

Old et cars like jerobee use dual port cylindre wit spi ring control dont use spi wit pipe like gtp

Cryhavoc wrote:

balogh wrote:Great data!

If I had designed the COX cylinders I would have set the strict tolerance on the distance between the top dead center inside (where the head shim sits), and the bottom of the ring on which the cylinder bottoms out when screwed in the crankcase, because this distance influences the stock compression ratio. I do not think the lowermost fin on the cylinder had a strict position tolerance as that has no influence on the top dead center position of the piston relative to the horizontal axis of the crankcase. Hence the wide range of measurement data.Sorry if my explanation is confusing.

I don't think people took your explanation to heart and are overly wrapped around the axle concerning compression. All two strokes are piston timed to specific points in the cylinder so I fully agree with your explanation that the only real critical measurement is the inside one, and why the cylinder needs to sit tight to the crankcase to maintain that critical inside distance. Raise the cylinder without an associate longer rod and the timing of the ports is off. .27mm on a Cox .049 has to be significant. Either that is not the correct cylinder being used or something is funny with the sealing rings. Two top rings maybe???

I know he is waiting on a new cylinder but push come to shove, I'd be modifying that lower, or both rings to ensure that whatever cylinder is used, mates fully with the crankcase as Cox intended.

Mike

Mike: we were stuck on the 2 rings top and bottom, that seemed to fit together oppositely. Thinking they were like puzzle pieces, opposites. I think GpBear tried the 2 rings top, bottom, everywhere they would fit.
But we never heard back if they actually fit together or not.

Happydad      

happydad wrote:

Cryhavoc wrote:

balogh wrote:Great data!

If I had designed the COX cylinders I would have set the strict tolerance on the distance between the top dead center inside (where the head shim sits), and the bottom of the ring on which the cylinder bottoms out when screwed in the crankcase, because this distance influences the stock compression ratio. I do not think the lowermost fin on the cylinder had a strict position tolerance as that has no influence on the top dead center position of the piston relative to the horizontal axis of the crankcase. Hence the wide range of measurement data.Sorry if my explanation is confusing.

I don't think people took your explanation to heart and are overly wrapped around the axle concerning compression. All two strokes are piston timed to specific points in the cylinder so I fully agree with your explanation that the only real critical measurement is the inside one, and why the cylinder needs to sit tight to the crankcase to maintain that critical inside distance. Raise the cylinder without an associate longer rod and the timing of the ports is off. .27mm on a Cox .049 has to be significant. Either that is not the correct cylinder being used or something is funny with the sealing rings. Two top rings maybe???

I know he is waiting on a new cylinder but push come to shove, I'd be modifying that lower, or both rings to ensure that whatever cylinder is used, mates fully with the crankcase as Cox intended.

Mike

Mike: we were stuck on the 2 rings top and bottom, that seemed to fit together oppositely. Thinking they were like puzzle pieces, opposites. I think GpBear tried the 2 rings top, bottom, everywhere they would fit.
But we never heard back if they actually fit together or not.

Happydad      

I should have explained the "tow top rings" comment. I couldn't really read the picture of the parts assembly that was posted but it seems the two rings have separate parts numbers. I was suggesting maybe he had two of the same thing by accident or whatever. Two top rings, two bottom rings, whatever, instead of one of each.

Mike

The 2 Rings that I have are different .
I am going to try and make a drawing of these rings with the measurements so that we all know what is what .
I will have that in the next couple of days along with some more closeup photos .
These rings where made by Kyosho for their model cars with their Throttle / Exhaust system to be used in conjunction with Cox .049 standard engine .

robot797 wrote:soon soon

robot797:    what about the 2 rings, 1 on top and 1 on bottom? What do you see there on the car that we don't see without the car? How do the 2 rings fit into the assembly? 1 upside down, 1 right side up? or what???

what is your insight on this issue of the 2 rings and how they fit into the whole assembly?

happydad                            
         I like to fly planes, run cars, I'm old.          USA. work together. Holland and Netherlands.

I am done recovering my hard drives
and I found the pics I took back in 2010
and its as I said it is
bottem ring is mounted the same direction as the top ring
because the start spring needs the room below the exhaust
I am gonna make a pic folder with all the pics I made back then
so that will be tomorrow (or later today for me because its past 12pm)