Fire eater rescue help

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Okay i think i am getting closer!
I have attached 4 paint sketches, very rough...

I started with the piston closest to the top of the cylinder and then went around in the different positions.
Could someone please let me know where TDC and BDC are and what the left over positions are called?

This will make it crystal clear for me!

Andrew

image1.JPG


image2.JPG


image3.JPG


image4.JPG
 
lazy
The first picture is Top Dead Center.
The third picture is Bottom Dead Center.
The other two are just stages in between during piston travel.
Hope this helps.
Jim
 
Thanks Jim,

That is what i thought!
I might not have expressed myself correctly, pictures seem to get the message across a lot easier!

Now i have a good starting point to play around with the cam settings!

Thanks to everyone for their help so far!

Andrew
 
Hi Andrew,most flame eaters have a 120 degree cam duration so when the engine is at top dead centre the valve is full open
blazertdcbdc001.jpg

this is tdc
blazertdcbdc002.jpg

At 120 degrees from tdc the valve shoul snap shut on blazer you turn the crank clockwise but others can tun anti clock
showing the valve closed
blazertdcbdc004.jpg

showing the crank position at about 120 from tdc but not at bottom dead centre
blazertdcbdc003.jpg

hope this helps as I'm not very good with the p.c
best wishes Frazer
 
Thank you so much for those pics!!! ;D
Now i feel more confident that i will get it running!!

I now see the errors in my setting up....
I was way off mark....

Andrew
 
Andrew-

Sorry I didn't articulate how to do this well the other day. Sometimes, something that is clear to oneself is not so to others. Anyhow, Frazer made it clear. Somewhere in that range should get you close; then you'll have to play around and fine tune the cam setting.

A couple of other points not to forget- Make sure it has a good piston to cylinder fit and that the valve actually seals. Without those two things it won't create vacuum.

Bob
 
Hi Andrew,just one more thing to add to Bobs advice the valve needs to be able to lift very easily as the piston travels back up the bore so the valve plate only needs to be 2 to 4 thou thick with just enough set to hold the valve onto the cylinder head.When its right it should sound like an old man farting :big:
best wishes Frazer
 
Andrew-

How did you makeout with this engine? Did you ever get it to run?

Bob
 
Hi Bob,

I messed around with it a bit more without any luck...
Think i need to remake/thin out the valve more as it is still a bit thick.

As to some other tips, it does sound like an old man farting but does not want to run.

Also my time has been taken up with work, selling a lathe and trying to organize picking up my Clausing 8250 mill!
It has not been forgotten!!
Once i do some of the mods i will post another video of what is going on!
It seems to be extremely sensitive to cam positioning!

Andrew
 
Andrew, don't get discouraged these are not the easiest engine to get running.

As has been stated you must have got piston to cylinder fit. The piston should slide, by it's own weight, in the cylinder when the valve is open. When the valve is closed the piston should not slide in the cylinder.

The other critical issue is friction, have as little as possible. Use powdered graphite in the cylinder and valve face. For shafts and bearing surfaces the lightest oil you can get.
 

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