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Never heard of this. Old engine blokes any clues.

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2 years 6 months ago #225225 by cobbadog
I wonder if your compressor has any links to the McDonald Engines mentioned on here that are renown for spitting oil and blowing smoke for mosquito control.
Off topic slightly but last weekend we got an old B&S mower running again after years of being in a shed and under water in the last flood. We were told it will never run again. How WRONG she was, after a challenge like that we did get it running but last time it was here there was an awful lot of oil in the cylinder and in the muffler. It took a good 10 minutes to settle and run right.

Cheers Cobba & Cobbarette
Coopernook, The Centre of our Universe
Working on more play time.

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2 years 6 months ago #225235 by asw120
The catch can for the injector is there. This is the hardest part to find. Basically always missing.


Jarrod.


“I offer my opponents a bargain: if they will stop telling lies about us, I will stop telling the truth about them”

― Adlai E. Stevenson II

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2 years 6 months ago #225238 by Mrsmackpaul

Does everyone know what the CS stands for and how it works.?

C.S. is short for cold start

The handle shown in the third photo down that looks a bit like a tap handle sticking out the side of the head is to raise the compression by winding in the handle all the way in

This reduces the combustion chamber and raises the compression
This makes them start easy in sub zero temperatures
The handle is in the low compression position in the photo
This part isnt the most reliable part of the motor and most times they are just run on high compression, or at least thats what I have found
On the internal end of that handle is a double sided valve

Paul

Your better to die trying than live on your knees begging
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2 years 6 months ago #225239 by JOHN.K.
The JP engines with the changeover device are much sought after in UK.......a JP2 or JP3 can be worth up to 15,000 quid for the narrowboat enthusiasts...........exceeded in value by the early Gardners like the L2 or L3,and the LW2 and LW3.
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2 years 6 months ago #225245 by cobbadog
My CD uses a lever to change the compression ratio. A very positive system.

Cheers Cobba & Cobbarette
Coopernook, The Centre of our Universe
Working on more play time.

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2 years 6 months ago #225247 by 600Dodge
How does it work cobba? Does it just push the plunger into the chamber to take up space and increase the compression?

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2 years 6 months ago #225249 by cobbadog
I have never been inside here to know exactly b ut IO believe it to work as the other type mentioned, a two way valve, one way in increases compression possibly by placing the head and part of the stem of the valve into the chamber then to lower the compression you lift the lever and it then sits flush in the chamber. I have no manual on this engine and was fortunate enough to nut out the issues it had which were mostly based around the fuel pump and rack being seized. "I had that thi ng apart so many times thinking I assembled it wrong because when I operated the crank handleeee with the fuel connected it would only dribble out the end. Little did I know that was more than enough to atomise the fuel at the injector. I have an oil pressure issue with it now as this one being high speed tropical model runs a dry sump. Oil gauge says good pressure of 35-40 psi but the engine seizes now for some odd reason. I need to double check the flow from the sump to a filter to a resevoiur then pressurised at the twin oil pumps then through the engine. It is one of them jobs to get to one day.

Cheers Cobba & Cobbarette
Coopernook, The Centre of our Universe
Working on more play time.

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2 years 6 months ago #225250 by 600Dodge
I had a look at the screw type valves and thats what I came up with.

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2 years 6 months ago #225256 by JOHN.K.
The swirl chamber is like a figure 8 on its side......the screw in valve blocks off the chamber nearest the screw ........Im sure there will be a wiki for JP Lister with a drawing.
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2 years 6 months ago #225258 by Inter-Action
On yah John. That'a pretty good way of describe the low/high compression in the head of the CS. I was thinking i was going
to explain the valves operation. John has nailed it. I run mine for a couple of minutes then open up the screw valve. A small
hesitation in smooth running , a cough and splutter and away she goes. Smoothest running motor as you will ever get.
I will dig out my video of motor start / run and post when i am next at the Excel Blacksmith and Engine shed where some of
my engines are on display.
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