In need of technical information

[jmw]

I have a few technical questions about these changfa style engines:-

1) Does anyone have a cut-through diagram of the combustion chamber of an s195?

2) Is it true that the lube oil pump pressure/flow-rate can be adjusted?

3) What is the pressure and flow rate of the oil flowing through that pipe to the cylinderhead?

4) How is the injection timing adjusted?

5) How/where does the sump breath?

6) Some of these engines have counter balance shafts. What's the easiest way to determine if your engine has it/them?

7) How would you fit a stop solenoid to one of these? This question is really more about me not knowing how the governor/rack is controlled.

What's that pipe in the sump about? It appears to have a flared end situated at the bottom of the sump - hopefully this isn't where it sucks from.

9) How does the oil get back from the head to the sump?

10) There are probably 10s of millions of these engines in existence in China alone. Has anyone seen a workshop manual for one?

Mark

[mobile_bob]

1) Does anyone have a cut-through diagram of the combustion chamber of an s195?

yes i have a diagram or cutaway view, it is basically very similar to any idi engine with a hot insert

2) Is it true that the lube oil pump pressure/flow-rate can be adjusted?

no it cannot be adjusted as delivered, there is no pressure relieve valve and no filtration as implimented
although that all can be changed,  there are however some 195's that have both filter and pressure regulator
if you have one it will be mounted in the crankcase cover.

3) What is the pressure and flow rate of the oil flowing through that pipe to the cylinderhead?

it will be full system pressure, the oil pressure indicator is sort of a pressure regulator as well in that it has
a discharge port for the oil to be returned to the valve cover and to the crankcase when the piston is all the way up.

4) How is the injection timing adjusted?
with shim gskts under the injection pump, .004= ~2 degree's iirc

5) How/where does the sump breath?

behind the engine id plate on the front gear cover, you will find the governor shaft, inline with that shaft will be a hex plug
coming out of the gear cover that has a ~5/16" hole in it, this vents the fumes over the shaft, spring and aids in keeping
these parts lubricated.  sort of an elegantly simple solution to two issues in my opinion.

6) Some of these engines have counter balance shafts. What's the easiest way to determine if your engine has it/them?

as far as i know all 195s have countershafts, you can remove the crankcase rear cover and take a look if you like, they
are the two right under the cover.

7) How would you fit a stop solenoid to one of these? This question is really more about me not knowing how the governor/rack is controlled.

i wouldn't fit a stop solenoid, however i would fit a start solenoid, and adjust it for the proper travel to set my full rpm level
that way when power is removed from the solenoid the governor will have no bias and drop to no fuel. you will need to retain the
spring but attach it to the solenoid instead of the throttle lever bellcrank.

What's that pipe in the sump about? It appears to have a flared end situated at the bottom of the sump - hopefully this isn't where it sucks from?

there should be a screen pickup at the bottom of this tube?  if you don't have one then you should fabricate some sort of pickup bonnett
and screen assembly in my opinion.

9) How does the oil get back from the head to the sump?

the oil drains back throught the valve cover, then through the pushrod passages in the head and back into the crankcase, it is a very
unobstructed pathway.

10) There are probably 10s of millions of these engines in existence in China alone. Has anyone seen a workshop manual for one?

there are a few owners manuals, all basically the same, giving simple procedures for most everything, most torque spec's and clearances
parts lists etc.. certainly enough for the average mechanical type to get by with.

hope this helps
bob g

[jmw]

Bob,

Thank you. You certainly know your stuff.
Any chance I can see this cur-away diagram of the cylinderhead?

Mark

[mobile_bob]

let me see if i can scan the drawings and post them here
somehow my bet is the chinese steal the drawings from one another
so i would expect they would not come after me for copyright infringement.



if i can figure out my printer/scanner i will go ahead and do up the manual
and save it to a pdf file and post it here in the changfa section, or whereever
else it is most appropriate on this forum.

bob g

ps, don't know if i am an expert on the 195, but i sure like the design and for what its worth
the plain brg engine's can be fitted with a remote full flow filter and pressure regulator if you want
to remove a few plugs in the crankcase and drill tap a couple holes. this is something i will be doing
to my engines before they are put into full time service. i want full flow and bypass oil filtration and
a reliable pressure regulator, it is my belief that the fuel efficiency of the engine will likely improve
measurably if the oil pump pressure is regulated down to a sane level.

[jmw]

Bob,

What makes you think that the oil pressure is insanely high?
Do you think it is safe to reduce it?

If it is insanely high, do you think the excess pressure would be sufficient to drive a centrifugal oil filter? Flow rate would need to be high too.

Mark

P.S. This discussion forum is great - right up my street, as we say.

[mobile_bob]

its not unusual to see pressures  of upwards of 300psi when cold, and that is crazy in my opinion
while the pressure drops when hot some still maintain over 100psi which is unnecessary in my opinion

from what i have seen of the design it follows classic design, in that is has a Xdrilled crank and full pressure
big end brg lubrication, the main bushings are very large for an engine of its size, personally i probably will
be regulating my oil pressure to ~60psi cold and see if it will maintain 40 psi hot at 1800rpm.

if for no other reason but for the lack of off the shelf and relatively inexpensive pressure switches and sensors
it would seem like a good idea to explore reducing the oil pressure, and if you want full flow filtration using standard
spin on oil filters we got to get the oil pressure under 100psi when cold anyway or risk filter case failure and engine
damage.

bob g

[Henry W]

Hello Guys,

I have a copy of a Changfa S195 manual on a PDF file. The problem is it is 7.59mb.

I think we need to get in touch with the Admin. and see if he can post it.

Henry

[Henry W]

The Golden Flying Fish manual has more more specs written inside than the Changfa manual. We should try to get one copied.

Henry

[jmw]

Henry,

I'd love to see this manual, and am happy to take a large email attachment.

Mark

[Henry W]

The S195 manual was sent to you.
Check your email. It will take a while to load.

Henry

[jmw]

Henry,

Thank you. I got it and have read it.

I've got a few questions from reading it though:-

1) How often do you need to change the lube oil? The maintenance schedule says every 200 hours in one place and every 100 hours in the next.

2) Does the manufacturer really expect you to stuff burning paper into the combustion chamber through the glow-plug bung? I really don't think that would be very successful.

3) How do you get to the lube oil strainer? From the diagrams in the book, it seems that the sump would need to be removed by dropping it straight down. This would require plenty of space to be available beneath the engine.

Mark

[jmw]

its not unusual to see pressures  of upwards of 300psi when cold, and that is crazy in my opinion
while the pressure drops when hot some still maintain over 100psi which is unnecessary in my opinion

from what i have seen of the design it follows classic design, in that is has a Xdrilled crank and full pressure
big end brg lubrication, the main bushings are very large for an engine of its size, personally i probably will
be regulating my oil pressure to ~60psi cold and see if it will maintain 40 psi hot at 1800rpm.

if for no other reason but for the lack of off the shelf and relatively inexpensive pressure switches and sensors
it would seem like a good idea to explore reducing the oil pressure, and if you want full flow filtration using standard
spin on oil filters we got to get the oil pressure under 100psi when cold anyway or risk filter case failure and engine
damage.

bob g

Bob,

I would really like to try get a centrifugal oil filter working with these engines. Take a look at these:-
http://www.cbsenergy.com/coc-products.htm

The EL-1 seems to be the most applicable (it's their smallest). I have several of these and have used them on our Petter gensets.

I'd be happy to work with you in getting these units to work on these engines.

I've ordered a couple of s1100, but I've got to wait until the middle of December before they arrive and I can start playing.

Mark

[jmw]

Bob,

Also, how do you know what your oil pressure is?
Does your engine have a pressure gauge?

Mark

[mobile_bob]

no my engine does not have a pressure gage

my reference to the insanely high oil pressure comes form various
reliable sources that i have some faith in, and

once you see how the pump is built and recognize that it turns at crankshaft speed
instead of the more common camshaft speed of normal auto's, it is easy to see
how the pressure could be so high.

bob g