Changfa running in Listeroid territory :-)

[flywheel]

After increasing flywheel mass and retarding the injector timing the problem I still see with really slowing down the Changfa types is in maintaining the functionality of the internal oiling system.

In the case of my JD175A I have an oil pump that sucks oil off the bottom of the sump and the pump pressurizes two passageways.  One feeds oil to the rockers and valves where it returns to the sump through the pushrod galleries.  That will work OK as long as the oil pump can move oil.  The other passageway is designed to fire a solid stream of oil sideways towards the crank throw where for a few degrees per rotation a hole drilled into the side of the throw picks up some oil and through a slant in the drilling angle of this hole in the crank and centrifugal force, it feeds it under pressure into a feed hole cut into the lower rod crank journal to lubricate the lower rod bearing in the usual way. When you remove the con rod the hole in the journal looks like any pressurized automotive crankshaft setup.  When the engine is hot and the oil is thin the oil pressure in the gallery on the output side of the pump drops like a rock from about 6 PSI cold to less than 1 PSI. I have added a pressure gauge and external spin on full flow filter so I know what the pressure is.  That stream being shot at the target hole in the rotating crank may start to droop and miss the target at some low RPM.  If these engines had sleeved bushing bearings on the ends of the crank  the crank could be truly pressurized by a cirumferencial slot around the crank within an end bushing sleeve bearing near the oil pump (timing cover side).  Being that most of these engines use ball bearings on both ends of the crank, it is more difficult by design to pressurize a passageway internal to the crankshaft.  The method used in my JD is rather clever.

In order to increase the lubrication to the camshaft, the wrist pin bushing, and even the main crank ball bearings that all get lubed merely by splash from what is hurled off the rotating crank I added an actual diper to the lower of the two big end con rod bolts.  This mod worked out very well. There is a LOT MORE oil being hurled around now where it can do good.

Perhaps it would be possible to add a restrictor orfice to the hole in the block where the oil jets from towards the crank throw target hole.  This would up the hot oil pressure by a large margin if sized appropriately and produce a real jet of oil under slower RPM conditions.  How the big end bearing of the con rod gets lubed in my Changfa 1115 is still a mystery to me but I suspect it is the same design as most of the modern 195 engines.

I saw a photo of a 195 engine once that appeared to use bushings, not ball bearings on the outer ends of the crankshaft.  In that particular engine I suspect it possible to pressurize the crankshaft the same way it is normally done in a common automobile engine.  I don't think many of our China diesels are made that way.  Ball bearings seem to be much more common.

All of the china singles I have had apart have a ball bearing on one end of the crankshaft and a sleeve bearing on the other end.  Oil is fed under pressure from the oil pump to the sleeve bearing where it enters the crankshaft under pressure. The sleeve bearing may have a groove all around its od where its pressed into the block to receive oil under pressure. I have not had one of my 1115's apart to see if they are the same.
                                                                                                                       flywheel

[mobile_bob]

my changfa s195 has bushing brgs at both ends of the crank, the oil pressure it admitted to the main
bushing behind the flywheel, where it feeds the x drilled crank, rod big end and the other end of the crank
main bushing in the gear case.

there is also a variant known as a "roller" version, which has a ball brg at the flywheel end and a bushing at
the gear case end where the oil is admitted to the crank shaft x drilled to feed the rod.

i think as long as the engine keeps the little red indicator showing the engine will have enough oil pressure
to run at the intended speed.

bob g

[BruceM]

Thanks for the info, Veggie.  Another low speed option is a wonderful contribution.

[oliver90owner]

That does not leave very much belt contact on the small sheave.

Much less power to transmit as well, so no particular bother?

Regards, RAB

[rcavictim]

I'm just looking at the factory supplied manual for my  Changfa ZS1115G engine.  It has ball bearings at each end of the crankshaft.  Large one at flywheel end is a 314, GB276-82.  At the timing gear end is a NJ312, GB283-87.

[flywheel]

I'm just looking at the factory supplied manual for my  Changfa ZS1115G engine.  It has ball bearings at each end of the crankshaft.  Large one at flywheel end is a 314, GB276-82.  At the timing gear end is a NJ312, GB283-87.

The "G" in ZS1115G means double bearings, I believe the 314 is a ball type and the NJ312 is a roller type bearing.
                                                                                                                                           flywheel

[rcavictim]

I'm just looking at the factory supplied manual for my  Changfa ZS1115G engine.  It has ball bearings at each end of the crankshaft.  Large one at flywheel end is a 314, GB276-82.  At the timing gear end is a NJ312, GB283-87.

The "G" in ZS1115G means double bearings, I believe the 314 is a ball type and the NJ312 is a roller type bearing.
                                                                                                                                           flywheel

How do you know all this stuff?   

[mobile_bob]

Flywheel is the only guy i know with more chinese diesel engine's that i have!

thats how he knows this stuff



his picture hangs next to chairman mao in chinese engine factories, i am told

lol

bob g

[flywheel]

I'm just looking at the factory supplied manual for my  Changfa ZS1115G engine.  It has ball bearings at each end of the crankshaft.  Large one at flywheel end is a 314, GB276-82.  At the timing gear end is a NJ312, GB283-87.

The "G" in ZS1115G means double bearings, I believe the 314 is a ball type and the NJ312 is a roller type bearing.
                                                                                                                                           flywheel

                                                               

How do you know all this stuff?   

Amazing what you can find out with a computer!  I get my hands dirty sometimes also.
                                                                                                                           flywheel                                                                 

[flywheel]

Flywheel is the only guy i know with more chinese diesel engine's that i have!

thats how he knows this stuff



his picture hangs next to chairman mao in chinese engine factories, i am told

lol

bob g

No thats not quite right Bob - I remember the scout motto, Always be prepared!
                                                                                                              flywheel

[veggie]

After running the 195 under load for while today, I dropped the speed down 450 rpm to see how she performed.
The engine is now running on a WVO blend and seems to be quite happy with it. (no more stink  )
At 450 rpm, the engine is super quiet with virtually no vibration. FUN! 

Although my roid is getting a bit jealous. 450 rpm surely puts the Changfa in the "slow speed engine" class.

veggie

[Apogee]

Sorry Veg,

But as cool as this is (and it's VERY cool), painting it 'roid green is going a bit too far imho...

As hard as you try, it can turn like a duck, quack like a duck, sip like a duck, and even LOOK like a duck... but alas, it's NOT a duck....  LOL!

Where did the heavier flywheel come from?

Nice job!

Steve

[veggie]

Sorry Veg,

But as cool as this is (and it's VERY cool), painting it 'roid green is going a bit too far imho...

As hard as you try, it can turn like a duck, quack like a duck, sip like a duck, and even LOOK like a duck... but alas, it's NOT a duck....

Where did the heavier flywheel come from?

Nice job!

Steve

Thanks Steve,

That's not roid green.....it's John Deer green.!!
The heavy flywheel was custom fabricated for the "Slow speed Changfa" project.
http://www.microcogen.info/index.php?topic=477.0

cheers,
veggie

[Apogee]

Very cool!

Any idea of the output @ 450 and 600 rpm?

And btw, the green does look very nice even if it is blasphemy....

:-)

[veggie]

Apogee,

Sorry, no idea of the BHP output @ 600rpm. The speeds are all wrong on the gen head for me to test at that speed.
The engine normally runs at 900 rpm and can generate 3kw of electrical output.
Based on the 2:1 rule of thumb, that would put the engine at 6HP@900rpm.
My wild guess is that 600 rpm would net about 3HP, and 450 rpm might be about 1.5hp.

veggie