Lister Engine Forum

Slow Speed Diesel Engines => Changfa Engines => Topic started by: dkmc on October 27, 2021, 11:13:01 PM

Title: Chang-chai and ST head, deal? Or no deal?
Post by: dkmc on October 27, 2021, 11:13:01 PM

It ain't pretty...
Found this, seller was asking $600 said he'd take $550. I saw it run, started right up with the electric starter.
He knows nothing about the ST head, wires are disconnected. Data tag is unreadable except for 2000 which may
be the year built. Is there a stamped model/ serial number someplace?

Worth the money?
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: guest18 on October 28, 2021, 12:46:34 AM
It looks like an ST-7.5 head. It looks like itís been outdoors for some time. It will probably need new bearings and brushes. I would see if the generator head works.

If itís been rained and snowed on the generator head probably needs to be rewound. Thatís if the rotor and stator laminates are still good.
Might be cheaper to purchase a replacement ST head.

I think $550.00 is too much of an asking price. It seems like it was not taken care of very well.


I believe your in the North East. Check for freeze cracks in the block around the cylinder.
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: dkmc on October 28, 2021, 01:31:17 AM

Also meant to ask, is there a manual available online for these engines?
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: mobile_bob on October 28, 2021, 03:27:25 AM
i wouldn't give any value for the st head, it is an st8 which is really an st7.5
if it works or can be made to work economically then it is a bonus, but don't add value for it in the purchase price.

the frame and pulley maybe 50 bucks

the engine? hmmmm, given the current market and there really aren't any available
for sale, at least yet, that value is between the buyer and seller.

if it were me and i really was in need of the unit, i would offer no more than 500 cash money, "if" the engine started up from cold, and not after having been running before you got there.

if it started from cold, i would maybe go 500 for the unit, if it was warm when you got there you really have no idea what he had to do to get it running. he may have needed to give it a half can of ether to get it going.

a hard starting engine is going to need work, and that takes the value down to maybe about half his asking or around 250 bucks.

as for a manual, i am not sure about an online manual, but i think i have one i can copy and send you, just would take a bit to find it.  i have several, just finding one is all we need.

bob g
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: mobile_bob on October 28, 2021, 03:42:01 AM
+1 for hwew' comment about checking for freeze cracks, fill it with water and check for leaks, cracks etc.

i am also concerned about the condition of the aircleaner in the picture, why is it all apart? how long has it been open?  has it been stored under cover? looks like it has been fending for itself out in the elements, and if the aircleaner has been left open? dirt? water, bugs, leaves, did i say dirt and water?

if the intake valve was closed then the cylinder was probably saved, but how much rust on the valve stem, and when he rolled it over, how much dirt and crap was ingested on the first startup.

the more i look at it, and the apparent poor condition from the elements, someone really didn't care much for this generator, and a dead generator really isn't a generator is it?

500 bucks is a gamble that i wouldn't take, not unless i was prepared to spend the time, and money to go through and overhaul the engine, and maybe also replace the generator head, and even then the frame is a light duty portable designed for intermittent use.  probably just what this poor thing did,  run for several hours of power outage, then left to fend for itself, wash/rinse/repeat until one day it either didn't want to start (probably when the aircleaner was taken apart) or the generator quit (probably when the control box was disassembled.  then they just went for a beer and a trip to town to buy a cheap gas generator and this thing was left where it sat.

i bet i am more right than wrong on this one, and the more i think about it, 250 bucks is a good cash offer.

he ain't gonna get more from anyone else!  there aren't that many of us out their looking for these things, and even fewer than are looking that have the ability to make it work again. 

offer him 250 cash, leave your number and walk away, tell him you have to go look at another one that has been kept under cover and works.

he will either stop you and take the offer, or he will be calling you shortly.

btw, take you wife with you, start with small talk, ask if he has a wife, get her involved!

to most wives that rusty pos?  hell ya babe we are gonna take his 250 bucks!

:)
bob g
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: guest18 on October 28, 2021, 04:05:47 AM
Oh, while checking for freeze cracks on the outside when filled with water, itís also good to check the oil in the crankcase for water.
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: guest18 on October 28, 2021, 04:58:24 AM

Also meant to ask, is there a manual available online for these engines?

What engine engine model is it?

S-195, S-1100, Ö?

Here is a Changfa S-195 manual on line.
http://dinatek.ec/wp-content/uploads/pdf/manual/MC1-Manual-Operacion-Changfa-1100-195.pdf
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: guest18 on October 28, 2021, 01:55:12 PM
Another thought, Masters Farm Supply based in Florida bought out all of Hardy Diesels parts stock of the Changfa / Chang-Chai type engines. They might be able to help you with a manual, and parts.

https://www.microcogen.info/index.php?topic=3355.0
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: dkmc on October 28, 2021, 02:16:00 PM

Thanks, I'll check that out. The PDF you linked is generally helpful enough. The engine seems to run fine as demonstrated by the seller. As far as $250 goes, if someone can actually buy something similar to this for that price, I hope they post their score on this forum, it will be a treat to see.


Another thought, Masters Farm Supply based in Florida bought out all of Hardy Diesels parts stock of the Changfa / Chang-Chai type engines. They might be able to help you with a manual, and parts.

https://www.microcogen.info/index.php?topic=3355.0
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: guest18 on October 28, 2021, 02:44:06 PM
They can be found, when I do find them I post them on microcogen.

Here is where stuff is posted:
https://www.microcogen.info/index.php?board=66.0

I do periodically go in and remove items that have been sold or that are no longer available.
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: dkmc on October 28, 2021, 02:54:13 PM

Yes, I am a member. I see parts listed for sale, no running engines with questionable generators on a trailer for $250. Have there been such things on the list before?  I'm just curious.

They can be found, when I do find them I post them on microcogen.

Here is where stuff is posted:
https://www.microcogen.info/index.php?board=66.0

I do periodically go in and remove items that have been sold or that are no longer available.
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: guest18 on October 28, 2021, 03:05:41 PM
Yes,
When I find them, I post them.

It takes a fair amount of effort to keep the Hardware for sale by NON members up to date.  Iíve been busy and lately I have not had much time to search the web for items. Iím working on getting back to do some more searching. But, not in the capacity I once was.

 Members, including myself, post items there so members have first shot at the items. Once members are logged in the section only becomes visible. This section has been made because the items posted in the original for sale section weíre getting picked up by non-members. Members that could of used the item were not given a chance to purchase the posted items because non members were beating the members to the sale. We decided to do something to fix it so only members can see the items. In turn, quite a few members were able to pick up great deals that would of normally been picked dry by others. What brought this into fruition was the time Surplus Center was selling new half liter, twin cylinder, Cat/Perkins dieselís for I think it was $599.00. That was a sale of a lifetime. And by creating the Hardware for sale by NON members it helped a few members that were interested in them to purchase one.

Now days with all the search engines on the internet the Hardware for sale by NON members is less effective. But, every bit helps.
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: mobile_bob on October 29, 2021, 09:51:33 PM
dkmc

upon rereading this thread, it appears to me, that possibly you already had the thing bought and hauled home before you posted the questions??

after rereading and looking at the "big" picture i see the unit strapped down to a trailer, which leads me to think maybe it was either ready to come home with you, or already arrived?

had we known that fact, we might have responded in a much different way.

i for one posted what i said based on trying to help you as a prospective buyer go into it with open eyes. and also get you the best deal possible.

so now that you have it, maybe we can help you get it sorted out and doing what it is you want it to do.

bob g
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: dkmc on November 07, 2021, 02:03:38 AM
Finally earlier this week, the seller got it off his trailer, and called so I could pick it up.
And today, 5 days later I got to tinker a bit and generate more questions.

There are some things that make me suspicious the engine has not been used much. The oil was a butterscotch color and the sump filled to the 'add' mark. Does this sound like the way they come when new? Not a spec of dirt in the fuel filter housing. After I changed the oil and worked the air out of the fuel system I managed to get it to run. It runs nice, and restarts nice now that the air is purged. Added some 50/50 mix to the hopper and no sign of cracks or coolant leaking or getting into the crankcase so I guess there's no freeze damage. PS the oil drain plug was finger tight.

Questions:
As I said the data tag is worn away and unreadable, but....On a small decal near the fuel cap, are these numbers
XK06-105  1220.  A serial number perhaps? Or model number?

Also, I've attached a pic, what is the function of these 2 doo-dads? One on left has a spring under the threaded cap, and a 2 screw mount flange. One on the right has a nut that seems to turn but not round & round and just one screw to hold it to the engine.  I don't have a manual for this engine, it's for a similar one. Not very informative.
TIA

Tomorrow, the ST head. Perhaps I can measure the brush length, and if someone can tell me the length of new brushes, we might all get an idea as to the hours of run time this setup has endured.

Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: mobile_bob on November 07, 2021, 02:57:55 AM
i am not sure about those two things in the picture, but my guess is they are a fuel stop setting and a fulcrum setting for the governor, actually they likely both work with the governor.   as such i would "not" mess with either of them.

especially without knowing more about them, and having a manual in hand for the engine.

sounds like you got a good runner! 

now the brushes,  again i don't know the length they were as new
but st heads are famous for one brush wearing faster than the other, same for the slip rings... so if both brush sets are about the same length, and the slip rings look about the same it is likely the thing doesn't have a lot of runtime hours on it.

and i wouldn't change the brushes unless they are running short enough to look like the springs are close to limit or contact the slip rings.

do you know if it was stored under cover?  if so that would be a plus.

i would clean up the slip rings and see if you can get it to generate some power, maybe a 100 watt light bulb to start with.

if you can get it to make power, and you see signs of water ingress, don't run it for long or power much of a load.  i would then take it all apart, have the stator and rotor tested for shorts, and if they test ok, maybe have them baked dry, vacuum dipped and baked to set the varnish.  a good motor shop could advise you on that.

you just want to make sure that the thing is clean, dry, and has enough varnish to set the windings, and protect or insulate as well as you can.  if you take it all apart and take the stator and rotor in for testing and bake/dip/bake... it shouldn't cost too much, the motor guy could tell you if it would be worth doing or not.

then either replace or repack the brgs and reassemble, i would replace the brgs, but that is up to you.

it might have a failed rectifier, which is not uncommon, and easily upgraded for not much money.

it is really so hard to diagnose or advise from pictures, pictures can make things either look dramatically better or worse that what they really are in person.

my bet is the old girl doesn't have a lot of hours on the unit, and it might well be the rectifier gave up and that is why the generator box was apart and the thing sat around unused up till you became the proud new papa and brought it home.

i am not sure if the engine is a s195 or an s1100, the s1100 being a bit bigger of course.

if you have an 1100, you did well, i wish i had scored one preban,  iirc the 1100's were direct injected and used a ball brg on the flywheel side of the crankshaft to carry the load,  common for an 1100, less common on the 195's

sounds like you got the start of a good project.
and in my opinion once you go changfa type your hooked for life.

(me) "my name is bob, and i am a changfa addict"

(group) "hi bob!"

:)

bob g
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: dkmc on November 07, 2021, 11:55:17 PM

Another curious observation while inspecting the ST head....

Wire lugs on the output terminals with no wires crimped to them.
Are they from the factory? Could it be this generator was never used?
The jumper 'buss bar' that connects the output for 120-240 or just 120 was on the F2R terminal, not connected to anything else. Why I have no idea. I could not figure out how to remove the brushes, but checked and observed continuity between the slip rings and brush terminals. Maybe it needs to be flashed? I need to determine which wire is the + on the rectifier. It started right up from 50F today on the first spin up.

Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: guest18 on November 08, 2021, 01:03:23 AM
This wiring diagram should work.

https://www.utterpower.com/wp-content/uploads/2010/07/Figure1.gif
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: dkmc on November 08, 2021, 02:13:01 AM

+ to the slip ring closest to the windings..........got it.
Thanks.

This wiring diagram should work.

https://www.utterpower.com/wp-content/uploads/2010/07/Figure1.gif
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: veggie on November 08, 2021, 06:38:31 PM

The spare brushes that came with my ST-5 are exactly 1 Inch long.

Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: mobile_bob on November 08, 2021, 07:28:43 PM
that seems odd to have uncrimped eyelet connectors still in place, that would make one believe that it may never have been used.

can you get a closeup of the slip rings?

it is very common to have one of the two showing more wear than the other, that is if it has a bunch of hours on it, if it shows equal and little to no wear, and the brushes are as veggie states about an inch long... it may well be that the unit as a whole was either never used or used very little, and just left in a wet/damp environment making it look worse than it really is.

you may have found a diamond in the rough?

have you looked down in the hopper to see the cylinder liner?  is there a bunch of flaky rust and lime buildup?  i would expect a nice coating of rust, so that would not indicate much but it it is free of flaky scale lime buildup that along with the oil looking so clean would lead one to believe that this thing may never have been put into service.

might be it sat around for a long time new, and someone pulled the box top off, didn't know how to connect a load to it and simply walked away leaving it in an unprotected area.

again, can you talk a picture of the slip rings?

bob g
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: dkmc on November 09, 2021, 12:08:45 AM
Revolting developments and a sign from.......someplace?

Yesterday I ran the engine a bit as I said, and it started much easier. Run time maybe 10 minutes total.
I noticed a drip from under the oil pan the day before, and now again after just a bit of temp build up, it's dripping slowly again. Luckily, I'm able to pick it up high with the forklift and check the underside. I suspected the seal on the drain plug, so took it off. The rubber O ring (such as it is) was mashed flat and cracked. I installed a new one, and snugged the drain plug. Re-installed the oil.  More dripping.......!  So once again, I hoisted it up and got underneath for a really up close look. It was then I noticed the dent on the corner of the oil pan. And separately, nothing to do with the dent, I discovered a tiny crack in the pan under the drain plug. Crap!  But.....it gets better!

I drained the oil again last night. And I spent a lot of time thinking (when I should have been sleeping) about an approach to the problem. I did consider JB weld, but I wouldn't feel right about that. Today I picked it up from the handle above so no  forks interfering below. And I see the pan is not obstructed by the frame work. So I removed the pan bolts......

And here is where the horror show begins. But with a silver lining!
I half expected to see some.....SOME...... sludge in the pan, but nothing like this!  Not only was there about 1" of sludge, there was also a generous heaping helping of Foundry Sand. And the pick up screen was in-bedded in it and it seems about completely plugged. I have no idea how the oil pressure indicator was showing pressure.
It's hard for me to believe with this amount of sand, that this was anything other than deliberate. And this is a Changfa not a Listeroid.
As you can see from the pics, I was very relieved to see the important parts undamaged from sand and lack of oil. Somehow, it seems the tiny crack and annoying oil leak was a blatant cry (cry, dripping oil, crying tears, pun intended)  from the engine to implore me to remove the pan and rescue it from certain death.


Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: dkmc on November 09, 2021, 12:14:52 AM

More horror........

The goo on the cookie sheet shows the amount of sand chunks on the right side.
Beefy chunks in gravy is what I actually said out loud when I scraped it out of the oil pan.
This explains the butter scotch oil that came out initially.



Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: mike90045 on November 09, 2021, 12:17:53 AM
Speechless  !!
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: dkmc on November 09, 2021, 12:25:48 AM
Now for the good news.  I don't think the slip rings will need to be investigated after you see these pics Bob.
Super lucky the sand apparently didn't make it into the oil passages and thru the bearings.....yet.
I am so glad I took the pan off! A bit of silver solder will repair the crack.

I don't know what the cam lobes and rod inserts might look like with 'hours' run time on them, but these don't seem to have much time at all.

Some rust in the cylinder below the ring travel........

Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: mobile_bob on November 09, 2021, 12:34:57 AM
all i can say is wow!

that looks to me like sabotage by someone, maybe at the factory level, maybe someone after delivery?

maybe a previous neighbor that got tired of listening to the thing running outside his bedroom window?

this reminds me of a short story

i was 15yo, working pumping gas at a station on the edge of town,  i worked till closing at 10:30pm a few night a week.  in the winter months it got slow after about 8pm so i had time to do my homework while sitting at the counter.

just to my left side through an open doorway, was the aircompressor, and that damn thing was so noisey, not the common aircompressor noise but banging, squalling, raising hell sort of thing

every night in an effort to quiet the beast i would check the oil and find the dipstick covered in metal flakes and no oil at all.  so i would buy a can of "glitz" generic stp stuff that was about 200weight, thick stringy nasty, came in quarts, was cheap and the compressor would quiet down so i could live beside it.

this went on for months, then one day my boss having spotted the half quart of glitz sitting beside the beast asked me "bob, are you the one oiling my compressor?"

me:"of course, i am tired of listening to this thing pound"

boss: "how the hell do you think corporate will replace it if you keep oiling it?"

he was moderately serious!

so i quit oiling it, and it kept pounding for a few more months.

then one day they came in with a portable office, tore down the old station, took away the vending machines, and our beloved compressor.

they built a new station, and just about the time they were done the truck came back and unloaded a bunch of new looking vending machines, and...  wait for it,,,

the beast returned!  shit!

they hooked it up, i told them about our problem with it, me oiling it, and my boss having a fit,  and they told me "hey kid, its not my job"  basically get out of my way and let me get back to hooking this thing back up.

they got it installed, and fired it up... and what do you know, they overhauled the beast
and it ran quiet!  never heard it run that quiet ever...

your oil pan, and crap found within reminded me of what the mechanic must have thought when he tore into the beast and was faced with a ton of metal flake and sticky glitz oil treatment.

i am thinking he was having similar thoughts that you had when you dropped the pan on your engine.

like   "wtf" 

bob g
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: dkmc on November 09, 2021, 12:50:31 AM
Great story Bob!  I do admit my heart sank when I saw the contents of the oil pan. Sorta looked like bad meatloaf night.
I could only imagine the rest of the engine was TOAST.  And I'm not in any way familiar with Changfa's so the nearly-metallic whack when it fires had me thinking it was perhaps an actual rod knock instead of typical fuel knock. By no means a 'silent' generator. More like crude, rude, and obnoxious. I kinda like it...
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: mobile_bob on November 09, 2021, 02:19:39 AM
they make a sharp "bang", "bang", "bang" as they are spooling up and then once they settle down to a steady rpm they still have a sharp diesel knock.

its hard for me to imagine that crap being in their from the factory, they do a pretty good job of cleaning the interior castings, and they also paint pretty well too... a tiny bit of sand maybe, but what you have?

somebody either was having a bad day, or didn't like that engine, or its owner.... or maybe all three?

you may want to pull the oil pump and check it for scoring or damage?  iirc the pickup screen is pretty fine and should sort out the bigger stuff just fine, but the really fine stuff? 

i am thinking that you would have seen some crap in the rod brg if it got into the oil pump.

also look at the crankshaft, there is a plug(s) that allow you to clean out the rifling/drilled passages within the crank... you might want to pull them and run a wire up and see if anything got into there?  my manual refers to those passages as being part of the maintenance of the engine, so maybe the design traps grit in the crank rifling/drilling so it can't make it to the brgs?  there must be some reason that the manual refers to removing and cleaning out those passages in the crank... i never gave it a lot of thought until this came up.

it might be that the centrifugal force of the spinning crank might force the grit into the pocket behind the plug in the crank, and in doing so keep it from going directly to the rod brg.  i think it is possible?

look carefully around the cheeks of the crankshaft near the rod journal, i think you will find at least one such plug, maybe one on each side? i just don't remember.

fwiw

bob g
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: veggie on November 09, 2021, 09:18:40 PM

WOW !!  :o

Lucky that you stripped it down.
After a good cleanup and re-assembly it should be a good runner.
As mobileBob noted, parts are available easily for these engines.
AliExpress has lots of parts at good prices.


Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: guest18 on November 09, 2021, 11:23:06 PM
Yes you were lucky.
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: dkmc on November 10, 2021, 02:03:45 AM

Never ordered from Aliexpress, skeptical. I've seen some things on there of interest, (more of a wholesale industrial nature) but when I've sent an inquiry I've never heard anything back.



WOW !!  :o

Lucky that you stripped it down.
After a good cleanup and re-assembly it should be a good runner.
As mobileBob noted, parts are available easily for these engines.
AliExpress has lots of parts at good prices.
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: dkmc on November 22, 2021, 05:57:44 PM
Progress on the sand pit....

I added a piece of stainless perf. metal behind the fine screen in the pickup to prevent it from being sucked in and distorted like I found it.
I hammered the dent out of the oil pan and that made the crack around the drain bung more pronounced. I think now that the dent did contribute to the crack developing.
It's really clear to see after bead blasting, I think there was braze flux plugging the hole "from the factory".
 I thought of checking the pick up position while it was apart and I'm glad I did because the pick up was slammed flat on the very bottom of the pan. I had to do some heating and bending but now it's about 5/8" up off the bottom.

Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: dkmc on November 22, 2021, 06:10:31 PM
I added a generous amount of silver solder around the bung to strengthen that area. A coat of paint, and it's looking much better. It runs well and starts up easily now, I think the lucas treatment and ATF I put in the fuel helped a lot. Took the ST head partly apart and ordered new bearings and brushes as the bearings are growly and the brushes are stuck in their holders. I'll probably have to bash them out.

A short video...
https://www.youtube.com/watch?v=rOgIELxKVUo

 
Title: Re: Chang-chai and ST head, deal? Or no deal?
Post by: veggie on November 23, 2021, 02:47:47 PM

Runs very good !
Nice work.

Suggestion: an open air intake pointed upward is a dangerous arrangement for the engine.
I assume it's just temporary but be careful. Stuff a rag in it when not running.
A tiny piece of debris can mess things up  :)

My Changfa 195 leaked oil at the drain plug welds also. I had to remove it and get it brazed the same as you.

veggie