the DEV RANDOM

[cadillackid]

sounds like the scholastic style webasto works like an oil fired boiler. with a high pressure pump and a Nozzle blowing fuel into 2 spark electrodes that make sure it lights off..

[cadillackid]

OK so here we go.. of course the chinese manufacturer wont tell me their communications language.. so really i just have to Geek it up and figure it out my damn self...



I figured my main interest is in controlling the heater remotely so I want to read what the control device sends to the heater and see if I can re-create the records..


while the chinese are known for making really cool devices, they REALLY tend to stick to old-school USA communications protocols and electronics conventions..



my heater has 4 wires in the control harness. its easy to guess that 2 will be power and ground, in some the 3rd wire will be a On / Off. meaning when it has 12 volts the heater turns on, when it has 0 the heater turns off... and then 1 wire would be communications..



in the case of this heater it turns out there are 2 communications lines.. a send and a receive.. one wire sends data from the control to the heater and the other sends data from the heaster to the controller.



Red - +12
Brown/green - Ground
Blue - TX from control
Green - TX from heater.



when I stuck a meter on blue or green to ground I saw a basically +5 volt signals that fluctuated slightly I surmised that these were communications wires.



+5 volts is perfect for a nice Logic analyzer.. holding at positive voltage indicated typical TTL level communications from a micro controller . ther wire is held high by a pullup resistor and then each bit is produce by bring the wire down to 0 for a specified time then raising it back up.. this produces 1s and 0s. in the waveform.





when I looked at the timings it seemed to me to be standard single wire serial data.. I figured I should be able to make something out of it if I were to run an analyzer across it.. my Saleae logic analyzer has protocol recognition.. so I told it to go to it. and it came back with 8 data bits, 9600 baud serial data..



after I took a few samples I realized that a record was easy to read humanly at least to get its numbers..

                         
  S T 2 0 0 0 3 0 0 0 0 2 2 0 2 9 0 0 0 0 4 7 2 0 6 O V

starts with an ST and is 'over' with an OV

watching the heater side it starts with an ST1

so right out of the box you can say the heater is address '1' and the controller is address '2'

so I captured more records and I set the heater from 71c to 75c. and I could see a change in the record.

see the 75 in there? yep one can assume thats the field where the temperature belongs.

S T 2 0 0 0 8 7 5 6 0 2 2 0 2 9 0 0 0 0 6 0 4 0 3 O V

the last 5 digits always change with any change in the other data.. so its assumed that this would be an error checking mechanism.
serial data like this is very prone to errors.. sometimes you add up the ASCII or hex values of all the prior digits and it would be a checksum
so i did that and no-dice didnt get 60403. then i thought well the largest 16 bit number in the universe is 65535 which just happens to be 5 digits long
and ive never seen anything larger in that field no matter how much data I captured.
that was a tip-off that they may be using a CRC method.. so I took all of the digits after the 'ST' and before that 60403, cheated and ran them through an online CRC calculator
200087560220290000
and it came back with a hex number of EBF3 when i ran it through a CRC-CCITT seeded with 0xFFFF.. oh I got a hit!! when i converted it to Decimal i got.. you guessed it 60403.

so now im well on my way to cracking the chinese code for the heater control.. this will be rather easy to control with an arduino or raspberry pi device.



Dark Green - Start sequence
Light Green - unit Address
Light Blue - Temperature setpoint
yellow - 16 bit CRC-CCITT seeded with 0xFFFF
red - End Sequence..

and thats how I geek out with espresso when i get bored..
-Christopher

[johnbloem1974]

That's some badass sleuthing and code-cracking right there!!

John

[Booyah45828]

Looks like you cracked the controller to heater comms. Now to crack the heater to slow the initial warm up down.

[joeblack5]

Nice job, that sure gives you a boost when you can figure it out..great fun.. I hate proprietary stuff and it is nice to break it down..

Johan

[cadillackid]

Originally Posted by joeblack5

Nice job, that sure gives you a boost when you can figure it out..great fun.. I hate proprietary stuff and it is nice to break it down..

Johan

Break it down and share it


booyah - this isnt the VVKB heater but this will helpo with the startup as the heater to control comms show me the VA the glowplug is using, the RPM of the inducer motor, the exhaust temp, water temp, Hz of the fuel, mode and couple other things I havent figured out yet..



idea being that if i choose to drive the fuel pump myself I can see what the controller wouldve been sending, the temperature to know if i have a flame, inducer drive.. whether the glowplug is on or not..



im thinking ill put a glowplug in the air intake to warm the air when i see the heater's glowplug is on...


there may be other things i can do wit hthe controller so of course as I learn ill just "happen to send" various data at the heater to see how it responds.. there may be modes I can toss at it that are not in the realm of the button presses on the keypad..

[Diverdude0075]

Originally Posted by cadillackid

I have the full chart and how to calculate the speedo if yours is off we can probably get you fixed up pretty easily if they kept the IHC dash cluster
-Christopher

Hi Chris,
Would you mind helping me out with calibrating my Speedo? Now that my upgraded A2000 is out of limp mode, the speedometer is working! It’s really off though. I think at 53 mph on the bus gauge I’m actually doing around 60. Makes sense since I now have overdrive.
Thanks,
Josh

[cadillackid]

on the electronic engines the speedometer is handled by programming the ECM.. I was thinking you kept your original ECM? or did you swap ECM's with the new trans?

[Diverdude0075]

I swapped to the donor ecm. At first the seller didn’t want to part with it, but he finally let it go so I put it in.

[cadillackid]

so you will need to program it for your bus rear end, the 0.74 final drive and the number of pulses per mile for the speed sensor (16 pulses per rev of the driveshaft). if you saved an engine file with servicemaxx prior to moving ECMs you can read the data from the file to put in the computer. otherwise you calculate it


lay a tape on the ground.. and write a chalk mark on a rear tire vertical in the sidewall. the tape 0'" shoul;d be at the mark and the tape layed out along the bus.. drive forward exactly 1 tire rev (without running over the tape). measure the inches travelled on the tape. there are 63360 inches in a mile.. so say you drove 120 inches for 1 tire rev. divide that into 63360. == 528. you have 528 tire revs per mile.



now driveshaft revs.. if your bus has a 4.78 gear.. multiply that 528 x 4.78 == about 2523.84 driveshaft revs per mile. now get 16 pulses of the sensor per driveshaft rev so multiply 2523.84 X 16 == 40381


so in my example in the computer you would program the parameters with the free version of service Maxx.



1. rear Gear ratio = 4.78
2. tire revs per mile = 528
3. pulses per driveshaft rev = 16 (standard for allisons)
4. final drive ratio = 0.74
5. Pulses per mile = 40381


that should get your Speedo working correctly..



again I cant get screenshots for you as my Redbyrd is torn apart and its electrical system disconnected so i cant run the computer on it right now. in a few days when its back together I can.

[Diverdude0075]

Thanks Chris! My rear ended is 4.78! I’ll check the measurements. I still have the old ecm too just in case. Will service maxx work with the six pin connector, j1708? I haven’t converted to the j1939 yet.

[cadillackid]

yeppers.. service max using a nexiq or clone works with the 6 pin just fine.. (allison DOC needs the 9)..

[cadillackid]

It seemed like the Dev is slower than it should be in fact it’s been that way for awhile. I relocated the exhaust tail a few months ago as ever since I’ve had the id sometimes get whiffs of exhaust inside, esp if the driver window was open putting a negative pressure on the bus. Never enough to register on a CO detector but annoying nonetheless. I attributed it to air leakage into the back so I moved the pipe to the left side behind the tire. Similar to the way new busses are done. It seemed a little better but def did not solve it.. so I turned the “smoke wheel” up on my Bosch pump which really just makes it smoke pretty heavy on the low end.

Stabbing the brake hard with the bus parked and then Hitting the throttle pretty spry resulted in being able to repeat the inside smell.. and of course quite a bit of smoke. What I didn’t expect was to see the smoke coming from under the hood.. quite a bit of it..

Inspecting things revealed that this is all that’s left of my exhaust manifold gasket.


I didn’t yank or pry on the gasket. That’s how it came out. So now I know why she is a tad on the slow side.. the new gasket is below for reference.

[Bert06840]

Someone put a Volvo 5-cylinder gasket where it didn't belong.

Just kidding.

How did it end up that way? Overtightened?

[magnakansas]

so, are you going to take the manifold out of the engine bay and check to see if it flat enough to go back on the head?

Or

Do you already know how flat the manifold is?


william

[cadillackid]

I did a poor mans version of flatness which was dropping a straight-edge across it and then rocking it or insert a feeler gauge in the gaps. , its not Perfectly flat but its also not like .050" out either.. from what I can tell its all under .020" in variance. I realize thats not near as good as pulling it and sending it to a machine shop to have it surfaced..



the main issue I need to solve is the fac t the damn bolts keep backing out.. nev er have I had a stock manifold want to backl its bolts out like this seems to want to.. and apparently others with 360s have had the same issue.. so now the piece of the puzzle to solve is whether the original gaslket was correct and which way it goes in. I was going to buy my Gasket from my Local IH parts counter however it was backordered with no ETA so i had to go to the interwebs.. my IH service book makes no mention of front / back, nor does the IH service book I have.. whats even more interesting is the IH book doesnt have a torqueing order for it either.. just a spec of 60 ft lbs.



the method I have used to torque these in the past has been to work from the center out toward the ends.. similar to how you would torque a head. of course the center bolts are tough to get a torque wrench on.. ironically those are the ones that stay tight.. the end ones are the ones easiest to torque correctly but also back out the most.



according to IH the metal gasket is re-usable so ive never felt bad about loosening out and retorqueing the bolts when ive had some get loose..


there is another type of gasket available however im told it was only ever used for AG applications.. (the DT360 was a tractor engine Long before it was put into trucks and busses).. I bought a set of that type gasket as well however it doesnt look like it would fit as well so im using the OEM style.



my engine was replaced with a reman in 2004. the engine itself is a Jasper so I have no idea what shop installed it in the bus, it couldve been the schools themselves or couldve been a reputable diesel shop, theres no service records so I have no way of knowing if the correct parts or procedures were followed.. and honestly the IH service book literally just says "install exhaust manifold with gasket and torque to specification".. thats it..



I had last checked these bolts in spring 2020.. well with covid and all this bus has had a *LOT* of use.. I ran it alot of miles in the last 18 months.. maybe I just need to add manifold torqueing to the list of things I do when i change the oil..



on the PLUS side this will be the easiest oil change ever as i dont have to snake the oil filters full of oil around the S-shaped down pipe sincei its Off right now


-Christopher

[Bert06840]

Originally Posted by cadillackid

...
so now im well on my way to cracking the chinese code for the heater control.. this will be rather easy to control with an arduino or raspberry pi device.

Attachment 55363

Dark Green - Start sequence
Light Green - unit Address
Light Blue - Temperature setpoint
yellow - 16 bit CRC-CCITT seeded with 0xFFFF
red - End Sequence..
...

Woow... I just literally accidentally ran into this...

It's time to order my dedicated hydronic heater, it'll be snowing soon.

Is this the D&E heater or the VVKB?

I tried to find a place that sells the D&E but I can't - could you give me a pointer? Thanks much in advance!

I found this company on Amazon https://www.auto-parkingheater.com/car-heater/ , hopefully they'll tell me soon how much their heaters cost.

bert

[Bert06840]

Christopher, take a look at https://www.skoolie.net/forums/f6/gi...tml#post450468 you may be interested in what one of the chinese diesel heater companies sent me.

[cadillackid]

Originally Posted by Bert06840

Christopher, take a look at https://www.skoolie.net/forums/f6/gi...tml#post450468 you may be interested in what one of the chinese diesel heater companies sent me.

this is great! esp the pictures.. whats interesting is the 9kw unit they have listed appears to be identical to my VVKB heater..


the one beef i have with these chinese Coolant heaters vs the real webasto is the fact neither of mine nor a buddy's (ill have to find out the brand) do any type of throttling.. they kick On full blast, heat the water to temperature then shut off.. the pump of course stays powered the whole time..



the real webasto in my red bus turns on and ramps itself up and down to maintain.. and will shut off at some point.. I dont have a thermometer on the coolant lines in that bus to see but seems to be around 170-175f.. I like the fact it throttles..


none of the chinese that I ask have a clue it seems when it comes to whether their heaters throttle or not .. the real webasto do and the eberspacher claims to..

[magnakansas]

What about some sort of lock tabs like stage 8 ? Also, Ford uses these funky bolts that are triangular… the tips of the triangle are interference fit, I think. Bet arp or stage 8 has an off the shelf fix. Then there is always safety wire, but is always a pain ….

William