Tom, if you are reheating the gas, put more of the tube on the manifold to heat the gas to go to the filter. But have the filter up front. Filter it in the engine compartment then into the TB. Or have the filter box infront of the radiator or some where it can be serviced and changed out. Have a hot filter in back and paper filter up front. Just a thought. I’m new to this paper filtering but I can see the advantages if you can make it work. I’m still working on my hot filter. Wiill show it off when I get it done.
Bob
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Thanks for the drawing Tom, now I understand what you are saying. Bob
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Andy, go to Craigslist then to some place likeMemphis and look under cars and trucks. I’m sure you could find a good truck BUT they are not cheap. You may even think they are expensive TomC
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Hello woodgasers; You know I have been having quite a discussion on cleaning up the gas for my engine. Seeings Max is our resident expert on Imbert style gasifiers and accessories, I have gone to two of his threads to learn. One on the Audi and the other on a Nesson Micra (?).
The following is a portion of his post;
On the Audi the gastube has to make a bend over the open trunk lid and in the summer go parallel with the 1,1m long “dishtable basin” (?) to its front “gabel” (?) in order to get enough cooling to dew point. In winter, it is led in to the basin from the back “gable.” (?)
So, this is a wet system with two matress pieces of open cell matresses
superposed on each other with ss net under and above, to form “manifolds” to spread and collect the wet gas.
“Basin”(? I suppose that that has a top on it.) measures: 110 X 50 X 20 cm.
About 1" inside the back “gable” there is a bulkhead “(avoiding low corners)”(?) to collect the filtered gas from above the upper ss grid on the mattresses. It is taken out near the lower right corner, fed back to the “gasgenerator righthand lower part for last condense separation”(?) before rising up for re-heating in a “smuggler cannister”(?) before final paper filtering on the back side of the gasgenerator.
(identical bucket as for the twin cyclones). From there over the rised trunk lid on the right side of the basin to the right hand windshield pillar and down into the right wing and finally into the motor compartment.
Condense is taken out from the basin in the righthand lower corner with a 1 1/4" rubber tube to the bottom end of the “condense separator” (?) for the gas at the gasgenerator’s righthand lower part. (There is an internal bottom between the condense separator for gas and the condense tank proper). They have individual draining.
Can someone understand this and make it clearer to me? Skizzes, sketches, or pictures would help. TomC
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Ok, let me try another question. I am testing my system for air leaks using vacuum. I start out with my kirby vacuum pulling 16 inches of H2O. When I check the vacuum at the mixer box at the engine, I have only 3 in. My question is NOT, “why do I have such a loss”, I will have to sort that out. But my question is " why when running on woodgas, do we get a reading on the cross rail of three times that of the fire box?" When testing I start with the 16 in. then anything I add affects the entire system. Starting with 16 if I add my hay filter, the vacuum coming out of the Kirby drops to 14 and the vacuum coming out of the hay filter is 14. No difference. If I add to that my cooling rails I get 11 at the Kirby and 11 at the cooling rails out let. No difference between the start and finish. So how do we get the rails to read three times the fire box.?TomC
I never trusted vacuum readings when testing for leaks. I always use soap solution with low pressure air - low enough to not blow the bubbles to pieces.
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Yes Don I agree, always used soap and pressure. This all started when I tried to start and flare the gas generator. Couldn’t get anything to happen. Not even smoke in the hopper. That was unusual, so I started this journey of taking the system apart and trying to test each part of the system. I did find two leaks so maybe I will put it back together and see what the engine will pull. TomC (individually I have not tested the cyclone alone or the generator itself.)
Tom, I´m not completly familiar to your vocabulary, but I guess you by “firebox” mean somewhere in the nozzle region or hopper.
As I understand it the difference in vacuum represents drag created by the charbed and its chemical activity. I like to think of the hopper vacuum as the vacuum nozzles are seeing.
With an extremly tight charbed hopper vacuum will be close to zero and you will peg the rail guage. With an empty gasifier the readings should be about equal.
Maybe i missunderstood your question. Feels like I´m kicking in open doors here.
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Hello JO. When you say it, it makes perfect since. I have one vacuum gauge in the cooling rail and the other is in the ash area by the grate. From what you are saying, I should have the one in the hopper instead of the ash pit.
But I still get that 2 or 3 to 1 ratio of rail to ash pit. Hmm. Seems with my set up the rail and ash pit should always read the same.
Quick description of my problem. I have a “Y” with two legs taped off and the kirby vacuum in the 3rd leg. A tap in the “Y” reads 16 inches of H2O with Kirby full blast. Now I hook everything up to the “Y”, with tape across the air inlet to the gasifier and tape across the outlet from the mixing box under the hood; the vacuum reading at the tap goes to 3 inches. Go back to the “Y” and tape one leg off and connect the hay filter to the other with the exit to the filter taped off-- 14 inch reading. Then remove tape from filter exit and put a 7 ft piece of 3" pipe on the outlet with tape on the far end— reading goes to 13 inches H2O. And down and down it goes as I add cooling lines, cyclone, gasifier, and line up to the mixing box at the engine. Ending in the 3 inch reading.
Can’t believe I have consistent air leaks through out. The 7 ft pipe I took out and made sure there were no leaks.
Tomorrow, I will pressurize the system, but the little I got done on that project tonight showed it ain’t going easy. TomC
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Hmm l am not quite sure what to think of your problem. You shuld have roughly the same vacuum after the gasifier. Cyclone takes about 2" if l remember right, not sure of the filter but the rail and gas suply piping shuldnt be wery restrictive. Soot plug perhaps?
What JO sayd. Allso a note. Same quantity of gas trugh a cold gasifier hearth expands 4 times once the hearth is fully heated. Thats a lot more drag.
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Maybe I am confusing this whole thing because I am measuring “static” vacuum. I section off different parts, starting at the kirby, by taking the system apart and putting a plastic bag over the end of the pipe where it is disconnected. ( all vacuum readings are taken at the “tap” in the “Y”) The difference between the reading at the intake to a part and outlet, should indicate the amount of air leak. BUT, the 7 ft piece of pipe I checked very carefully before installing and yet I lost 1 inch of vacuum in it. indicating a leak.
I’m going to pressure test it like Don recommended. Being an OLD tire man, I have used that method a million times on tires. The problem is getting pressure in the system. Last night I put a air chuck connector in the cooling rail and taped the intake air to the gasifier off, and taped the pipe coming out of the mixing box to the throttle body. Set my air compressor at 2 PSI and connected the hose to the air chuck. I could hear a “bad” leak in the gasifier, particularly the hopper. What is in the hopper that could leak and where is the air coming out. After going to bed, I figured that out. The air flowing into the hopper was making the noise and it takes a LONG time to fill a 50 gal. drum with water if you are using a 3/8 th hose. That is what I was trying to do with air. The sogga to continue. TomC
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Hello Tom.
Just another thought on leak checking.
I worked in the high vacuum industry many years ago and one way we checked for leaks was to pump the system down, then seal it off (closing the valve to the pumps), while measuring the pressure (vacuum). If there are no leaks, then the pressure won’t change.
Pete Stanaitis
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Thanks Pete. That is what I was trying to do. Seal off both ends and pull a vacuum, but I couldn’t get it to hold, it leaks down so fast it takes a constant pull.
You just made me realize, that I am pulling a vacuum, but then I just shut the electricity to the vacuum source off. I should have shut the valve to isolate the vacuum pump from the system if I want to hold a vac. It was probably beading down through the vac.pump itself. Thanks TomC
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Can’t find a specific thread for themo couples== So asking here. Can I cut the wires going from the probe to the meter and add or subtract wire to reach my gauge or so I don’t have excess wire in the cab? As I understand we are working with “mili amps” and am concerned that a splice will add resistance or removing wire will lower the resistance. TomC
We are working with millivolts so amps are insignificant. You can add wire if it is the " thermocouple wire" of the same type as the TC. You can buy type “K” wire on ebay, I recommend solid wire with non-fiberglass insulation. Fiberglass is woven and will unravel too easy. 
. It is not copper, but an alloy. Wire nuts are easy to splice. Cut off excess if you like, or coil it up. Wire size is not critical, but a little bigger solid is easier to work with.
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Thank you Carl, I thought someone was selling TC wire at Argos the first year, but was concerned because we are dealing with “mini-” I have not had good luck with those “readers” that most of you use and am going to try JO’s meat TC but the wire is way to short. TomC
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I know this isn’t a "thread on thermocouples, but----
I have written a bit about Thermocouples that I have used with my own woodgas reactor here:
https://www.spaco.org/Woodgas/thermocouple%20calibration/thermocouple%20calibration%20for%20woodgas%20reactor.htm
This page has several real world examples, and offers hints on how to stay out of trouble when buying off of Ebay, etc…
For those who need to extend the length of the leads for a T/C they already have, there is a full range of:
“thermocouple extension wire” (google that) available. And there are several companies on the net that have very instructive websites,
https://www.omega.com/section/thermocouples.html is one of them.
https://www.thermocoupleinfo.com/thermocouple-wire.htm
Having said all that, I have found several sheathed, Type K T/C’s with “3 meter” leads. That, of course is about 9 feet, and so would not require any extension wire for most of our applications
Pete Stanaitis
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Thank you Pete for the info on TC’s. I have had bad luck every since I bought my first TC’s and readers— I know price was a factor in what I chose. The TC’s were the ones with the 3 meter length cables. From what you have told us, maybe I can buy some better TC’s even with shorter wires and add on. TomC
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Hi, Tom!
21.12.2017
Reinstalling W10 64-bit + Firefox 64-bit + Chrome 64-bit.
Firefox stumbles with archive searching, does not find what i want!
Chrome works in a humble “seviceminded” way, brings up what is asked…
Happy Christmas!
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Good too se your still kicking MAX, I feel like kicking the bug thats going around these days, If i could pin it down. Happy Chrismas. Max Gasman AND TOM,Collins.
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