That only gives you the circumference of the holes. Here is a calculator
https://www.google.com/search?q=area+of+a+circle&rlz=1C1CHBF_enUS831US831&oq=area+of+a+circle&aqs=chrome.0.69i59.5531j0j7&sourceid=chrome&ie=UTF-8
I come up with 3.79 inches with the four 14mm holes and 2.64 inches for the 6 3/8 holes. So quite a difference.
What I have learned and this is a general rule for me. If the unit is running hot and or the gas out is hot. That tells me the unit is too small for the application. Not enough charbed for the reaction zone and to much air velocity.
I find when the units work best they run very cool and the gas out hose is just warm to the touch, cooler than bath water. When they get hot the gas seams to be weaker and less stable.
It runs extremely cold in the gas exit. When running tests with just the blower the hopper area got hot but with the cherokee test it didnāt even get warm. But I couldnāt produce enough gas to sustain it.
What is the area of charbed (nozzle to grate) and how far apart are the flutes?
The engine should pull harder than your blower so it sounds to me that your fuel flow is too fast and may have too much velocity.
For my 420 cc generator the jet nozzle area is roughly 0.8 inches. So if we use that and scale it to a 4 ltr. I get a total area of like 7.61 inches. The char bed area is roughly 1200 square inches.
Now you will need an adequate charbed to match that much air volume.
Iirc the nozzles are 10 inches from each other as far as flute to flute goes.
Distance from nozzle to grate is about 10 inches with a 10 inch diameter burn tube made of ceramic wool.
Iād have to go back to one of my posts to remember the measurements.
Or you have an air leak your not seeing. I had a similar issue, where I could not get the small 79cc engine to run. It was hard to start and then once I could get it running it would run good for about 5 minutes and then it would just die out. It was a melted hose couple from the gas out getting too hot.
Thats way too small for a 4 liter I think. That is less than the size I am using to run a small engine. To run a 4 ltr engine you would need at least four of my Utility gasifiers networked and that would be the minimum. The Utes are only good for around 500 cc at 2000 RPM. After that you start to overdrive them.
Not sure. Itās all inside of a 55 gallon drum. I have about a 30 gallon char capacity above the flutes for fuel. I made the burn tube that diameter by just coiling in ceramic wool so I can widen that. I also have a brake drum just dropped in like a choke plate and I think that could be choking it too much.
Iām having moisture with the gas so thatās why I narrowed the burn tube and added the plate.
The Makos also had a 10" nozzle to grate distance, not sure about the diameter of the area below the nozzles.
Also to be fair this was originally specced for a 2 liter engine. Iām just trying to test the flexibility of this specific reactor.
Nice if you take my calculations. I came up with 3.79 inches for the 14 mm holes. Then going off of my systems and scaling up to a 4 liter I came up with 7.61 inches. So for a 2 ltr divide that by two and it comes to 3.8 inches. 
So I would say the 4 ltr is way to big. You would probably need to build a second unit to run it. Small engine probably will not pull enough velocity to sustain the localized reduction zones and is probably where the water is coming from.
Edit: Oops I was using diameter instead of radius for the calculations.
Recalculating!!
Ok 14mm = .55 inches area = 0.23 x 4 = 0.92 total area (for the 2 ltr engine)
Ok 3/8 .375 inches area = .11 x 6 = .66 total area ( quite a bit smaller than spec)
Ok now my spec for a 500 cc engine based on current jet size Im using now is . 0.79 total area. For a 2 ltr I come up with 3.16 inches.
I would never attempt running the M-1 Ute on an engine larger than 500 cc. It would surely overheat.
So what nozzle holes should I increase to? If itās even possible to salvage this specific build by just drilling out the flute holes some more.
I come up with 6 half inch holes to match the 2 ltr spec based on the info you gave me.
I still think that is too small but your build is a different animal than mine. So make one change at a time and learn.
Im trying to figure out the Gas CFM. Using gasoline carb CFM charts I come with 102 cfm intake air. So if that is the air volume intake then the gas should be roughly 3 times this. Im sure it is less than this in the real world. But just for perspective if we take the 102 multiply this by three 306 cfm then divide by 60 seconds thats 5 milk crates of gas the engine sucking in very second!!!. Try to imagine 5 milk crates getting shoved in through your carb every second. Thats not including your intake air. So now try to envision your gasifier making that much gas pr second.
Well luckily i made it with the intention of it being a test bed. Flutes are just ultra red RTVd into place. If I get too frustrated Iāll probably just make them into updraft flutes on a different barrel.
according to the GEK Wiki the air ratio in to gas out is a 1 to 2 ratio. So 1 CF of air = 2 CF of gas coming out. Dont know if this changes for char gas. Im sure it is different but probably good enough for reference.
So to produce 5 CF pr second you would need to suck in 2 1/2 CF pr second via your jet system. Now you can try to visualize the velocity of that 2 1/2 CF flying through your jet system.
Would this be of any help here? It is a spreadsheet for calculating nozzle size which Koen did some time back:
https://drive.google.com/file/d/0B4CL3bqit0osdHU3OVMyeE1yeHM/view
While taking char out of my double flute tester to remove the choke plate I noticed the deeper I went the more I saw this silvery colored charcoal.
I Cody, when you drop it does it make a glass like sound?
Bob
More of a glass sound than my other char does. About half of my char sounds like good breaking glass and the rest sound like dull pottery. I suspect the dull sounding char is from using deadfall wood that might be slightly punky.
