Yes, pine has often high tar content. But birch is pretty rich on tar too, especially the bark.
Ideal senario is dry and hot enough to burn all tars, but nothing is ever perfect.
This is where hopper condensation comes into play. The more you can collect, the less tar and moisture the charbed has to deal with.
I remember watching a clip where WW2 truck drivers were interviewed and they all prefered alder because of very low tar content. I guess they all used non-condencing hoppers at the time.
Unfortunately you and I have only gray alder in our area and it’s extreemly bulky. It runs just fine but I get maybe 60% distance on alder compared to birch.
The wood I’m running right now is chunked last fall. 50% sticky spruce limbs, full of dried drops of tar. Lately I’ve collected more tar than ever in the hopper-juice tank.
A real bad one…
Ok, I think it has been a bit weak for a while, I have fiberglass string as a seal, and usually have copper paste on this, I should remove the paste, and have the string as it is, or how do you do?
Ash doors are always a pain. I like to eliminate them when ever l can and make them as small as l can when l need them. Easyer to seal a small dor thain a big one. And you only realy need a tiny opening to scrape the ash out…
I have tryed many things and not one worked good enaugh for me. I ended up just applying fresh silicone at each emptying.
Jan, If I ever make a next build I was thinking a 3" pipe, long enough to shed most of its heat and just a rubber cap.
Rubber cap or maybe find a Rigid Conduit pipe in 3" size and get a 3" npt plumbing cap. Though plumbing pipe threads are tapered, Rigid Conduit is the same thread pitch as plumbing NPT spec. Add some high temp RTV on the threads and it might work great.
I tried silicone before on the old fire tube, but got too hot so it melted.
Do not think it would be so hot, but it did not work.
However, it may be different on the new fire tube, will test.
Will see if I have any pipe and plug that would fit.
Thanks for the advice.
I tried with silicone, it seems to work on this fire tube, will go a week to see if it lasts.
I would like to keep the door to inspect the grate underneath, but I could make a pipe out through the door for ash emptying.
I apparently had more problems, the car went very badly I had to go on petrol, the vacuum gauge that sits on the radiator next to the cyclone seemed artificial, showed strange values, in the end I found the fault, it was the foam rubber in the filter that went against the tube to the engine.
Could not help but test the car then, it did 68mph on pine, but it was probably max.
Haha! Jan, you’re having too much fun. Watch out or you will have to redo your seal over again 
Woke up with a soar throat today. Covid test tomorrow morning 
Keep your fingers crossed that it is not covid, I will get the first shot on Thursday.
The pollen has been insane here. I keep having nasal drainage issues and I wake up with a sore throat. Hope it’s just seasonal allergies for your case.
Same here, the pollen in the air by the wind and bees.
Bob
I keep dirty enough to avoid allergies 
Probably a normal cold. They still exist.
As does that normal flue!
I inspected the car and horse transport last Friday. The horse transport went well but the car did not go well.
I got 7 faults on the car, one of which was too high co at idle.
The engine servic light also lights up, if I turn off the light it starts to light up after about 3 km.
I do not know if I have obd1 or obd 2 on this car, it is a 1995a, 4.3l, but has an obd2 connector.
Do any of you know how I can see if it is obd1 or 2, I want to buy a reader so I see what the fault is that makes the engine servic light on, the light must not light on the inspection.
aldlcable.com
JanA you most likely have a transitional system.
It has OBD1 software talking through an OBD2 plug.
Translate and read this article for,
“Some 1994-95 cars have the 16 pin OBD2 connector . . . . Even though it has an OBD2 connector, it has an OBD1 (coding and communications speed) system behind it on these 94-95 cars.”
So break your problem down into two steps.
- get your running tail pipe measures CO reading down below the mandated threshold.
You can Internet search up “reasons for high idle CO readings”. Only use the professional advices. - Get a system to be able to read/scan your system to see WHY it thinks it needs to set the Engine Service Light.
A cheap easy OBDII plug in scanner may not be able to read your system.
I am sorry I am not able to detail read/translate your picture of your 7 listed faults.
ALDL is pure General Motors “speak” about their data reading plug. It means, “At the end of the factory assembly line quick check: all systems OK? quick connector”
S.U.
Jan, in my opinion there’s nothing wrong with your truck.
In Alabama you could keep on running as is. I was under the impression things worked the same in Grängesberg
Thanks Steve.
I’ll see if I can make a cable that can be used, a pity that I can not use the same way as with an osb1 connector, and test with a paper clip.