Kristijan; That was over 40 years ago when catalytic were new. I think the first one we towed to the Ford garage and they found the problem. After that we pulled the exhaust pipe apart some place ahead of the muffler and cat converter.
Back to the caked up intake. Remember if you hold your nose and try to breath, your ears will pop and you can feel a pull on you eyes. Something when the intake is plugged. The pistons will try to pull air in anywhere it can airy-ate the oil and possibly cause the problems in the breather and vents.
Iām sure your frustrations will all go away when you finally find the problem and correct it. I hate to hear you say āoh, it is running better nowā without really finding the problem. I have found that cars are not like animals ā if an animal is sick it either heals up of dies. A car does not heal up. TomC
Years ago a friend told me that his car bogged down and had to be towed to a garage where they declared the engine was shot and the car had to be junked. I asked my friend if I could have it to play with if I payed for the towing fees. When I finally got a chance to check it out I found a clogged catalytic converter. I reamed out the catalyst core with a long screw driver and used the great running car as my daily driver for many years.
I agreed earlier with Andrew, but as Jo comments at times I may not be thinking at full speed. I have had experience with dying engines. The oil added compression test indicates variable piston ring performance, one would assume hard carbon deposits in the piston grooves. Hopefully this wouldnāt be interfering with ring lubrication, and presumably the carbon is somewhat of a lubricant. Tom raises very valid possibilities, hopefully more what he is saying about blocked catalytic and suction. Final theory is valves not seating perfectly due to carbon deposits
Here is what Iām using on my MG:I looked around on the net for stuff to free stuck rings. Acetone and automatic transmission fluid is most recommended. Marvel mystery oil also gets some good reviews. First, I drained and saved my good oil (with antique car ZDDP additive). I mixed up some MMO, ATF, acetone and engine flush. I poured this magic potion in the cylinder with piston coming up on compression. I fashioned an air compressor to spark plug thread adaptor and air blasted to push the penetrating mix past the rings.
The last time that I drove it there was less smoke, so Iām hopeful. I filled the cylinder again with the magic potion when I parked it for the winter.
Bruce, l went your route. Added about a cup of diesel to the crankcase yesterday. Today l tested different solvents to see wich one works best on soot cake, and found both alkohol and acetone are incredible at it. So l filled the bad cilinders with a few tablespoonsof the mix and let it sit in for about 3 hours. Upon starting the engine l saw a slight reduction in gas expelled trugh the valvecover vent. Filled them agen for the night, will see tomorow.
Now, l think l might fix the problem to a point. My question now is what do you guys think on cleaning the intake manifold? My thinking is since the acetone/alkohol did such a great job on the soot, why not dump it in the intake manifold with engine running to clean it? Any thods?
Kristijan, the thing that would worry me is if you get a backfire. What will happen to that plastic intake then? Soot soaked in acetone sounds highly flamable. Make sure you can shut down fast and seal off all air if you decide to try.
Excelent point Jan! This calls for some safety measures.
The problem is, l culd pour acetone in and let the soot soften with engine off, then flush it with steamy water, wut l dubt engine will start with a inake manifold full of acetone and broaken down soot.
Cat converter plugging is tested by drilling a small hole in the exhaust ahead of the Cat and pressure testing with an H2O scaled pressure gauge. Self-tapping screw plug-able.
Net search for recommend back pressure specs.
Sometimes the pressure will only occur with fully heated up EXPANDED Cat core. Ha! Melts the gauge hose if left on to check! Use a metal extension, heat-radiating stub, as the tap fitting.
Any ārattleā cold to hot, hot to cold, in the Cat core means it is worn loose. Loose core hammer damages the ceramic core passage ways shut. Rattle noisy - is a bad Cat.
J-I-C Steve Unruh
This is a good time to mention that Sean French once told me he melted a cat after many miles of woodgas service. Plugged it solid shut, he said due to the soot over-fueling the catalyst. I donāt think youāve got enough miles/km on wood yet but itās something to keep in mind.
All the trucks Iāve had on wood have had the cats removed by previous owners. No inspections/emissions hereā¦
Iām not sure anyone has suggested this. I see a lot about clogged cat convertors, however a performance problem that vexed me for a bit was a collapsing muffler. Disconnected exhaust pipe from muffler and found it severely rusted inside. Started car, the car ran great. Installed new muffler, car ran great.
Pepe
Hi Kristijan, sorry to hear the problems you are having. When I pickup my truck and drove it back home from Kentucky to Washington State, 3000 miles. I noticed it did not want to go any faster than 57 mph. I could tell it was missing a bit and it was a rainy day.
Chris had given it a tune up with new spark plugs, wires, rotor cap, and rotor, also a oil change. In the 3 1/2 days on the road it just keep running better and better on dino. Chris had ran this truck for months at 100% wood gas, even on start ups.
Going through Montana I was driving the truck at 85 mph trying to keep up with traffic, speed limit was 80 mph. I just had to burn all the carbon build up out of the engine, Valves and rings and anywhere else where carbon had collected.
When I got home I changed the oil. WOW! That was the blackest oil I have ever seen, it stained my fingers black. I change it again after a 1000 miles, black oil but not like it was before. I did one oil change when the truck had the new pentium plate put on the intake. Oil is fine now.
Inside my intake it was really Carbon up, had to chip and wire brush to clean it out. I had burned my intake out a couple of times but I could not get all the carbon out. It runs even better now with a new cleaned out intake. I have no cat converter on my truck.
The problem was carbon building up on the valves, causing the poor performance, maybe rings, and in the intake.
I would run your car on dino for a while with oil and gas additive to see if it will clear up. Check out Muffler and cat converter like the others said. Hope you can clean out the intake by just using the hot water method removing it is going to be a job. I Hope and pray that it will work out by just driving on dino for a while. Best Wishes to you.
Bob
Thanks guys for all the input. Realy helped me out. I am planning to take off the cat anyway becouse the flex joint needs replaceing (thank god the inspector didnt notice it) and will inspect everithing then.
Ok today l drove a bit to heat the engine and dispach the oil/diesel mix trugh the engine and drained it. Black like hell! Then filled the crankcase with 3l of pure diesel, started the engine to idle for 10s, still black. This procedure was repeated 3 times untill the diesel drained rather clean. Put new oil in.
The resault? Engine runs better, and the crankcase vent expells much less gas. Allso, today a coworker mentioned that he smelled oil when l drove by. Today l asked my wife to crank the engine with my face at the tailpipe (looked ratrer suicidal ). No smell of oil.
Compression went up on all 4 cyl, althugh 2 are still worst thain the other 2. Well not ideal but better.
Question: what do you guys think, what is No1 cause for such happenings?
My thods are tar, soot or woodgas itself (forming carbon at high pressure)
Tar l think is most possible, but it beats me that l have never seen any tar anywhere else in the assembly.
I believe tar goes into the engine as moisture. And then as the moisture comes into contact with high temperatures in the engine, the water is boiled out and you are left with just tar. As this builds up on the valve stems it causes them to stick and click or bend or I even had one break. When I took the intake manifold off, there was puddles of black tarry liquid which could have been all the black that accumulated in the diesel. So I guess you could have gotten tar in the engine. I was convince your problems was soot, but thinking back I remembered the moisture with the tar. A good reason for Maxās hot / paper filter. TomC
The mechanicle step i dont know if you tryed yet, is since it is posible that the head gasket is leaking between the oil ports of the block. You should preasure ize a the cyclinders one at a time and see if there is air psi excapeing out the rocker oil cap.A head gasket would be an easy fix if it was starting too leak. I have had a lot of old cars running good then next thing i knew it was blowing oil. so it may not be wood gas related.Good luck finding and fixing. Still the papper filter seems like a good reserve space for cleaner motor fuel.
I made a post above about a possible plugged muffler, but didnāt mention the symptons. I left home for Mass. and was driving to Burlington, Vt. The car was running fine for the first 25 or so miles. Then it began to lose power and slow down until I could barely coax 15 mph out of it. Turned around and coaxed it back home, took forever! My neighbor lent me his car and we went about our vacation. My father-in-law told me about the possibility of a plugged muffler, thank you, Brian! RIP my friend.
Tom, good theory. l did see a couple of backfires (or shuld l say frontfires?) when cleaning the engine. Heared a few popps. lll do a compression test with oil on the pistons once again.
Allso, I was talking to JO the other day, and he made a reasonable asumption, pellets burned in the gasifier might allso contain components like glues to hold them together. This might allso produce tar. Pitty. l loved them. Such good performance and range.
Kevin, your theory is allso possible. It is possible l hidrolocked (or near hidrolocked) the engine unnoticebly in this wery cold weather with lots of water condensed in the sistem over night. This culd ruin the seal.
Pepe, I had a friend on a visit a few years back, a scoolmate, with his first generation Renault Clio. He sayd the engine is overheating and doesent drive well. I went for a drive, then reved it up in neutral to max, it calfed out peaces of fiberglass and catalist trugh the tailpipe. He later reported the muffer had collapsed, and the catalist burned to a point there was no more in side
I have had experience with dying engines. The oil added compression test indicates variable piston ring performance, one would assume hard carbon deposits in the piston grooves. Hopefully this wouldnāt be interfering with ring lubrication, and presumably the carbon is somewhat of a lubricant. Tom raises very valid possibilities, hopefully more what he is saying about blocked catalytic and suction. Final theory is valves not seating perfectly due to carbon deposits
). No smell of oil.