Engine rough, run it up to 4000, she backed off, stuttered, etc.

[danielabernath]

(Yes. I know I don't know much but I have taken the course at Sebring and another light sport inspector course with Rainbow and I am trying to learn. So I am not a helpless metrosexual-I am learning).
When we last left our story, I had water/rust/volcanic stuff in fuel.
I hired a and p man who said that he would and did take out all the fuel to strain it. I had other issues so I didn't worry too much about the fuel having the foolish belief that when a man tells you something that he is actually telling you the Truth.
Today, I turned on the engine for the first time in a long time. Started up nicely but rough start. Then she was OK at the low RPMs. I gave her more gas and she'd stutter and was rough and then smoothed out. I figured that if there was any moisture that the engine was just running it through.
I got her to 4000 rpms and she dropped to 3800, then down to 3500, back and forth. If I gave less gas I got more RPMs. If I gave it more gas I got less RPMs.
Never got above 4000. She would just drop if I tried to get above 4000. Then I saw engine oil was getting hot, so I shut her down.
I then took another fuel sample after this running up and saw about 200 tiny brown grains at bottom. I threw that out and then took another sample and it was clear.
(the first sample I took before I turned on engine showed clear but with 3 or 4 little brown grains.)
OK. So I need to actually drain all that fuel out and give it to the guy who mows the grass at the airport.
Any suggestions here? I am not sure that the a and p man who said he drained actually did anything as he has turned out to be completely unreliable.

[krw5927]

If this junk made it to the carb bowls, then removing the fuel from the tank and straining it won't fix the problem. Might be time to remove the carbs and clean.

[rvbuilder2002]

Originally Posted by krw5927

If this junk made it to the carb bowls, then removing the fuel from the tank and straining it won't fix the problem. Might be time to remove the carbs and clean.

Yup.

Contamination within the carbs would be a high suspect with these symptoms.
The rotax carb has three different stages depending on throttle position.
It is possible for it to idle just fine but not run properly when you change to higher throttle positions.

[danielabernath]

I just had a&p man examine engine. He travels over Florida and works at the airports after working for Sebring for ten years.

This is what he said
1. remove Gasolator. 99% of the **** is there.
Use fingernail and take out screen. Blow on it after gasoline evaporates and it will clean right up.
2. look at the plans and find the screen going from the gas tank to the lines and do that the same sort of thing there
3. undo the carbs and look into the hole and clean out anything that it in there. Unlikely it made it that far.
For those of you who have been following this story/police reports/lawsuits he says that without a doubt, using motor car gasoline those two to three inches of corruption were "introduced".
(Got that Jonn? He'll be an expert witness at the trial)

[DonFromTX]

I don't know if you have come up with a similar feeling, but ever since your first post, the thought of sabotage has sure popped up in my brain often. I would want to find out just what those "brown grains" were and invest in a locking fuel cap. Several things you have had a problem with just don't happen by themselves. It used to be common for someone that did not particularly like you to put sugar in the fuel, can ruin your whole day.
On the other hand, if you have introduced dirty gasoline yourself that might be different.

[danielabernath]

I filled up at the fuel farm at KFMY and they showed me the records on how they test that fuel over and over again.

Don't want to go into details but I have made my displeasure at lack of sense of urgency on security to airport management.