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Today I ran my Aerovee engine for the second time. My throttle is stuck when the engine is running.

The first time I ran the engine (a week ago) the throttle was stuck with the engine running and I was getting strange numbers on my Xtreme. So I shut down the engine. I noticed that with the engine off the throttle would stick a little when you first started moving it from the idle position forward.

I did a post to the forum about the Xtreme settings and got a great response ( Thanks Mike). I setup my Xtreme with the settings from Mike's response and today the readings I got appear to be correct.

On Thursday I dug into the Sticking / Stuck issue.
I first wanted to check if the bend in the cable might be too much. So I disconnected the cable at the throttle and pulled it out of the firewall. I held the cable straight out in front of the aero injector. There still was the sticking when first moving the cable from the idle position.
Next I took the aero injector apart to see if anything was in the area of the slide. The area was clean and free of any debris. The slide would stick a little when I would move it with my finger.
I removed the needle. I tried polishing the needle a little. I put the needle back. The slide seemed to then move smoothly. So I put everything back together. The throttle moves smoothly with out the engine running.

So today I was able to run the engine for a second time.
It started right up (just like the first time) but the throttle was still stuck. It would not move at all.
The RPMs was showing around 1400. The oil pressure was 38 psi. The oil temp was 89 degrees.
I let the engine run for about a minute. The throttle would not move.
I shut down the engine and the throttle would move smoothly.

I purchased my Aerovee 2.1 kit in March 2011. I know that they have changed the throttle cable since I purchased mine. So I have ordered the new cable to see if that makes a difference. I don't know if it will make any difference but I will give it a try.

Has anybody had a similar problem?
Anybody got any suggestions on what I should try?

Thanks

How do you have the cable routed?

-Removed-

They have also changed the mixture design since then which includes a nylon bushing where the mixture needle enters the body. You may want to ask if they can update yours.

Dana, I have the cable in a gentle loop from the firewall to the front of the cowl and then back into the aero injector. The aero injector is turned with the throttle cable facing the front of the aircraft. When the engine is not running the throttle now moves very smoothly.


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Yes, my throttle stuck in the wo position and I hit a snow bank before I could stop. It cost me a prop. The cable was smaller than the replacement and it would buckle between the throttle arm and the cable sheath without pushing the cable at all. The heaver cable solved the problem.

Onex107 wrote:Yes, my throttle stuck in the wo position and I hit a snow bank before I could stop. It cost me a prop. The cable was smaller than the replacement and it would buckle between the throttle arm and the cable sheath without pushing the cable at all. The heaver cable solved the problem.

I am also using a solid piano wire. Can't remember the diameter.

If your throttle cable is working freely, it's probably suction raising the slide upward causing friction against the body. With the engine not running, push up on the slide from underneath and have someone operate the throttle and see if this is your problem..........................Tom Ryan 0nex 74

I had an email from Sonex this morning. Kerry said it sounded like I had tried all the right things. They are going to send me a replacement. So I will give that a try. Hopefully between the new cable and the replacement It will solve the problem.
Thanks to everyone for their help and suggestions. I will post more when I try the replacement.

Hi fellas.. ..wondered what the current thinking is regarding heat treating of the stainless exhaust? any con's, other than the obvious regarding the cost?