• Welcome aboard HomebuiltAirplanes.com, your destination for connecting with a thriving community of more than 10,000 active members, all passionate about home-built aviation. Dive into our comprehensive repository of knowledge, exchange technical insights, arrange get-togethers, and trade aircrafts/parts with like-minded enthusiasts. Unearth a wide-ranging collection of general and kit plane aviation subjects, enriched with engaging imagery, in-depth technical manuals, and rare archives.

    For a nominal fee of $99.99/year or $12.99/month, you can immerse yourself in this dynamic community and unparalleled treasure-trove of aviation knowledge.

    Embark on your journey now!

    Click Here to Become a Premium Member and Experience Homebuilt Airplanes to the Fullest!

Stuck valves

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

PTAirco

Well-Known Member
Joined
Sep 20, 2003
Messages
4,006
Location
Corona CA
I had my first stuck exhaust valve on an O-300 in my Maule M4. I've flown this quite a bit and most recently a couple of days ago. My friend borrowed it and flew it to Big Bear. Stayed overnight and flew it back in the morning. Barely got off the ground... Luckily it's all downhill to Flabob from there. He thought he was running on five cylinders. No, he was running on four. Two rear, left cylinders had no compression when I pulled the prop through after he landed.
Nothing unusual in one stuck valve but two!?!

We're doing the usual rope-trick fix. What I'd like to know is how to prevent it. People swear by Marvel Oil or TCP or even two-stroke oil. I have on occasion used MMO, based on the ton of anecdotal evidence out there but not on a regular basis.

The engine does not run hot generally , neither oil not CHTs. It was about 100 degrees here that day, but the seizure happened when it was pretty cool p there.
 
Back
Top