Nitefrater

Lean AGGRESSIVELY on the ground - before and after flight, and use TCP.

If the students aren't leaning properly on the ground, it's because the Instructors aren't teaching them properly. Go to the source of the problem.

TheGeneralMcC

i've seen a lot of guys use that stuff in older radial engines. i've never seen it used in a horizontally opposed engine. i'm not sure what purpose it serves but some people sware by it.

msh168

In the old days, they used to throw some 5606 in there for the sticky valve problem.

MoosePileit

Few things at issue- Lead and spark plugs- TCP is great stuff, though noxious. If cert'd engine, you have to use the Alcor, not the generic version. You also can only use the spark plugs in the TCDS, though you may have a better option for lead buildup. Teaching the instructors to teach leaning is good- that gas and labor are pricey! The MMO in the radials is to replace the lead that would have cushioned the valvetrain in an engine that is low-compression enough to run autogas/MOGAS (no alcohol and STC and all).

I like MMO, I don't like tight valves that stick! Some valves will stick on MOGAS- they have good guides, just too tight for the carbon in the exhaust of MOGAS- MMO helps. 5606 probably is about 1/2 of what's in MMO, along w/ some kerosene and peppermint oil.

Lycoming Parallel valve engines that wobble in the valve stems will bite you.

Some engines will warn you w/ a little sticking at startup, ie morning sickness. Others will stick and you'll need the rope trick to unstick the valve or release the keeper, drop the valve, clean/ream, etc, then reset the valve and go from there. More for the little displacement continentals than larger engines, all w/ your mechanic.

peterpilot379

Have you seen this? From the Piper Cub forum.

http://www.pipercubforum.com/marvel.htm

spitfire1500

Back when I was working as a CFI the owner of one of our 172's who was a mechanic use to mix it in his fuel all the time and said it worked great....but he also mentioned the feds would frown on it if known.

stinsonjr

We used to put MMO in my Grandpa's airplanes - a couple Waco's with Jacobs R-755's and a Howard with a P&W R-985. He didn't do this when you could still get 80 octane, but then he did. Didn't use too much, but a lot of the old timers flying radial's swore by it.

t-cart

You mean to tell me the old 985 and 1340 will run without the MMO?

stinsonjr

I knew you would chime in - I figure you had as much or more experience as anyone here with the old radials.

To clarify, we only put the MMO in the radials - he had an Aeronca Chief that we did not put it in.

So, T-cart - did you use MMO in the Ag-Cats and recip Thrushes and Air Tractors you worked everyday and if so, where there any benefits to longevity, maintenance, etc.

Thanks T-cart!