40 LA won't start hot

I have an LA 40 on a Tower Hobbies trainer. When I start the engine for the first time of the day it will start on the first hand flip. If for some reason the engine stops (I tip it over in longish grass sometimes) I can't get it started by hand at all and have to resort to the electric starter. After a flight if I let it sit long enough to cool all the way down it will flip start on the first try again. I think I have the engine tuned correctly but I'm no pro at it. Any ideas why it's such a pain to start warm? I know it's not a top of the line engine, is this just something I get to live with?

Thanks, Steve

Reply to
Steve
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I'm sure there's a scientific reason about how that happens but I always considered it " something to live with" like you said. If you have a starter wired to a box and or panel it's a pain. Get one of those batteries that attach to the starter so you can carry it to the plane easier. mk

Reply to
MK

There's a way to get it to work, it'll just take some trial and error. One problem with a hot engine is that it's hard to get fuel into the head as the heat tends to push it out. Before putting on the glow starter, you should try to re-prime it by putting your finger over the carb with the throttle open and turn the prop over by hand - be careful to hold onto the prop as you do this as it might kick back. It can take half a dozen or more turns of the prop to force fuel into the head, but too many and you'll flood it - that's the trial and error bit :)

You'll find there's some number of turns that gets the right amount in, and you'll be able to flick start it - I'd suggest you learn how to back-flick the prop (bouncing off the compression) as this is a lot safer than flip-starting as you can do it by holding the spinner instead of putting your fingers into the prop.

Reply to
Poxy

It's a very fine engine, and I have put hundreds of hours and many gallons of fuel through mine before I sold it to a friend who is still enjoying it.

It was developed by OS to cater to the budget buyer. You'll notice that many trainers have one sitting in the nose which keeps the price of the RTF within reason for the cost conscious modeler. Performance wise it will deliver an adequate amount of power for most 40-sized trainers.

Now back to the hard starting problem. I have read a couple of reviews that commented on the fine performance of the engine and its quiet operation; however, they both noted that the engine was impossible to start by hand hot or cold. In my case, I tried to start it once cold and nearly had a heart attack!

I don't bother with hand flipping, and I simply reach for the electric starter. Unless you use a cumbersome chicken stick, finger flipping is dangerous (just ask 7 fingered Sam).

Ciao,

Mr Akimoto

Reply to
Mr Akimoto

I'm curious...what kind of fuel are you using? All synthetic oil?? Or a castor blend? and what percentage nitro??

Reply to
Frank Schwartz

Probably because the cylinder expands too much when hot and the engine is losing compression. This could also be from an accelerated breakin.

Reply to
Paul McIntosh

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