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Topic-icon 2006 32R 301 Saratoga II TC hot start problem

  • Andrew Campbell
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2 months 1 week ago #1954

Starting from cold is never been an issue, prime for 7-8 secs and away she goes, however, try and start her within an hour of shutdown and it’s totally hit and miss if she’s going to start before the battery bus voltage drops below what the Avidyne Entegra needs to function. I’ve tried the POH method and one suggested by a friend, and nothing works successfully every time. It’s quite embarrassing when you've pulled up on the pumps to refuel and then have to push her off to one side. Can anyone help???

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1 month 3 weeks ago #1992

Let's start with the fact that you're not the only one experiencing this problem. I've seen it many times.
The following are a couple of techniques that are often mentioned.
First and simplest is to push throttle full open; pull mixture completely back. Crank engine. When it starts to fire pull throttle back and push mixture forward.
Second method is to flood the engine so you know what fuel air state it's in, then work backward.
Here's how. Full rich mix, boost pump on for 5 to 10 seconds. Then 1/4 throttle, mixture half way forward, boost pump on. Crank engine until it fires then pull throttle back to idle rpm.
A third method is throttle, full; boost pump, on; mixture, move from idle cutoff to full rich for one second, then back to idle cutoff; boost pump, off; engage starter. Once engine starts pull throttle back and push mixture forward.
Unfortunately, a couple of these methods seem to require three hands. You'll develop a step by step plan that works.
One of these should provide you with a dependable and reproducible starting procedure.
Happy Flying,
Steve

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1 month 3 weeks ago #1993

Starting a Lycoming fuel injected engine can be problematic. The core of the problem seems to revolve around the fact the stainless steel fuel delivery tubes located above the cylinders are exposed to high temperatures after engine shut down. This tends to cause the fuel in those lines to vaporize, creating a fuel/air mix that’s a combination of vapor—which is very hard to push with a fuel pump since it’s compressible—and liquid fuel.

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  • Andrew Campbell
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1 month 3 weeks ago #1995

Hi Steve - many thanks for your starting tips. I shall try these in the comings weeks to see which works the best.
Regards
Andy

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4 days 49 minutes ago #2059

Everyone has suggestions for hot starts that involve the fuel/mixture system. For my Cherokee Six, the solution was in the ignition system. The solution, and this made a huge improvement, was to replace the spark plugs powered by the impulse coupler (I think it is the left on my aircraft) magneto with fine wire plugs. This was done on the advice of someone at Lycoming. After years of hot start problems, that had defied multiple mechanics, this was the answer. I can now reliably start when hot using conventional hot start techniques.

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3 days 21 hours ago #2062

Hi Joshua - thanks for taking time out t reply to my hot start issue. As you say, the standard hot start methods include fuel/air solutions. I must say that although I've only need to hot start on one occasion since raising this query, one of the methods put forward by Steve, actually worked.

I shall continue to use this method and assess whether it really works or whether it was a fluke. If I still continue to have the issue I will certainly be talking about your solution to my engineers.

regards

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