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Starting inverted engine?

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Old 07-04-2012, 06:37 AM
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pjwilletts
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Default Starting inverted engine?

I have a pumped 120 glow engine mounted inverted that floods and isvery difficult to start..any suggestions?
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Old 07-04-2012, 09:03 AM
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Default RE: Starting inverted engine?

I'm not an expert on pumped engines, but on regular glow engines, I usually don't have any problems.

The first question is: What adjustments have you made already? Can you go back to square 1 and start again?

The next question/suggestion was whether you ever had this tuned to run perfectly in the upright position before you mounted it, especially in the idle region.

These are just for starters. Just my $.02

Bob
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Old 07-04-2012, 08:55 PM
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Default RE: Starting inverted engine?

the engine ran fine upright and side wayse...i think the problem is that too much fuel is being fed into the cylinderthan the plug can burn off..
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Old 07-05-2012, 05:02 AM
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Default RE: Starting inverted engine?

When you had the engine upright, how was the idle. was it lean enough so that you wouldn't pool fuel into the cylinder? How was the transition.

As for adjusting the pump (if needed) I can't talk to that. I had just noticed that when I used an inverted glow, if it wasn't set up right it would usually richen and die on me.

Also, how was the humidity when you were doing the tests? Out here we've had high humidity recently and it really affects the tuning of our engines.

Bob
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Old 07-08-2012, 09:24 PM
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Default RE: Starting inverted engine?

It may help if you use a glow plug with an idle bar. Second, don't choke and turn the engine over before trying to start it. Leave the engine dry and just hit it with the starter.

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Old 07-08-2012, 10:21 PM
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Default RE: Starting inverted engine?

I've had good experience of starting the engine upside down on a stand (with an inverted engine). Simple & efficient 100%
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Old 07-09-2012, 09:43 AM
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Default RE: Starting inverted engine?

When an engine is mounted inverted, the height of the carb in relation to the fuel tank can change. If your carb is lower when the engine is mounted inverted, you can (will) get siphoning. You may have to change your tank height to make this work properly.
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Old 07-09-2012, 11:02 PM
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Default RE: Starting inverted engine?

as RV 7 garage Says tank location is important. The tank centerline should be about 1/4 inch below the carbs spray bar....If you are to far above you will get siphoning and flooding...This is espially important in inverted engins because fuel runs to the lowest spot and floods the glow plug.... You need to be really carefull here too because you can easily hydrolic lock your motor and bend the rod when trying to start it...
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Old 08-13-2012, 01:21 PM
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Default RE: Starting inverted engine?

Check your pump for a valve leak, you should not be siphoning past the pump.
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Old 08-13-2012, 06:59 PM
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Default RE: Starting inverted engine?


Quote:
ORIGINAL: ddd

Check your pump for a valve leak, you should not be siphoning past the pump.

Agreed, a pump should not be flowing fuel until it gets pulses from crankcase.

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