Hi folks - first time posting here as I've got a bit of an intermittent problem.
Purchased a 2002 finished RV-6 back in Feb 2018.
From when we bought the aircraft until about a month ago, the engine would fire within 2 turns of the prop - fantastic. Now up until the time it started misbehaving here in the UK we had crazy hot and dry weather for about 8-10 weeks - so initially we though atmospherics were to blame.
Around the time that the temp dropped back to normal UK summer levels, we noticed the engine becoming harder to start, as well as the odd backfire (afterfire) when doing mag checks at high RPM when turning the Plasma off and checking RPM on magneto only (the LEFT key position).
We're now at the point where the engine can be very hard to start, often kicks back after letting go of the starter and when it finally does start, seems to do so after you've let go of the starter switch and gone to BOTH with the key. There is no sign of combustion most of the time, no popping from exhausts.
When the engine is running, it performs fine and the 'mag' check on both sides is normal.
Things we've checked so far with assistance from an LAA Inspector
Our next line of enquiry is the carb idle adjust, because the bottom plugs should be igniting the fuel and air. If this proves fruitless we will probably investigate the key switch and maybe contact Klaus about the Plasma - he might know more.
I'd be greatful for anybody who has experience a similar situation. I have seen one other thread about an RV that started after you release the switch, but that was dual mags and obviously switch related.
Purchased a 2002 finished RV-6 back in Feb 2018.
- O-320 D1A
- LSE Plasma 1 unit on the right (top plugs)
- Slick Mag with impulse on left (bottom plugs)
- ACS starter switch
From when we bought the aircraft until about a month ago, the engine would fire within 2 turns of the prop - fantastic. Now up until the time it started misbehaving here in the UK we had crazy hot and dry weather for about 8-10 weeks - so initially we though atmospherics were to blame.
Around the time that the temp dropped back to normal UK summer levels, we noticed the engine becoming harder to start, as well as the odd backfire (afterfire) when doing mag checks at high RPM when turning the Plasma off and checking RPM on magneto only (the LEFT key position).
We're now at the point where the engine can be very hard to start, often kicks back after letting go of the starter and when it finally does start, seems to do so after you've let go of the starter switch and gone to BOTH with the key. There is no sign of combustion most of the time, no popping from exhausts.
When the engine is running, it performs fine and the 'mag' check on both sides is normal.
Things we've checked so far with assistance from an LAA Inspector
- Impulse coupling clicks as it should when turning the prop.
- Magneto is firing the bottom spark plugs - visual check of each plug when cranking, (so surely the key switch must be fine?).
- Fuel is getting into the carb (M4-SPA) from the electric pump and throttle accelerator pump.
- Cranking engine with the Plasma unit circuit breaker pulled = no start but no kickback.
- Cracking with Plasma live = kicks back 50% of the time.
- Installed bigger battery = no improvement.
- Injected fuel direct into cylinders with a syringe = no noticeable combustion.
Our next line of enquiry is the carb idle adjust, because the bottom plugs should be igniting the fuel and air. If this proves fruitless we will probably investigate the key switch and maybe contact Klaus about the Plasma - he might know more.
I'd be greatful for anybody who has experience a similar situation. I have seen one other thread about an RV that started after you release the switch, but that was dual mags and obviously switch related.
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