Rebuilt 582 blue head.

[Methusala]

I've just mounted my 582 on the Thruster and have a strange problem! With all electrical connections made it runs but when the left mag is grounded the tach reads zero and the egt's show lower (by about 100deg C on one side). Also it is sluggish to build revs above 4000 and peaks at about 5,700. The cht's and egt's are not high at full revs (cht 65-70 and egt 520-560). I have substituted a known working CDI on both sides and makes no difference. Will next swap trigger units to see if that transfers the problem to the other side mag. Any gurus out there wish to chuck their ideas into the ring? Don

 

 

[fly_tornado]

Do you have a wiring diagram?

 

 

[Methusala]

Yes to that FT. I want to try swapping the trigger wires from one mag to the other in case one of the trigger sensors is FUBAR. I was really hoping that someone might recognise this from a similar instance. Compression and fuel appear ok and no nasty noises. Rotary valve timing definitely not the issue either.

 

 

[skyfox1]

Hi it sounds like you are only running on one ignition swap kill switch wires .

 

 

[Methusala]

I have now run the engine with the trigger wires swapped with no change to the situation. I checked the voltage running to each CDI unit from the alternator and they are the same. I will next check the grounding of the kill switches making sure that they give the best possible ground. Thanks Skyfox, I am also thinking that it most probably is an earthing issue. I will keep you posted. Don

 

 

[pudestcon]

When we were getting my T500 up and running we had to solve a number of small pesky problems with electrical issues. Most involved changing the earth return leads to dedicated wires rather than looping to a harness. Seemed to do the trick in the majority of cases. I would look in that direction first.

 

Pud

 

 

[bilby54]

Like Pud said, it is most likely an earthing problem.

 

I had an intermittent fault in a Drifter like you described and turned out to be a faulty terminal connection. It is quite possible that the earth lead from that magneto is earthing through other instruments rather than straight to frame and they can be mongrels to find at times.

 

 

[Methusala]

G'day all, today I substituted the cockpit mounted kill switch for another grounded directly to the engine block. No change! I think that the next (unavoidable) step is to replace the stator. Luckily I have 2 engines so I can substitute parts as required. Still you know how complicated this becomes when the engine is mounted on the plane and the fairly demanding ignition timing must be done again in situ. Stand by for any developments and thanx for your suggestions. It will probably be something that I have overlooked but what are hobbies for but to keep us thinking? Regards, Don

 

 

[skyfox1]

Hi Don have you taken out all the plugs and turned the motor over to see which plugs are firing or not that way you can track down which ignition is faulty.

 

cheers Geoff

 

 

[pudestcon]

This has got some useful information Don. http://www.verticalpower.com/docs/Top_10_Wiring_Mistakes.pdf

 

Pud

 

 

[Methusala]

Just discovered that the EIS instrument takes its info from the charge output rather than the dedicated tach wire. Now have tach readings from both mags. Perhaps one of the CDI boxes is a little sick. Will try substituting another box soon. At last some progress. Only myself to blame, of course! Don