Microlighters

Hi all
Could any one of you "slim oukies" that have opened a Rotax 582 on its 150 hours service tell me if it was realy neccesary to do so, and if so what did you find had to be replaced/repaired at this interval?

I would not open the engine. Take the exhaust manifold off and look at the pistons. (Use a bright light) They should be nice and shiney down the sides with no scratches etc. Rotate the piston down and look into the cylinder, again if there are long scratches you have a problem. The inside of the cycinder should have a faint crosshatch type pattern.

Using something that won't scratch the pistons like the back of a screw driver press against the rings. You should get a small movement. I look for oil being pressed out from behind the ring. Look carefully as the ring will have a very small amount of movement.

If your pistons are black on the top and in particular down the sides, especially if the black burn marks extend past your rings then you will need to decoke the engine. Otherwise if all checks out close up, do the rest of the maintenance and fly for another 150 hours

My first 503 only needed decoking at 582 hours. The motor wasn't opened before then.

Now this is my humble opninion. Others might differ. "If it aint broke don't fix it", and "stop fiddeling and fly man" are sayings you will hear quite often here.

Good Reply from Morph,

You can and should also check your carb side, I had a scratch down that end.
Take of your air filters, open your throttle all the way, move your prop slowly to move the piston and see if you have any vertical scratches.

Actually thinking about it I don't know if you can see the piston on a 582 via the intake side, since you have a rotating disc, but I know you can on the 503's.

Regards
Rudi

Thanks Morph and Rudi
Will follow your advice :D If I have to decoke, can I use these decoke sprays availible for outboard motors or do it the hard way?

Decoke spray in my humble opinion only work if you regularly use it i.e every 25 to 50 hours. If you wait too long you are going to have to use some elbow grease to get rid of it.

RudiGreyling wrote:Good Reply from Morph,

You can and should also check your carb side, I had a scratch down that end.
Take of your air filters, open your throttle all the way, move your prop slowly to move the piston and see if you have any vertical scratches.

Actually thinking about it I don't know if you can see the piston on a 582 via the intake side, since you have a rotating disc, but I know you can on the 503's.

Regards
Rudi

You can't......

Dankie Duckie
Try saying that 3 times fast

RudiGreyling wrote:Dankie Duckie
Try saying that 3 times fast

I dust jid :D

Hi guys....

I agree with Morph.... but hell, Part 24 does not allow this -

What to do.... ?

Part what

Morph wrote:My first 503 only needed decoking at 582 hours.

Nah man you got that all wrong - you got to open a 503 at 503 hours - only the 582 is allowed to go to 582 hours.

But on a serious note - part 24 will put an end to common sense.

My 582 did 750 hours before being replaced with a short block. This has now done 250 hours without a hint of a hiccup. The plane gets used 2-3 days a week and no chance for corrosion like you guys down at the coast!

I kill the engine with the choke to lube as prescribed by Rotax.... etc but alas - thanks to the Yanks with all the litigation rubbish we find ourselves in this mess of .... manufacturers specifications!

I agree with you Morph.... if it not broken, don't open it! How many engines have popped after "overhauling" or tinkering?