Spark plugs for a Rotax 503

[Thechap]

I am using the recommended spark plugs for my inverted Rotax 503. Is it okay to go to a one size "Hotter" plug.

Thanks,

Bryan

[Penguin]

Why do you want to use a higher heat range plug?

[Thechap]

I was told it would help with the issues of no start since the engine is inverted. Helps to burn off the excess gas and oil.

[Jamie Cleary]

Bryan,
One heat range probably wouldn't hurt anything but I would make sure
everything else is up to par first, usually when an inverted engine gets
hard to start it is either low compression or weak spark, if it is an old
points engine I would suspect points. If you do try a hotter plug I would
pull it after a short flight and make sure it isn't lean and keep an eye on
your EGTs.

[scandtours]

Better clean the plugs before flight, especially if engine stays in hangar for a longer period of time.
You are right, in an inverted engine the oil will drain down into spark plugs and it will make it impossible to start it no matter what kind of sparks you are using. The oil covers completely the electrons.

[GyroRon]

Hotter plug won't help the starting issue. Stick with the reccomended plugs. If your tired of how hard it is to start, flip the engine rightside up.

[SideKick]

Bryan, You may have a carb adjustment issue or something else. I just pulled mine out of the garage for the first time since Larry's Flyin and it fired on the first pull and started on the second pull. I would be afraid with a hotter plug you could run the risk of burning a hole in the crown of your pistons.

[rickloon]

RE inverted rotax , if you have lots of troubles starting after sitting just remove your "flying" plugs and put in some older ones , then switch back befor flying again. No worries of to hot a plug, no oil fouling. Just be sure your jetting is correct for your aircraft and alt.

[Rehan K.Janjua]

Hello

Is it easy to start with cleaned dry plugs? ......if yes......

Use recomanded plugs. NGK BPR8ES. Aircraft type only.
Hotter plugs will not solve the problem.

Oil gets there when the engine is OFF.
Oil injection seepage is more compared to pre mix.

Move the right side up.
Before storage, remove one plug from each cylinder and stick
some rag to keep the dust out and absorb oil.
Keep 2 sets of plugs.
Use clean dry flying plugs and rotate plug removal every time.

Good luck.
Rehan

[phantom]

on one of my twin engine gyros the bottom engine had this problem in cold weather and I used br8eya plugs to fix the problem until I tilted the mount 30 degrees so the plugs were not the low point of the cylinder.

Norm