New spark plugs - spark plugs often fouled.

Another solution could be the REM37BY

Any experience with the REM37BY or a Tempest similar solution?

Yes, as posted on EuroGA in similar threads before, REM37BYs were introduced years ago to solve problems with lead fouling on O-235s, and are useable on many other four cylinder Lycomings as per the Champion application chart. They work well in my O-320, I’ve never had a fouled plug with them and I see no reason to use anything else. Price is similar to standard plugs. I haven’t used the Tempest version because I haven’t needed to replace my Champions but might do so when the time comes.

Ben,
these plugs are very clean after 150 hours. They actually had almost zero deposits and for sure they were not wet. They also have exactly the color they should have. As I said, i lean aggessively and fly LOP almost always (95 Percent). Engine has a compression of 73-75 on all cylinders with 1000 hours TT

REM37BY

We use these and they still foul. But not when I fly it and lean it like no tomorrow.

REM37BY We use these and they still foul. But not when I fly it and lean it like no tomorrow.

If that were mine and if they were lead fouling on the ground (the normal situation), I’d try leaning out the idle mixture. I do lean mine with the lever on the ground, but not to a manic level, and have had no lead fouling problems with REM37BYs.

I believe I noticed they’re not approved for all the engines they would appear to suit based on cylinder type etc, and (again IIRC) not approved on any angle valve engines.

Flyer 59

Enclosed is a table showing foiled plugs. I would think that yours are the bottom 2.

Also look at this

No, they are not. Believe me, after dealing with engines for 30+ years I know when a spark plug looks good. The picture might be a bit too dark, but they were all between light gray and light brown and dry.

I improved the exposure (of the dark parts) a bit for you.

Alex_ wrote:

I have read about people leaning for taxi but always been unsure about this.

I always lean aggressively for taxi. You do need something to remind you to set the mixture for take-off before you … take-off.

Archie wrote:

You do need something to remind you to set the mixture for take-off before you … take-off.

Yes, a dying engine on full power reminds you to adjust the mixture. When you lean the mixture to peak in near idle conditions, the engine will not run with full throttle so there is very little danger.

Exactly. I wonder why so many pilots don’t understand that! The way i lean for taxi the engine would immediately stop if i applied power.

Also i always put my hand over both levers for t. o. and push them fwd together