Fuel Foaming
 

For years, I've been told that vibration/fuel foaming is the cause of so many of our engine troubles. I have always tried to mount and isolate my tanks so they would not foam. I have a plane with a OS 91FX in it. I wanted the larges tank I could get in it, (I like long flights) so I squeezed the largest tank in it I could. It is agains the floor, sides and top, no foam. I've been flying the plane for 6 months now and not one problem. It idles great, almost unlimited vertical, will fly all day inverted and never a dead stick. I have well over 100 flights on it. Yesterday while shooting touch and go's, I loosened the battery. I took the wing off to retie the battery down, this I did. I started the engine with the wing off to check the battery tie down for vibration, I noticed the fuel was foaming so bad it looked white instead of pink. I held the fuse vert, horz, inverted and shook the dickens out of it, the engine never missed a beat. Replaced the wing and flew three more flights no problems. My question is, is foaming the engine demon we make it out to be. I will continue to try to pad and isolate my tanks. I would like some thoughts from you guys about what I just described. Thanks.

Fuel Foaming
 

You are probably getting foaming on the top, but the clunk is still in the bottom where the fuel is not foaming bad. I have seen it foam so bad that all you get is air in the lines, and other times, you get a lot of faom, but no air in the line. Depends on the tank. You may just have enough fuel left to keep the clunk in it all the time. If you run it really low, you may run into a leaner run problem. Just my thoughts

Fuel Foaming
 

Add 3 drops of Armorall to a gallon of glo...stops foaming...

Fuel Foaming
 

I think his point was, he has no problems at idle, in the air, inverted, or for long duration, so why should he add anything.

I, too, have noticed a lot of foam in various tanks, with good performing engines. I add nothing.

Good post, this should generate some discussion.
Dave Olson

Fuel Foaming
 

I have never heard of this. Is that the armorall you use to clean your car? It really works?

Fuel Foaming
 

Some motors are more sensitive foaming than others.....and it realy only takes one time for the "pride and joy" to go back to kit form...

It was just a suggestion...

Fuel foaming
 

Yup,
I had read about it here before...
I didn't believe it either, till one of the club members had a profile something....could not stop the fuel from foaming and engine going lean in the air...

Said something about it to him.....he broke out the Armorall (the kind that you clean you'r car with) put a short spray in the fuel jug, shook it up...refilled the tank....nary a problem after that...

It's supposedly the silicone in the Armorall that stops it from foaming..

Aint" science wonderful.... :D

Fuel Foaming
 

Geez, I will have to remember that. I haven't had a foaming problem for a long time, but seems like there is always someone that does. Thanks. I will mention it and see what happens.

Amazing what you can learn on here eh!

Fuel Foaming
 

Me either...gas don't foam. :)