BROKE STAB

My Feedback: (4)

Okay I have a really nice Saito 72 that runs greatinverted,upright,knife edge, right up until you pull it in a hover then sometimes she does good and some times she dies.
The tank is mounted outside of the fuse on a sledge 540.It has caused me to replace to sets of landing gear and a tore-up plane.
I really do not want to put this in my new EF EDGE 540T until I can solve this problem.

Thanks in advance for any help, Daniel

AllTheGoodNamesAreTaken

My Feedback: (180)

Sounds too lean to me. With about a 1/4 tank, hold the plane level then upright. The RPM should increase slightly.

jsn

My Feedback: (8)

If it's not lean then check your tank clunk line... if the line is a tiny bit to long it can close off clunk on the back of the tank and kill the fuel supply.

John

BROKE STAB

My Feedback: (4)

Both good ideas guys. I will try both of them today.
Also I was reading that I might need a updated back plate for the engine.
Anyone have any thoughts on this?

w8ye

My Feedback: (16)

See if you can pull your intake manifold in and where it goes into the head.

If you can wiggle it, you are a candidate for a new backplate

http://www.horizonhobby.com/Products...rodID=SAI7217A

http://www.horizonhobby.com/Products...rodID=SAI8091B

shred_man

Hi,

I'm in work on a hangar 9 twist also powerd with a FA-72. Hope that I will not get your problem during hovers. I will try verticals in a save altitude. How about the new backplate, what is different ?

Regards
Frank

w8ye

My Feedback: (16)

The new back plate is reinforced under the carb mounting platform on both sides of the top left backplate hold down bolt.

BROKE STAB

My Feedback: (4)

Put the new back plate on and man what a difference.This thing really made a difference in this engine.
Yes it was leaning out when pulling vertical.Richened it up and changed the back plate and what a difference.
The o-ring seems okay and has a tight fit but I will get one coming anyway.

shred_man

How can I identify if I have a new back plate on my saito engine? I ordered the engine on Feb. 2006. Maybe it has the new reinforced back plate?

w8ye

My Feedback: (16)

The old backplate has no braces under the lip for mounting the carburetor.

The new back plate has one on each side of the upper left backplate to engine mounting screws.

See the following pictures. If you look closely, you can see a brace under the mounting pad.

The last picture shows the old back plate but you have to look closely

BROKE STAB

My Feedback: (4)

Seems to be running good .
Just got in the EF Edge and I am working hard to have everything ready for this weekend.
Found a problem with the plane but really no biggie can easily be fixed.But that is for another thread.
Thanks guys for all the help and I will let you knnow how it goes.

BROKE STAB

My Feedback: (4)

Just wanted you guys to know that the mods worked out great.The new back plate has seemed to take care of the leaning out problem.
Also saved a guy at the LHS from giving up on his 72 with the same problem.

William Robison

My Feedback: (3)

Here are pictures taken at an angle that shows the difference.

First is the old style, then the new, finally a shot showing how the added ribs support the carb.

Bill.

William Robison

My Feedback: (3)

Shred:

An FA-72 sold this year (2006) should have the later back plate. If it does not fuss at your supplier, he may well send you one at no cost. The late style has been in production about two years, if yours has the old one it was old stock at the dealer's shop.

Bill.