revo 2.5 w/ jl .28 max

[darnikuf1]

i have a revo 2.5 with a jl .28 max. I have been running it and noticed it has gotten sluggish. I pulled the carb off and noticed that the carb moves freely. I held the part of the carb that sits in the motor and moved it side to side. it seems that the part that sits in the motor "the bottom of the carb" has a sleeve or something. My ? is, is my carb supposed to move side to side when I give it throttle. it doesn't seem right especially when I give it gas and the throttle arm slips out of the holder to the servo and stays wide open. I'm not sure if its the screw that holds the carb down" I've tried multiple screws and it still moves. any info?

 

[cbaker65]

i have a revo 2.5 with a jl .28 max. I have been running it and noticed it has gotten sluggish. I pulled the carb off and noticed that the carb moves freely. I held the part of the carb that sits in the motor and moved it side to side. it seems that the part that sits in the motor "the bottom of the carb" has a sleeve or something. My ? is, is my carb supposed to move side to side when I give it throttle. it doesn't seem right especially when I give it gas and the throttle arm slips out of the holder to the servo and stays wide open. I'm not sure if its the screw that holds the carb down" I've tried multiple screws and it still moves. any info?

No ,carbs are not to move side to side! They are tightened down by a pinch bolt.
That wedges onto the carb throat.
I heard that sometimes you can put a tiny washer on the pinch bolt nut.
I've had the same issue with acouple of my Ae 28's ....But I solved my problem
a way that most people will snub their nose at!

 

[darnikuf1]

Which is how

 

[cbaker65]

Which is how

I drill a small hole in the block just below the carb, Then I thread a small screw in the hole which acts
as a set screw.
Put carb on ,then run your screw tight into the carb ,but not to were it strips the threads.Loosen screw
back up alittle ,pull carb back off,it should have a mark were the screw left on carb.
Take an drill a small indentation on the carb,but don't drill all the way through.
Get some high heat copper sealant an use around carb throat an your new set screw.
Its bullet proof if done right!
You just need to match up a small drill bit that is slightly smaller than the screw you use & a good
strong steel screw. I use vise grips to bite on the head of the screw to thread the screw into the
aluminum.

 

[Rooky78]

Ingenuitive.

 

[cbaker65]

I thought I had a pic of tha carb mod,but I guess it got erased when I shot photo bucket to the curb.
I can take new pics in detail!

 

[cbaker65]

Ok ,heres a pic,sorry that its fuzzy ,my camera don't like shiney up close metal.
Here it shows where I put the set screw.
If you do this mod, make sure that you drill the hole were it will catch the carb throat as well.
Also ,make sure you put some tissue inside to catch any metal shavings from going in the engine.
You can also by a small tap & die if you prefer to thread hole that way.
But I just always use a good strong harden screw to make my threads in aluminum ,providing
that you have a slightly smaller bid to match the screw.