<span class="Apple-style-span" style="font-family: Verdana, Arial; font-size: 13px; -webkit-border-horizontal-spacing: 1px; -webkit-border-vertical-spacing: 1px; ">I just got a used cen matrix buggy, it is my first nitro rc... well my first rc car. i just replaced a bad servo and got it back up and running again. I was running it today put atankthru it and then i had trouble starting after i filled it up again. I started getting frustrated and noticed that the cab was very loose and could just pull off the engine. i havent seen this happen before and it doesnt seem like it is tightend down by anything it looks like it just slips in, but it is now sloppy... is this right? </span>

Go to Cens website. You can look at the manual online. Probably a small set screw that holds it in.

First of all what nI would do is pull the set screw out along with the roll locks that the screw tightens into, and clean it and inspect it for cracks, or being stripped, then the base of the carb should have 2 o-rings small and thin, and if it doesn't you need to pick up some and your hardware store, slip them on with a little vaseline put your set screw and lock rollers that the screw tightned into, and you should be good if your lock-rolls and set screw is shot then order a new one part #G70369-05 and if you have problems threw Cen go to Nitro RC Hobby, and they'll have it, just click on Cen Parts and keep scrollin until you find the kit.