Rex P5 help?
so, i bought a Ofna Dominator off a guy i work with, got a good deal on it, and instead of whatever the truck was supposed to have in it, the guy had a Rex P5 engine in it, he had it running when i bought it, but it wasnt running right. its been a while...15-20 years since i've messed with nitro engines, however, i've been an auto mechanic for 10 years, and had a couple of second jobs working in bike shops, dirtbikes and the like. the carb on this thing is trashed, at one point or another, someone has jammed the slide needle down into the spraybar (aka emulsion tube in dirtbike/atv lingo) at certain parts of adjustment on the needles, the slide catches, and wont open up, and i'm tired of trying to d*^% with it. also, the crankshaft seal/bearing assembly is leaking, is this as much of an issue on nitro engines as it is on a 2 stroke gas engine? a crank seal leaking on a gas engine will wreak havoc on trying to get something to run right. is there anywhere in the US that i can get Rex engine parts, such as a complete carb, and some engine seals?
next question, is there any way to determine what state the compression of this engine is? i may not even want to spend any $ on it if its wore out, or close to it. i tore it down, and right at the top of the piston travel in the cylinder, it gets tight, so tight it wont move any farther up the cylinder, is this a good sign or a bad sign? with it assembled, i could feel the compression as i turned it over by hand, but im not sure what it should be.
and finally, if i find out that its gonna cost me $150-200 to get this engine right, i doubt i'll go that route, one of the engine mount tabs on this crankcase is broken, so theres only 3 bolts holding it down. anyone care to give me some opinions on what else i could put in this dominator to get it moving? im not looking for a race engine, i want ease of tuning, and reliability.
by the way, when i pulled the sleeve and piston out, the top of the cylinder, and top of piston was a nice light golden brown, if color is any indication of anything. i put the glow battery on the plug with the head off, and checked it, all but about 3/4 of the very bottom coil was glowing almost white hot, is the last 3/4 of a coil not lighting up a bad thing?
Last edited by dingo1799; 04-25-2006 at 08:16 PM.