so i think i blew my hobbit engine :(

metra kitted, stuffy bottom end, hpi, mlm pipe, 4pedal reeds, vm20 running a 30pilot and 170 main. race gears in the rear

was getting closer and closer tuning it perfect and seemed to be running really well, took her out of the neighborhood and it seemed like something was dragging.. like it wasnt really opening up. temps were getting high, i backed off a little to try to get home and let her cool. she was seeing about 430 * F max is what i witnessed :( sigh. she's had plenty of heat cycles and maybe 15 -20 miles on the engine since being build... not a lot of miles but a lot of heat cycles while tuning usually low 300's *F

welp, she made a sound like she wasnt running right then died, the transmission kept the engine turning over until i stopped on the side of the road about 3/4 mile from home. i'll crack into her tomorrow and hopefully figure out what happened... i really havent had luck with the metrakit at all. looking at replacements already (i know i know it's a hobbit and a pita to tune but im patient). Treats has a sale right now for $175 for the malossi 70cc h20 kit (normall 275) but im also eyeing that stage 6 r/t kit.

will update tomorrow/monday with pics and what it looks like happened

Re: so i think i blew my hobbit engine :(

If the engine was turning over you didn't seize it at least. How new was the spark plug?

Re: so i think i blew my hobbit engine :(

Check to make sure your head studs didn't back off.

Common for new builds.

Re: so i think i blew my hobbit engine :(

spark plug was new, i had a few on hand while i was tuning. might have had 2-3 miles on it maybe?

so it was turning over when it shut off but yesterday i tried by hand and nothing. didnt even start pulling it apart, im still just upset with it lol maybe today will be the day. fingers crossed the stuffy crank was worth it and the bottom end is okay, new bearings are probably a definite

Re: so i think i blew my hobbit engine :(

Leak down test. As cheeta said if it turns it was a most a soft seize. If a stud backed out or the nut c racked on one stud which happened to me it will die. A simple compression tester with a drill start will show a leak at the head if u mix up a dilute spray bottle with johsons baby shampoo. Spray liberally but to ascertain if a seal failed or other huge leak elsewhere I block off exhaust, rely on the Reed's to block off intake , inject air at 7 psi via the spark plugs hole. ( I use a harbor freight fourstroke leak down tester in series with my compressor turned down so less than 10.psi (7 is what I shoot for) and see if it tends to hold it without using additional air. Spray the baby shampoo on base gasket etc. If not holding and leak not at base gasket then u are obliged to uncover the seals and then move the blocking the intake proximal from the Reed's to include the entire intake. And yes if the carb - intake isn't sealed you can miss that. Major pain in ass. I have to do this to my red Hobbit that won't start with the treats puch-hobbit head. This week.

Re: so i think i blew my hobbit engine :(

i blew a hobbit once. trying to think of a punch line... got nothing :-(

Re: so i think i blew my hobbit engine :(

If you do switch to another kit the malossi 70cc h20 kit is awesome. My temps stay below 140 and hit mid 50’s mph all day.

Re: so i think i blew my hobbit engine :(

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