Joe Handley Posted July 23, 2009 Share Posted July 23, 2009 Had a customer bring in a 3.3 Revo that had just been tuned by another area hobby shop and it quit shortly after he got the truck home and started driving it For some reason the piston got stuck half way up the sleeve on the compression stroke (Dad thinks it was run HOT sometime very recently, most likely by the guy who "tuned" it for this customer) and the crank and rod kept going. The rod split length wise in two after getting shoved into the wrist pin and continued it's path through the top of the piston before the rod and crank finally stopped just short of the head and plug! Quote Link to comment Share on other sites More sharing options...
dwc43 Posted July 23, 2009 Share Posted July 23, 2009 Wow. So that's the pic that did not show up in that e mail you sent me last night. Never seen a rod split like that before. I guess anything can happen at 40,000 rpm. Quote Link to comment Share on other sites More sharing options...
Joe Handley Posted July 23, 2009 Author Share Posted July 23, 2009 Yup, I resent the pic tonight too David, I think the crank finally stopped turning when the big end of the rod got near the wrist pin. Quote Link to comment Share on other sites More sharing options...
dwc43 Posted July 23, 2009 Share Posted July 23, 2009 Yup, I resent the pic tonight too David, I think the crank finally stopped turning when the big end of the rod got near the wrist pin. That would do it. Or it just locked up from the heat. You should find black on the parts if it's heat related. I spun a 3 and 4 rod bearings on a 323 race engine one night at 68 to 7200. It was an oiling issue. That's when we started feeding the crank from both ends. The rods were black from the heat and lack of oil. Quote Link to comment Share on other sites More sharing options...
Joe Handley Posted July 23, 2009 Author Share Posted July 23, 2009 We never pulled the motor apart, the guy is probably going to exchange it for a new 3.3 Quote Link to comment Share on other sites More sharing options...
steve_b Posted July 24, 2009 Share Posted July 24, 2009 I actually have seen that before...couple time.... on a boat when it capsized at full throttle and hydrolocked, if tore it up exactly like that. but, that really looks like a lean burn seizure....(but, it sounds sooooo cool when they bumblebee out like that) *sigh* hope they don't let the same person tune the next one Quote Link to comment Share on other sites More sharing options...
cruz Posted July 24, 2009 Share Posted July 24, 2009 Wouldn't you get better responses to your question if you go to an RC website? I am not being rude or anything and I am sure you have a handful of guys that like RC here but the question just doesn't fit quite right in this forum..... Quote Link to comment Share on other sites More sharing options...
Joe Handley Posted July 24, 2009 Author Share Posted July 24, 2009 I actually have seen that before...couple time.... on a boat when it capsized at full throttle and hydrolocked, if tore it up exactly like that. but, that really looks like a lean burn seizure....(but, it sounds sooooo cool when they bumblebee out like that) *sigh* hope they don't let the same person tune the next one Apparently this one sounded a bit like a V-Twin when he fired it for the first time after getting it back from this shop. The guy who ran that shop called the one I work for asking if the guy was telling the truth because he was trying to get a new engine for his truck from this shop because of this. Sounded like from now on he will be shopping with my store from here out for his hobby needs. Wouldn't you get better responses to your question if you go to an RC website? I am not being rude or anything and I am sure you have a handful of guys that like RC here but the question just doesn't fit quite right in this forum..... I was just showing a carnage pic here, figured that even though it was RC related, there might be a few good stories in 1:1 and smaller scales that would match this pic Quote Link to comment Share on other sites More sharing options...
Joe Handley Posted July 24, 2009 Author Share Posted July 24, 2009 I dabble in a little R/C, as does Gregg, and, I'm sure, others who post here, so the occasional R/C post does not offend me in the least, so long as it doesn't get out of hand. Joe, if you wanted to see a totally fried motor, you should've seen the Traxxas 2.5 the guy brought into the shop where I work awhile back. It was in a vehicle a guy had bought off a kid for $50, and the kid had completely disregarded the break-in procedure. That thing was toast! We've had a few engines come in like that, especially the early 2.5's, but this it the first one I've seen where the rod actually split on the wrist pin and punched through the top of the piston. Quote Link to comment Share on other sites More sharing options...
v8horsepowercj Posted July 24, 2009 Share Posted July 24, 2009 Looks like the guy tuning really knew what he was doing I have a traxxas Jato with the 3.3 in it I run it on 30% and with a slightly rich ( safe ) tuneup it makes so much power you can't keep the front end on the ground. I can't for the life of me figure out why somone would spend that kind of cash on an RC and disregard the break in and tuning instructions????? But hey he did provide the customer with a really nice wrist pin inspection port (HOLE) LOL Chris Quote Link to comment Share on other sites More sharing options...
nitrojunkie Posted July 24, 2009 Share Posted July 24, 2009 I dabble in RC cars and Helicopters a little bit.Now I am no expert tuner by any means but the general rule of thumb is you should always see a trail of smoke when running any nitroengine in an rc vehicle.My question is and not meant to take business from a hobby shop,Why do these people buy these cars and trucks and not learn how to work on them or tune them themselves? They're not that complex and they are very well built and can from my experience take a fairly good beating.Are they scared or do they just have so much money that they just don't care? My R/C stable consists of an HPI RS42 an HPI Savage 25 this actually is my sons and my Thunder Tiger Raptor 30v2 with OS 37 ringed engine.I can't afford a topfuel car so this is how I get my nitro fix! Quote Link to comment Share on other sites More sharing options...
Joe Handley Posted July 27, 2009 Author Share Posted July 27, 2009 I've seen the 1/16 Traxxas stuff run and would love to get my mits on one of the Mini-E-Revo's but I've been working on getting my Losi Comp Crawler running and my Axial AX10 that I was competing with swapped over onto a SCX10 chassis, so what little money I've had to spend lately are going into those. I ran the LCC at the SCRC comp at Illinois State Beach Park in Zion, IL a couple weeks back and tied with another LCC owner for 4th place. Amazing part was both trucks were being run in their first comps, on a difficult course (sand and rock not dirt or clay) that neither one of us (as well as about 90% of the competitors there) ever ran before. Here's the two trucks; Here's the Axial, it's eventually going to be getting one of the HPI Wrangler Rubicon bodies And here's an early pic of the Losi, I've since swapped over to Losi's Rock Carver Tires with memory foams up front and added about 17oz of weights to the rims (10 up front and 7 out back) and a Trinity Monster Maxx 21t 550 motor. Quote Link to comment Share on other sites More sharing options...
Art Anderson Posted July 27, 2009 Share Posted July 27, 2009 Gee, And I can look across this room at a gorgeous Dumas 1930 Chris-Craft dual cockpit inboard runabout that has yet to see th water, almost 20 yrs after it was built for me by a customer of my then-hobby shop! My nephew cut scale planking from Honduran Mahogany to replace the cheap Phillipine luan sheeting Dumas packed in the kit, dual water cooled Mabuchi 540's, an electronic speed control. Hmmmm! Do I hear the park lagoon calling me? Wonder how this thing would be chasing ducks? Art Quote Link to comment Share on other sites More sharing options...
Ron L Posted July 28, 2009 Share Posted July 28, 2009 The most damage I've seen (since I don't own a store) is when my friend ran his 2-speed .12 HPI outside the hangar at work for hours on end and the rod exploded into a few pieces, but they all stayed inside the engine. I've never seen R/C tires that bald before, either. We beat the ###### out of that car. i never got into the "gas" side of R/C but i'm becoming more and more interested in it. i've only ever had electric trucks and buggies and had alot of fun with them, but since the problems i've been having with my current truck i'm looking more and more into the gas stuff. Dave Ken, i have a Tamiya Super Clod Buster and i think my real issue is the batteries i have and the mechanical speed control. i have an electronic speed control but never installed it. the truck is "box stock" but has ball bearings and i asked not long ago about my run times which to me seemed awfully short, not more than 5-7 minutes typically. i hear that's about right though with the Clod Buster Dave I went backwards. Always into gas everything as I thought electric was for chumps. Well I got an electric aircraft a few years ago and I was sold! The battery and motor technology these days is just amazing compared to what was available when I first started doing R/C in the 80s. Many motor/ESC combos from even just 5 years ago are considered obsolete. Your Clod with a brushless ESC and LiPo battery (3000mAh+) could easily meet or surpass the run times of many gas cars. Electrics also have close to 100% torque as soon as you hit the "gas" which makes them feel faster than the "peaky" power you get from nitro engines. I've got a 1/18 scale Associated RC18r and 1/18 Duratrax Vendetta and they're the most fun I've had with R/C off-road in years. With just two batteries I have enough juice to run them until I'm sick of it, sometimes not even running the battery down completely. I sure don't miss my fill bottle, glow plug starter, starter box, "starting module" for electric-start nitro engines, slime all over the chassis... Search Youtube for brushless motors. There are some insanely fast electric cars out there, some beyond the realm of being controllable. Quote Link to comment Share on other sites More sharing options...
nitrojunkie Posted July 29, 2009 Share Posted July 29, 2009 Gee, And I can look across this room at a gorgeous Dumas 1930 Chris-Craft dual cockpit inboard runabout that has yet to see th water, almost 20 yrs after it was built for me by a customer of my then-hobby shop! My nephew cut scale planking from Honduran Mahogany to replace the cheap Phillipine luan sheeting Dumas packed in the kit, dual water cooled Mabuchi 540's, an electronic speed control. Hmmmm! Do I hear the park lagoon calling me? Wonder how this thing would be chasing ducks? Art Yeah I got the 55 Cobra had it about 12 years still not finished gonna be a pretty boat one day. Quote Link to comment Share on other sites More sharing options...
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