Flanker

Hi, I've been out of the nitro scene for a good few years but I bought my 14 year old a Hyper 7 V2 for Christmas as I still had some parts from my Hyper 7 from 10+ years ago.
Now it has the .21 turbo head, we put it through the standard break in procedure with no real issues and now we've leaned the HSN a fraction of a turn (factory settings were extremely rich).

The issue is when we finally took it to the track last week, it starts, idles fine, but as soon as it does 1 lap it dies... The engine is not getting very hot, and I've tried 3 different glowplugs.
The old pinch test seems to be ok as well indicating the engine is not to lean or rich.

Really pulling my hair out as my kid is losing interest and this problem is proving to be hard to diagnose. It happens almost every time, . Start the car, put the shell on, drive it around, it dies.


The only think I can think of is the fuel is a bit old and it was from my model plane (so about 10% nitro). Before I go for a 1+ hour drive to the LHS (that sells glow fuel) could it be a fuel problem?

OutLore

iTrader: (1)

When you say the fuel is a bit old - how old? And 10% might not cut it. Definitely worth the drive IMO to the store for fresh fuel.

Also if it's not getting hot it may just be running too rich?

NitroVein

Airplane fuel usually has very high oil percentage, that doesn't work.
That it might be old and has to low nitro percentage isn't helping either.

BrakeTurnAccelerate

iTrader: (40)

Get new fuel. Airplane fuel has extra oil, as the engines tend to stay at higher RPM's for prolonged periods of time. The extra oil, coupled with 10% nitro will result in a really poor burning fuel in a car engine.

Flanker

Ok, I'll try and grab some next weekend. The 2 other hobbyshops within 20m of my place don't sell glow fuel anymore

Pugg

order some online. probably cheaper anyway

Matt Piva

iTrader: (25)

If your interested in getting your son into this for fun i recommend you look into getting some better quality stuff. As time goes on those little issues become bigger especially with an engine not running right coupled with an inexperienced driver. Getting a good second hand car could be the best investment for your son so he can go to the track with a current rig that's easy to work on and runs. Your buggy is a rtr from really old times, even when new those engines and the car over all weren't refined in any way and failed if you weren't on top of anything. Since you seem new I can tell you Losi has overall great support on here in the forsale threads along with in hobby shops and ppl won't hesitate to help u when they see a current buggy. I have a new 2.0 I could sell u cheap, probably half of what u paid for your 7. N those deals are on here all day everyday.

By the way your fuel is a big issue but if your engine is cutting out once it goes 30 seconds it's probably the temperature of your plug, get something really hot and make sure it's correct for your engine. Most engines work with a plug that sits at the correct depth inside the head button and I would suspect this is your issue. It may be hard finding a reliable recommendation for that engines plug choice but I'm sure it's somewhere. Get yourself some 20-30% nitro fuel and plugs and new line if it's old.

ozziii

Hey Flanker, I see you're in Australia, not sure where you are but you can get NEO+ 25% (10% oil) online, delivered from the factory in SA, its a great fuel & made here as well, every major event in Australia has been won using it, 8 litres minimum though, but only around $120 or so delivered to your door which is pretty good.
NEO+ 25% 8 Litres (2 x 4 litre)

Also, the Hyper 7's may be old buggies but they are still a decent & strong buggy, great for beginners to learn with, (I had the Hyper PCR & it went great) & depending on the engine, some of them can be reasonably good as well when tuned correctly. Some people like to push their fave brand but just stick with what you have for now & when you want to upgrade then look into a something then.

TheNitroGuru

Hey, I know this was already mentioned but want to touch base on this. It absolutely sounds like your plug isn't keeping the engine at running temps, get a hot plug and see if that does the trick. If not, next step if changing out that fuel, get it all out of the carb and engine. If no luck, I'm curious to see what the temps are around you and if you're preheating the engine, not just idling it. Give it a good preheat to ~200, fire it up with the fresh plug and fuel.

mercfocus

iTrader: (3)

Totally it's the fuel. You broke in the engine using that same stuff? That in itself is probably not a bad thing. Extra oil and low nitro is required by some engine makers but there's no way anybody can expect a buggy engine to run very good on airplane fuel.

When you get the right stuff, I'd do a couple more break-in tanks just cruising in a parking lot first and then get onto the tuning. BTW, your tuning's going to be way off.