Need break in help please

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jman214

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I have a sh.28 engine. I let idol for 2 tanks w/ factory setting right out the box. On the 3rd tank, it took forever to start. So I leaned it a little bit gave a little gas and it finally cranked. It is so hard to start. Are there any tips to make it start easier? Every time I give it gas to drive in circles it turns off . I got it to drive one tank but I had to gas it hard why the ignitor was on I just don't want to mess it up
 
Have you tried preheating it with a blow-dryer or heat gun?
 
No I have not what part should I blow the heat on ? Man yesterday hand got blister and shoulder was hurting yeeesh but not going to quit
 
Chances are you only adjusted the HSN (High Speed Needle). The LSN (Low Speed Needle) is what you need to lean to control idle and throttle from a stop.
Read through the following thread. Lots of useful info in there. If it's hard to start due to compression you can also loosen the glow plug just enough to bleed off some pressure. When it starts, tighten it back up. It will save you some blisters. Also, it's the top of the engine you heat up.

https://www.rcnitrotalk.com/forum/threads/nitro-tuning-tips-and-tuning-flow-chart.60832/

Carb.jpg
 
Yea I leaned the hsn but never touched lsn. So I need to Len the lsn cause every time I try to give it gas it dies
 
Read the stuff Rolex posted. Read it 5 or 6 times. I'm serious. A lean LSN will cause a flame out and die on throttle. A rich one will cause a bog and die.The engine stopping tells you very little.

Heat the engine. Liquid fuel doesn't burn. The vapor does. Heating also make the engine loosen up so there is less mechanical binding.
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Make only slight adjustments and do it ONLY when the engine is warmed up. After each adjustment, run it around a little just to clear it. If it is improving, continue to adjust it SLIGHTLY in the same direction and again, run it a little to let it settle in to the new setting. When it idles nicely and gets a good punch off the line you'll know the LSN is set. Be careful that you don't set it too lean or it could cause an overheat. Get a temp gauge just as a safety back up. If you can start it and hit full throttle when it's cold, it's most likely too lean. Allow it to warm up a little before expecting it to perform.
The HSN now needs to be adjusted for WOT (Wide Open Throttle) In the future, you probably won't need to reset the LSN, but the HSN will need regular tweaks for humidity and ambient temps.
 
Read the tuning guide multiple times. And you can try using a hair drier to heat up the cooling head to make it start easier.
 
Also, try lifting it off the ground and leave the heater on, but blip the throttle a few times to try and clear the engine of excess fuel. Don't go WOT, just blip it a few times. Then pull the heater, put it on the ground and ease up the throttle to 1/2-3/4 throttle. Let off, let it coast and before it slows down completely, ease up the throttle again. Just keep doing that and slowing down to turn the truck around the other direction, then ease up the throttle again.

When I break my engines in, I do not let them idle hardly at all as the first 5-6 tanks of an engines life are probably some of the hardest tanks it will see. What your doing is heat cycling the internals and wearing the new parts into each other, which causes alloy grit to run all over in the engine. So, keeping the RPM's up some constantly at least pushes extra fuel/air through the engine to get as much of the filings out the exhaust. I do adjust the HSN/LSN pretty much constantly as it depends on how the engine is responding. If it's so rich that it can't stay running, then your only choice is to lean it out a bit.

Your primary goals are getting the engine up above 200F ( usually doesn't happen until the end of tank two or three) and getting fuel through the engine.

Make sure to shut it down every 5 minutes, put the piston at BDC and let it cool to about 80F, then fire it up again and repeat. By the time you get to tank 6 or 7, it should be loosening up quite a bit and you can start leaning it out some to get it running better.

I've broken in at least 20 engines, probably more over the past 15 years. That would include 2 SH 28's. The only ones I've had issues with were traxxas engines, but I think that's due to me expecting too much out of them. The 2.5R in my jato broke in and runs just fine. But my 2.5 maxx and 3.3 revo, they just didn't give me the power I wanted and I beat the crap out of them.
 
Is there a place I can mail the car so they can break it in? My knuckles are beat to death. I leaned out the lsn and no luck . Redcat keeps telling me don't touch the hsn leave it rich. I went to hobbytown USA no help from them cause it was redcat. I knew I should have got a revo so they could help but I might just take a loss and sell it dirt cheap so I can take
that money to buy a revo so they can help with the car.
 
Lol.....I usually lean mine out allitle an also loosen glo plug when I get it started ,then remove
igniter an tighten glo plug while its still running.
Like olds97 says ,you can not let the engine idle an load up with fuel ,it will simply die
when you try to throttle.
 
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Mail me the engine. Worse that can happen is that I get into it and find out it's dead/damaged or something. Might take a few weeks for the weather to cooperate though. You'd have to cover shipping both directions... and maybe a few bucks for the half gallon of fuel it would take... if I can get it running.

I hate the thought of a newbie giving up and going brushless. ;)
 
Ok thanks will try in the morning knuckles are sore right now. So I should lean out the lsn a bit more I did it a little I just don't want to hurt anything. Because it's still a lot of smoke and fuel coming out so basically I should be hitting the throttle to keep it from shutting off.
 
Thank you guys so much I stopped being scary and leaned out the hsn and kept hitting the throttle to clear it out . I had to lean it a whole turn and bam it idles good does not cut out stays running I'm so happy now. I finally understand the difference from the hsn and lsn. Will finished breaking in tonight
 
Me to man I'm hooked now still thinking about a revo or losi 8ight which is the better one ? I have a lil extra cash to burn from some money I saved on new exhaust for my mustang.
 
That's great news! The SH engines weren't ever too bad to break-in from what I remember. Didn't take nearly as much fuel before it settled down and put out good power as my LRP's did.

Keep us posted as to how it goes. I haven't had an SH engine in a long time.
 
Mustang? Did he say Mustang.... you have my undivided. Lol
 
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