Break in after rebuild?

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IdriveSlideways

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Does the engine need to broken in again after a rebuild? I'm helping my friend rebuild his engine and all we're doing is replacing the conrod. The piston and sleeve are fine.
 

cbaker65

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Does the engine need to broken in again after a rebuild? I'm helping my friend rebuild his engine and all we're doing is replacing the conrod. The piston and sleeve are fine.

I wouldn't think so ,infact ,after a break-in on a new engine ,people should replace the rod ,
because the rod gets hammered do to the high compression,tight pinch ,an a overerly
eccessive of fuel.

Since the pist/sleeve has already been broke in ,then it shouldn't have to be done again!
 

IdriveSlideways

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Cool. Thanks for the info guys.
 

hotrodrob

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Agreed with all of the above
 

ninnon

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If you replace the sleeve and piston then yes.
 

Certified Mike

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Curious to know if you decided to swap out the rod. How does the new one look compared to the old one?
 

pitbull14218

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It would be cool if you can replace the rod and crank with a stroker setup, is that possible?
 

IdriveSlideways

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Sorry for not replying to this thread sooner but life happened and I had to put the hobby down for a month or so.

So now to explain what's happened thus far.

Literally the day after this thread was posted, my engine spun a conrod bearing and quit. So I tracked down a new conrod from Kyosho specialty website. Unfortunately they didn't have any engine parts on site and had to ordered straight from Kyosho, which took about 3 weeks.

So in the meantime I tore the engine down, cleaned it, and stored it until my new conrod came. It got here today and the engine is back together with good compression and fired right up after 2 rips on the starter. It's running great and moves under its own power as of two hours of this being posted.

The only issue its having is it dies when I brake after a WOT pass. It's launching perfectly and getting up to speed well. If I let off the throttle closes to its neutral possision, it idles down and rolls until I apply the throttle again and keeps going. Only when I hit the brakes and turn in either direction, it bogs and dies.

So that's pretty much the gist of what's happened over the past month until now. Given the current and only issue I'm having, I'm very satisfied with myself for identifying and fixing the problem although it was very apparent to me what had happened to begin with.


23tmws4.jpg

2quun4h.jpg



And this is today after I got it back together.
33u8nlf.jpg
 

cbaker65

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Sorry for not replying to this thread sooner but life happened and I had to put the hobby down for a month or so.

So now to explain what's happened thus far.

Literally the day after this thread was posted, my engine spun a conrod bearing and quit. So I tracked down a new conrod from Kyosho specialty website. Unfortunately they didn't have any engine parts on site and had to ordered straight from Kyosho, which took about 3 weeks.

So in the meantime I tore the engine down, cleaned it, and stored it until my new conrod came. It got here today and the engine is back together with good compression and fired right up after 2 rips on the starter. It's running great and moves under its own power as of two hours of this being posted.

The only issue its having is it dies when I brake after a WOT pass. It's launching perfectly and getting up to speed well. If I let off the throttle closes to its neutral possision, it idles down and rolls until I apply the throttle again and keeps going. Only when I hit the brakes and turn in either direction, it bogs and dies.

So that's pretty much the gist of what's happened over the past month until now. Given the current and only issue I'm having, I'm very satisfied with myself for identifying and fixing the problem although it was very apparent to me what had happened to begin with.


23tmws4.jpg

2quun4h.jpg



And this is today after I got it back together.
33u8nlf.jpg

Awsome ,I'm glad it didn't do more damage!...

We manage to keep are selves occupied waiting for ya!.....LOL
 

SchrodeMode

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The only issue its having is it dies when I brake after a WOT pass. It's launching perfectly and getting up to speed well. If I let off the throttle closes to its neutral possision, it idles down and rolls until I apply the throttle again and keeps going. Only when I hit the brakes and turn in either direction, it bogs and dies.

Does it die every time you hit the brakes or only while braking and turning at the same time?

Have you checked to make sure your carb isn't closing when you brake?
 

IdriveSlideways

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Does it die every time you hit the brakes or only while braking and turning at the same time?

Have you checked to make sure your carb isn't closing when you brake?
Only while braking and turning. Carb stays open when the throttle is at the neutral position.
 

Certified Mike

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I don't want to say this like you haven't researched but... There is supposed to be a gap of about .7-.8mm. If you don't have a feeler guage, a common way to set the gap is to put a 1mm Allen wrench in the throat of the carb and then set the throttle stop. If you have that set properly and you still have the issue, please post back and I'm sure we'll all have some more ideas. Welcome home! :welcome_sign:
 

cbaker65

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That's also what that idle set screw is for ,after your setting ,it doesn't allow the carb barrel to close off
when you let off the throttle or when you brake!...:cool:
 

Certified Mike

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I used the wrong term there... Yes, I was trying to get that. To set the idle set screw on the carb itself, not the linkage. After the carb is set propperly, try it out and see how it goes. I'm guessing that's where the fix lies.
 

SchrodeMode

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Only while braking and turning. Carb stays open when the throttle is at the neutral position.
I don't understand why it wouldn't do it during normal braking, turning shouldn't have an affect on the engine.

Does the carb close when you apply the brakes? It should maintain that ~1mm opening at idle and full brakes.
 

Certified Mike

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The only other things I could think of that might be causing his issues would be if the RX battery was dying or weak and when both servos hit their end points, it's causing fade and glitching.
Or, when it's turning and braking, the fuel is getting sloshed in the tank or somehow missing the pick up and sucking air into the fuel line.
I doubt it's the radio issue but it's possible I suppose.
 

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