Where should you aim the temp gun to take readings? And if my temp is reporting high but I'm not at peak performance do I just keep leaning?

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Yang

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Where should I aim my IR gun? At the engine case? The cooling fins? The glowplug hole? They're all considerably different.

Sometimes I'm getting readings as high at 220-240F and I heard it should be 200F.

This would seem to indicate my engine is running too lean, however I'm not hitting second gear and I have a nice plume of smoke from the exhaust.

Here is a video of a high speed run from my car. https://streamable.com/n42v0q. I don't think I hear second gear. I'm 1 and 1/4 open on high speed needle

Should I just keep leaning? Or should I not be tuning for top speed runs when this is only the 4th time I've ran the engine (after break in).

I ran a few tanks like I'm driving in the video and at the end the engine was steaming and sizzling a little, which I'm hoping was just built up grime getting vaporized.

One more thing today the temperature is 86F
 
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cbaker65

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Where should I aim my IR gun? At the engine case? The cooling fins? The glowplug hole? They're all considerably different.

Sometimes I'm getting readings as high at 220-240F and I heard it should be 200F.

This would seem to indicate my engine is running too lean, however I'm not hitting second gear and I have a nice plume of smoke from the exhaust.

Here is a video of a high speed run from my car. https://streamable.com/n42v0q. I don't think I hear second gear. I'm 1 and 1/4 open on high speed needle

Should I just keep leaning? Or should I not be tuning for top speed runs when this is only the 4th time I've ran the engine (after break in).

I ran a few tanks like I'm driving in the video and at the end the engine was steaming and sizzling a little, which I'm hoping was just built up grime getting vaporized.

One more thing today the temperature is 86F

If it was sizzling ,then it is hot an if it gives a gurgle sound after you shut it off ,than its definitely too hot!

I point the laser beam right between the glow plug an the fin of the head just as long as it isnt directly
on the glow plug but not in the fin of the head!
But 220 & 240 is not too hot an sounds good at that temp!

Your 2 spd may need to be adjusted a little ,the car in the vid was already pretty fast an the engine
sounded pretty good ,however ,that 1 1/4 turns out seems odd to me an seems to be lean on that
count of turns ,so ,it maybe a little too lean an the 2 spd is not shifting as well an creating the heat.
An engine that is being over revved an not shifting in its 2nd gear will heat up because of the load!

So ,try to back off the set screw adjustment on the second gear about an 1/8 turn ,an richen the
engine up a 1/4 turn an see if that helps ,the goal is to find the shift point an then recheck
your tune & temps!..:thumbs-up::cool:
 
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mzanzirc

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TBH. I don't trust temp guns.

With covid, large companies where I work used expensive FLIR's to measure our temps and most times the readings are as low as 31c or 87f. I must be dead then. 🤣

I have no clue, but I see most people just aim it down to the glow plug.

One other thing I read mentioned here is when the car comes back, the person drops a bit of water on the cooling head and when it sizzles and evaporates quickly, it might be too hot.

Not to highjack your thread, but does any user manual mention measuring them temps of the engine? Or is this just another "thing" people started doing and found it beneficial?
 

Yang

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If it was sizzling ,then it is hot an if it gives a gurgle sound after you shut it off ,than its definitely too hot!

I point the laser beam right between the glow plug an the fin of the head just as long as it isnt directly
on the glow plug but not in the fin of the head!
But 220 & 240 is not too hot an sounds good at that temp!

Your 2 spd may need to be adjusted a little ,the car in the vid was already pretty fast an the engine
sounded pretty good ,however ,that 1 1/4 turns out seems odd to me an seems to be lean on that
count of turns ,so ,it maybe a little too lean an the 2 spd is not shifting as well an creating the heat.
An engine that is being over revved an not shifting in its 2nd gear will heat up because of the load!

So ,try to back off the set screw adjustment on the second gear about an 1/8 turn ,an richen the
engine up a 1/4 turn an see if that helps ,the goal is to find the shift point an then recheck
your tune & temps!..:thumbs-up::cool:
Is there a good guide on how to adjust the second gear screw? I'm not sure what to look for.

Oh and mzanzirc, yes according to this temp gun I am dead too. My body is at 33c
 

TRAT

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I have temp sensors kinda pain but they work.
 

johnnydmd

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Aim down at the glow plug.

Sizzling like that - definitely too lean on the HSN. 1 - 1/4 turns seems far too lean as well. I'd bump that back to 2 or even 2.5 as the manual said, and lean it down between 2.5 and 2.0 turns.
 

gandalfnz

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Dont worry about the temps, start tuning from rich, and when the car runs good and shifts into second, leave it.
Constant temp checks wills stop you from enjoying your new nitro rc.
If you are not above 300F don't worry about it.
 

Yang

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Aim down at the glow plug.

Sizzling like that - definitely too lean on the HSN. 1 - 1/4 turns seems far too lean as well. I'd bump that back to 2 or even 2.5 as the manual said, and lean it down between 2.5 and 2.0 turns.


Isn't that just going to make it run slower? It's already too slow to shift at 1 and 1/4 turns.
 

Yang

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Which one adjusts shift point?
IMG_20220521_074200.jpg
 

cbaker65

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Which one adjusts shift point? View attachment 147061

One set screw would be to hold the hub to the shaft ,that would be real tight an should not be touched ,
an is the screw that would be located in the center inline with the shaft!

The screw that needs to be adjusted will turn easy and is in an offset location next to the screw that is
in the center!.. :thumbs-up:
 

gandalfnz

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I would cover that hole at the bottom of the case, where both spur gears are exposed.
Dont know whow and why came up with such a stupid design, as stones get projected inside, and damage your spur and pinion gear.

Unless I am missing something here?

I just tape over it.
 

johnnydmd

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Isn't that just going to make it run slower? It's already too slow to shift at 1 and 1/4 turns.

You said previously that was where your HSN was, not the shift point. I can't speak about the shift point, not familiar with that transmission.

I'm 1 and 1/4 open on high speed needle
 

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