California Help Tuning Engine in San Diego

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alot closer, id try for a bit tighter of a mesh though. yes it does get very frustrating. but in the end it will save tons of pains doing it again and again by getting it set correct before running it. first rig i got went through 3 or 4 spurs before i was able to get meshes set up correctly.
just remember the most surface area is the middle of the tooth for contact. thats ideally where you want it to be at but that would cause binding, so you want it to be as close to that as possible. even for a practice just to see where everything lines up id set it up a bit tight to see where the contact is then just back it up from there.
 
alot closer, id try for a bit tighter of a mesh though. yes it does get very frustrating. but in the end it will save tons of pains doing it again and again by getting it set correct before running it. first rig i got went through 3 or 4 spurs before i was able to get meshes set up correctly.
just remember the most surface area is the middle of the tooth for contact. thats ideally where you want it to be at but that would cause binding, so you want it to be as close to that as possible. even for a practice just to see where everything lines up id set it up a bit tight to see where the contact is then just back it up from there.
while holding the spur gear still with one finger/hand try to rock the clutchbell back and forth, you should barely be able to rock it back and forth, barely enough to see but enough where you can kind of feel it almost instantly click over contact with the tooth on the other side.
 
I think this is the best I can get it:
 

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that looks good! just to be safe in the long run id also plan on getting a few more spurs, between mesh settings being weird and just weird torque situations, and bolts loosening, its pretty handy to have them on hand! hope you get er running soon!
 
@D3MON I bought three sets! Haha, you read my mind.

I got the engine running:


This LNS seems too lean right? That's what the purring is?
 
@D3MON I bought three sets! Haha, you read my mind.

I got the engine running:


This LNS seems too lean right? That's what the purring is?
Try pinching your fuel line as close to the carb as you can, if it does right away or takes less than 3-5 seconds to die it's to lean, if it takes longer than that its rich
 
It was shutting off at 1z2 secs. I turned out the lower end 1/4 and it helped a little. I guess I'm really off. Will have to go back tomorrow!
 
@D3MON: this is my idle now:


I have good WOT and good acceleration/response. However, after a WOD, engine dies when I hit the brakes. Recommendation? Should I lean out the bottom end? Or just adjust the idle screw (I'm at .5 mm, measured with a pin gauge)?

I'm actually confused as of when I should use the idle screw intead of the LSN. Can you explain scenarios when I would use the idle screw?
 
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@D3MON: this is my idle now:


I have good WOT and good acceleration/response. However, after a WOD, engine dies when I hit the brakes. Recommendation? Should I lean out the bottom end? Or just adjust the idle screw (I'm at .5 mm, measured with a pin gauge)?

I'm actually confused as of when I should use the idle screw I stead of the lsn. Can you explain scenarios when I would use the idle screw?
depending on the pinch test, usually when my truck is sounding like that, my LSN is really rich and my idle is a bit too closed, gives a false high idle scenario, Before anything make sure that your controller trim is set, when you break it should not close the carb any further than if your controller is in idle position.


as far as an explanation, on the needles (bear with me i suck at explaining this) i more or less look at it as a garden hose, with 3 spigots, the end spigot is your idle, second spigot up is your LSN, and spigot closest to the source is your HSN, if either or both of the first two are too far closed you will not heavy a steady stream to the end, it will just be a trickle or nothing.
now when the first two spigots are open to far (LSN/HSN) there is a lot of pressure blowing by the final spigot. think of it as holding your thumb over the end of the hose covering it part way. That's what makes it be a too rich scenario.
now your throttle is like opening up the middle spigot from right above idle to about 50(ish)% throttle (2nd spigot fully open), then from 50%-100% that is opening the first spigot closest to the source.

setting the needles adjusts how far closed the spigots are allowed to be in idle position and not allow them to close any more.
this is the reason you do not want to set it with your throttle trim.

all the needles affect each other slightly, but when the other settings are correct, idle should only affect idle, the LSN to rich will affect it because it is too far open at idle position and let fuel blow by when in reality it shouldn't be allowing so much fuel to pass through.

long winded as hell sorry, hope someone can elaborate more if needed or i missed something.
 
@D3MON it sounds like you believe I should increase my throttle carb gap? I'm at 0.5mm. Should I increase to 1.0 and reset LSN. I opened up the gap yesterday and my idle RPMs increase significantly.
 
@D3MON it sounds like you believe I should increase my throttle carb gap? I'm at 0.5mm. Should I increase to 1.0 and reset LSN. I opened up the gap yesterday and my idle RPMs increase significantly.
how is your pinch test of the fuel line? is it still in the 3-5 second area? if so i would open it (Idle) up a bit slightly.
you did double check your throttle trim right? the controller should not be able to close the carb any further than when it is at idle.
if its longer than the 3-5 seconds, slowly lean the LSN 1/8 turn til it does,
I'm wondering if your HSN is still a bit rich, to where your engine is loading with fuel so when you let off it rich bogs and dies. how is your HSN? good temps and good response? getting the nitro scream when revving high?
 
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@D3MON Pinch test is at 3 seconds, I also checked the trim and it seems fine.

You bring up a good point about the HSN. It sounds good, and performs good. I need to check the temperature to see how hot it's getting. It might be too rich. I doubt it, but I didn't think it could bog due to rich HSN when idling. I thought it would only bog when accelerating due to a rich HSN.
 
It won't necessarily bog at idle from a rich setting on the HSN but during that WOT pass if its pouring too much fuel in when you let off all the extra fuel built up in the crankcase is still pouring through so the drop to idle is still going to be rich from that WOT period. Until that excess fuel burns off and settles back to idle.
 
@D3MON : Sorry, that's exactly what I meant. I meant that a rich HSN could bog an engine after a going straight from a WOP run to idle. Which seems to be my case. However, if I like the performance of my HSN, can I just modify (open the carb gap? Sorry I have all these questions, I haven't been able to find anyone I can ask in person
 
@D3MON : Sorry, that's exactly what I meant. I meant that a rich HSN could bog an engine after a going straight from a WOP run to idle. Which seems to be my case. However, if I like the performance of my HSN, can I just modify (open the carb gap? Sorry I have all these questions, I haven't been able to find anyone I can ask in person
Yes if the HSN is set right it's most likely other areas, LSN/idle. In your case I'd expect idle so I'd adjust that slowly and see if it gets to your liking.
 
@D3MON I adjusted the idle set screw. The idle gap was depending on the throtle arm/angle from the carb position. I adjusted the set screw so that no matter hat andlge the carb is position, it wont shut close. IT will always remain t he same because now I am using the set screw. Engine is running, thanks!

Now I have another issue! Remember the 3-speed transmission? It's acting up. If I revv up from stand still it barely crawls....if I do very small throlle it craws faster...once I get it to craw I can use the second gear slightly...and if I open up the throlle after the third gear runs perfectly!

Here are my thoughts:

1. Mesh is messed up? Too tight on first gear? If this would be the case, the gear should spin? Correct? All gears spin. I pick up the truck and run the engine and no issue, all gears spin.

2. Second gear is overwritting the first? Meaning it is coming in too early? This can be adjusted. Can this actually happen though? Second gear kicking in before first? Causing the engine to skip first gear? Causing it to barely move because RPMs are too low for 2nd gear?
 
@D3MON I adjusted the idle set screw. The idle gap was depending on the throtle arm/angle from the carb position. I adjusted the set screw so that no matter hat andlge the carb is position, it wont shut close. IT will always remain t he same because now I am using the set screw. Engine is running, thanks!

Now I have another issue! Remember the 3-speed transmission? It's acting up. If I revv up from stand still it barely crawls....if I do very small throlle it craws faster...once I get it to craw I can use the second gear slightly...and if I open up the throlle after the third gear runs perfectly!

Here are my thoughts:

1. Mesh is messed up? Too tight on first gear? If this would be the case, the gear should spin? Correct? All gears spin. I pick up the truck and run the engine and no issue, all gears spin.

2. Second gear is overwritting the first? Meaning it is coming in too early? This can be adjusted. Can this actually happen though? Second gear kicking in before first? Causing the engine to skip first gear? Causing it to barely move because RPMs are too low for 2nd gear?
I'm glad you got the engine running correct!
it does happen to where the second gear can kick in too early (or even before first really has a chance to pull the truck forward.
and in this case that sounds like what is happening. it has happened to me with my mgt.

i think what is happening is the second gear is adjusted to shift too soon and when you get throttle going quickly, it throws the shoes out and engages second gear right away, if you do it slowly it has first gear slowly building then will shift to second (thought early, but it had a chance to get some revs first) thats why you are getting better acceleration.

i dont think it would be gear mesh, if one is binding, they will all have the same resistance. when you rotate the wheels with the truck off the ground is it hard to spin them? or do they spin relatively free?

Hope that helps! getting close to having this truck ripping!
 
@D3MON I adjusted the idle set screw. The idle gap was depending on the throtle arm/angle from the carb position. I adjusted the set screw so that no matter hat andlge the carb is position, it wont shut close. IT will always remain t he same because now I am using the set screw. Engine is running, thanks!

Now I have another issue! Remember the 3-speed transmission? It's acting up. If I revv up from stand still it barely crawls....if I do very small throlle it craws faster...once I get it to craw I can use the second gear slightly...and if I open up the throlle after the third gear runs perfectly!

Here are my thoughts:

1. Mesh is messed up? Too tight on first gear? If this would be the case, the gear should spin? Correct? All gears spin. I pick up the truck and run the engine and no issue, all gears spin.

2. Second gear is overwritting the first? Meaning it is coming in too early? This can be adjusted. Can this actually happen though? Second gear kicking in before first? Causing the engine to skip first gear? Causing it to barely move because RPMs are too low for 2nd gear?

Usually ,first spur gear is always locked in ,2 & 3rd gears are usually screwed or mounted to a centrifical hub ,they usually
do have an adjustment to time the engagement ,threw a pressure spring!

Looking at some of your pics ,the first gear on your bell might even be a tooth too small ,does those gears come apart or
threaded onto the clutch bell?
 
I'm glad you got the engine running correct!
it does happen to where the second gear can kick in too early (or even before first really has a chance to pull the truck forward.
and in this case that sounds like what is happening. it has happened to me with my mgt.

i think what is happening is the second gear is adjusted to shift too soon and when you get throttle going quickly, it throws the shoes out and engages second gear right away, if you do it slowly it has first gear slowly building then will shift to second (thought early, but it had a chance to get some revs first) thats why you are getting better acceleration.

i dont think it would be gear mesh, if one is binding, they will all have the same resistance. when you rotate the wheels with the truck off the ground is it hard to spin them? or do they spin relatively free?

Hope that helps! getting close to having this truck ripping!

@D3MON : I agree with you. This is my suspicion! I can move slowly using the first gear. But if I re up, I believe second gear is comin in too early. I have two options to troubleshoot: Put on a new transmission I have as a spare. Or tighten down the centrifical hub so that second gear never comes into play. If I can hit the throttle fin and do wheelies, that was my issue. My manual says it's possible to skip second gear this way, if the timings are screwed up.

I got tit to get to third gear a few times...it rips! Very excited, thanks to all of you guys! I'm glad you guys are patient and able to show others your knowledge so that this hobby could be continued.
 
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