dogman
there is papago raceway at 40st university in phoenix and the nitro pit in wittman about 30 minutes west of downtown phoenix. both have summer series races on the weekends and papago has practice nights.

My ofna valve should be here tomorrow. can't wait to see how it works out.

Here is a update, I took the Nemesis out for a tuning session with the OFNA check valve with some good results. I ran a couple of laps and it seems it was running to lean because it was runnig eractically. I turned the needles back to where I had them before I installed the check valve and started to turn the needles 1 hour at a time and found a setting with a good tune. temps were around 230, so I think I will lean it out just a tad more. I still cant seem to get the thing to idle with out stalling and when it does stall the carb is loaded with bubling fuel, dont know why this is happening or is this normal with the check valve. Overall I am pleased with this check valve and enjoy the longer run times than with the small tank I had installed previous. I was having a good time and you know it's not rc unless somthing breaks and sure enough, I broke the rear axle.
I have already upgraded the front axles but not the rear. Looks like I will be ordering a pair from www.customrccars.com. Any help with the stalling issue and the carb filling up with fuel issue will be greatly appreciated....Thanks

Hey Soilworks, sounds like you still have just abit of tuning left, The low speed needle can be leaned out more. You have the high speed pretty close by the sounds of it. Keep leaning the low speed 1/8 turn at a time, you'll get it!!

When I first started tuning for the valve I ran acrossed the same thing with the carb loading up when I stopped and I almost gave up on this valve too, but after more leaning of the low speed, it came around very nicely, and idled all day long. So dont give up lean it more!!


Let us know how it goes

Dbl posting fool!!! sorry

Thanks for all your help "Dogman"

Ahh it all sounds so familiar heh, I too had some issues re-tuning the low needle after installing the check valve. It takes some time to get it right but once it's there it's golden, my GST is running strong around 230-240s from full tank to empty tank.

Although I don't know if I have my tune perfect, I have to keep it idling a tad high to keep it happy, the clutch bell kind twitches slightly. Is that normal, or is it off a little?

dStruct, You might wanna check the springs in your clutch. Mine used to twitch but when I installed new springs that went away, but it sould be the idle is just atouch higher than needed. try idling down just abit and play with the lowspeed to see if that helps

Good Luck

Yeah, I think my idle is still a little on the high side, I'm just hesitant to lean out my LSN too much as that controls the mixture and I'm worried it might overheat. My LSN is close to flush maybe 1/2 turn in from flush, and my HSN is about 1-2 turns from flush (what is that about 5-7 turns out?) or so.

So to me it seems like my HSN is way rich even though it runs strong around 230-240F's. I'm going to take your advice and keep fine tuning the LSN, in very small increments that is..

Do those settings sounds about right?

Hey Dogman,

I just saw that pic you posted of the brake linkage in that other thread, however I noticed in the pic that your HSN is set way richer then mine, like a full turn or so. Is that because of the temperature differences out there, I mean it's not that much hotter out there really then it's been in Socal.

And can you post a quick pic of your LSN so I can compare that to mine?

I think I have it right, but it's still dying on me and acting a little funny.

Thanks!

Might as well get some use outa this page....so

dogman...have you been working on that 4 link at all? I'm thinking that with the power this truck makes that crawling wouldn't be to much for this truck with a nice 4 link setup and the 4 wheel steer. out of my price range but would love to see that 4 link

Well, I'm still fine tuning LOL, it's almost right.. How far can you turn the HSN screw before it comes out completely? I'm at work or I'd check myself

And at what point should I consider it having an air leak, my HSN is flush with the outer brass ring, and my LSN is about 1/2 maybe 1 turn out from flush. It's running 230-235's and I can tell the LSN is a little on the rich side..

Thanks!

I think if your LSN was rich you would bog out when you gun it from a stop...if I'm thinking right...

I am at work too!! but it sounds like you do have an airleak, but not a real bad one if you can tune it out. I would start looking for an airleak somewhere... Sorry can't spend much time right now, and I may have to work late, so I will check back in later to see if we can find the leak

It does sound like you have a air leak. If you are tuning the high speed needle to the point were it's going to come out and you are running those temps then there is a air leak, that is way to rich on the hsn. you should start from factory settings and turn the hsn clockwise. To check for a air leak do the simple things first.

1. check fuel and pressure lines for cracks or holes
2. Loosen the carb binding nut, remove aircleaner and press down on carb and retighten the nut, sometimes the carb is not pressed in fully.
3 Submerge the tank in water, blow into one of the lines squeezing the other so air can not escape. If you see any bubbles coming from the tank then the tank has a fracture.

If theese simple things dont produce any results then you will have to pull the engine out and seal the carb and the back plate. Have you noticed any fuel around the backplate or the flywheel, if so than you have a bad bearing in your engine (another culprit of airleaks)

Hmm I'll check into all the things you guys brought up, good advice, I have a feeling I checked the carb set screw and when I tightened it I wasn't pushing down on the carb, maybe that's all it is (wishful thinking).

I can tell you there is no fuel or gunk anywhere there shouldn't be, the head is sealed up nicely, the backplate and front seal look good, but the tuned pipe where it comes apart in the middle has some gunk from where the rubber o-ring inside isn't being pushed into the groove, when I took out the cone looking baffle it was helping to hold it in place.. But it's very minimal buildup.

The weird thing is the temps are dead on consistent within 5 degrees F or so, and when I say the LSN feels rich, it doesn't accelerate quite as good as it could, it's very minimal like it almost wants to stumble when I left off but it doesn't. I'm just hesitant to lean out the LSN as I may need to compensate that with more HSN, I'll post some pics of my needles when I get home in an hour.

If I back the HSN out more then flush how much room do I have before it comes out?

Thanks guys!

Pull the header off and check the gasket. it could need to be replaced. It doesn't take much for a airleak, the smallest hole or crack is all you need!

Motor is BRAND NEW, like a week old.. I've run about 15 tanks on it.. You think it could be cracked?

Not the engine, just the rubber gasket.

Soil is absolutely right, if your rubber gasket at the header on the block is in any way allowing air into the system and you will be overheating. That gasket needs to be pristine and seated properly!! All it takes is a pin hole air leak to cause the minimal heating you seem to be experiencing..

Hmm, ok I reseated the carb and it didn't make much if any difference in temp or performance, I have yet to pull the motor out and check it as it's running great. I mean it runs strong and I really have nothing to complain about the LSN is a little on the rich side to keep the motor temps at bay, 235-240 consistently, maybe it's the new fuel.. I switched from Werks to Byron's maybe it's just running differently from what I was used to before..

Hey the rubber gasket you're talking about, are you referring to the backplate seal? That little o-ring?

Thanks all

dStruct lower right corner of manual page circled in red is the gasket we are talking about

OOOOOOOhhhhh,

THAT little gasket, yeah that actually could be the culprit, the header likes to tweak itself in a weird direction, like it's sitting crooked and I noticed this on my other NX-76 too. That very well could be my issue, the gasket isn't seated evenly that's for sure, and I can see that without even removing the header.. [:@] Shouldn't it fit a little tighter around the exhaust port?

Hey TRD, have you shaved the inside of the header at all? If you look into your header on the motor side you can see where it has a 2 little spots the stick out sorta, at least mine does. It's just asking to be Dremel'd smooth.

EDIT: What purpose does the silcone tube around the header serve, is it just for heat dissipation, like to keep the heat off the shock right there or plastic around it or what?

That a great question, I always thought the silicone tube was a connector, thinking the header is two seperate pieces, but on a closer inspection it looks like the header is one piece.

It's there, actually to protect it from the shocks from wearing a hole into the header since it's only aluminum, very soft aluminum... I realize when you remove it you will have like an 1/8" but if you land hard on the rear you will actually push the shock tower into it. I installed one my Rear Toe Rods from the top of the shock tower to the front of the engine mounting plate to help that from happening I think ther is a pic of it in my gallery(I need to update my gallery) If not let me know and I will get one.