spikeman

Thays funny I had a Mach.28 and it was great. Stared 2nd pull every time. You have probably already tried this, but did you set it to the manual settings?

Big Daddy05

Yes I have put it back to the stock settings. I think my problem is the roto start since I no longer have the pull start.

Does Mach.28 = Mac Star .28 because I thought they were different engines

sn00p

OK dude. Drills are NOT the ideal starting mechanism they tend to be too slow working in reverse (reverse required to start the engine and crank it in the right direction) The also tend to not have enough torque especially the cheap DIY jobbies. They also do not have a 10 second cutoff Therfore i dont not recommend. A proper roto start or similar is a much better idea.

Once your truck is fairly well tuned i see no problem with the pull start. If im honest i was going to get a roto start of some kind but im yet to have an issue with the pull start. I yank the chord maybe 10 times with my finger over the exhaust stinger to prime the fuel. I then open the throttle pull the chord a couple of times to get fuel inot the crank. Put the glo starter on leave for a few seconds and then pull the cord most usually no more than 3 times to get it started....

If by this time it hasnt started i remove the glo plug and check its working and drop just a few drips of nitro directly into the cylinder. ALWAYS starts after this.

Me personally seeing you got the roto start backing plate in place i would spend the extra few bucks for a genuine starter mech especially if your newish to nitro as the pull starter do tend to break and you need to be aware you DON NOT tug them the full length of the chord and neither do you apply excessive strain. The roto start will allow you to spin up a semi flooded engine without to much issues. Just dont over do it and do 10 second burts max with a 10 second gap inbetween.

I guess if your tight for dollar then now you have the engine tuned-ish try the pull start. I would personally take my drill to the LHS and see if them guys can start it with that first and then just ask them for tips.... You'll be surprised how helpful they can be and they know full well everyone has to start somewhere and learn right from the beggining.

Im just checking but you DEFINATELY have the drill in reverse right???

sn00p

Oh and once your all happy and up and running i suggest you carefully take note of your screw/needle settings. Post them back here as i would be interested. DO NOT bother with the mid needle we dont want to go back down that road again lol but i would certainly be interested in the LSN and HSN. Just remember when screwing them shut DO NOT over wind or you will damage the end of the needle. Just screw them in (clockwise until you get resistance). Make sure you have NO distractions so you can carefully count 1/2 turn at a time.

I sure hope you have a good weekend with much fun. Once you get the hang of things and tuned etc you will be very stoked.

Big Daddy05

Thanks snoop,

This roto start is specfically made for the Hyper ST and the LHS guy told me it is specifically for a 12V Drill. I tried a plug in drill that has much more RPMS last night but still no luck. I am hopefully going to get to the LHS on lunch, I will let you know what they tell me. I am bringing all my starting equipment to see if it is me or the equipment.

Thanks again

sn00p

is th drill in the reverse??? i.e turn left as you look down the back of the drill to the front. Or if its facing you then then it should be clockwise

Sorry bud just trying to help you out.... Im certain them guys will have you up and running for the weekend. Im feeling your pain dude i had a nightmare with my 1st nitro it takes a little getting used to.

Big Daddy05

Ok so here is the update. I got to the LHS today and the guy was able to start it using his drill. My drill does not have enugh RPMS. Anyway, we got it running and of I went.

It was awesome!!!! I finally got to run it on the track. It handled great, although I don't have much to compare it to. I think it was a little lean on the low end. At least that is what the guys there said. So tomorrow I shall richen it up and see how we do.

The bottom line is, I bought a bump start. The guys there said that this will elimate my starting problems. I still think that the roto start is stripped a little but, the bump start should work great!

I left the truck there so the guy can line up the bump start. I will check the needles tomorrow and let you know.

spikeitaudi

Good to hear that you solved your problem with starting.

sn00p

Hopefully your now on to weekend after weekend of fun. Did you manage to jot down them settings yet???

Big Daddy05

So I was hoping you guys would have some input for me. I am trying to tune this MacStar engine and I seem to be doing good on the top end. When I first get the truck going, the low end is very responsive. After the engine heats up the low end seems a little sluggish and it takes longer to get up to speed. I am concerned about this because at the tack I will not be able to pull out of the corners. I am thinking I am still too rick on the LSN, any thoughts?

adam-69

what clutch beel you running in her? from experience mach .28s are lacking on the bottom end a fair bit. what pipe also?

Big Daddy05

I have the ST RTR, so I am still running the stock pipe and clutch bell.

The thing that gets me is the low end power seems to hesitate more and more during the course of running a tank.

adam-69

to be honst mach .28's are ****, they run really hot, dont hold a tune, and from my expierience lack bottom end, i would just lean the low end in till your happy, its what i did with mine. just burnt it and whipped a go in as soon as the mach popped!

sn00p

NO............................................

Thats exactly what mine was doing... its because the bottom or LSN is too LEAN..... richen that fecker up like out to 7.25 turns out.... the reason it bogs the longer (hotter) the engine runs is because its getting hotter and leaning out becuas the tank is leaning too...

Ive richened mine to the point where i see no gain but NO longer have the hesitant bog etc... screams right the way up but still a little slow (no bog or hesitant though) off the VERY bottom. Once its moving a little its very responsive. So i have now chosen to go with a 13t clutch bell.... stock is 14t so should give me good off bottom acceleration. HAvent had a chance to trial it out as its been snowing here over the easter holiday but will post back.

Big Daddy05

Snoop, sounds good, I will try the LSN around 7-7.25, and then leand out the HSN, what fuel are you running? I am running 30% with a Mccoy #8 glow plug. I imagine that this can make the difference.

Thanks, I will let you know the results

sn00p

im running os8 plug same as mccoy 9 and byrons 25%. dont go straight to 7.25 just keep unwinding it 1/4 turn at a time (from where you are until you notice less bog (keeping a log of where your at total ) once you have rid of most of the hesitation bog move needle 1/8 turn at a time until you get your best results.... Just make sure your happy with the HSN before touching the LSN. I then just go back to the HSN for a final fiddle to make sure im in the middle somewhere.

you sound like your VERY nearly there. Good luck and dont forget to post back with final settings.

Im hopinh to get out tonite to see how the 13t clucth bell makes a difference. will post back asap.

Big Daddy05

Ok, so the weather has been very un-cooperative hear in New Engalnd. I took the truck out on the weekend and that is when I noticed that the performance started to dwindle as the engine heated up.

Today I took it to the track and it was the same thing. It was very sluggish until I got to the mid-range. I tried richening the LSN a quarter turn at a time, but it ended up stalling. I did lean it our again just to finish the tank, but now I am confused.

When I got home, I get the needles and they were at;

LSN- 5
HSN-3 1/4

So needless to say I need to lean it out. But the forcast is calling for rain the next few days. I need to get this right because I am developing Nitro Fever. I know the easier thing to do would be buy a better engine, but there are other things I would like to get, so if I could get this enginge running decent I would prefer it.

Any advice?

sn00p

Hmmmn my engine stalls at anything laround the 4.5- 6 on the LSN anything under 4.5 like flush runs with a horiffic bog. My words are to try 7.25 on the lSN at worst its too rich and will not run clean.... you will NOT do any damage its deffo worth a try. I had to richen mine 1/2 turn on the HSN yestrday as it was raining (prolly a wet filter too).

Im not saying my settings are the greatest in the world and nor do i say they will work for you but its deffo worth a try. Like i said if your engine drops off when its getting hotter then your running to lean. I had the same issues and thought it strange that i needed to run MUCH richer than the manual states stock... try 7.25 you may need to fidle with the tick over screw just to get the engine to idle correctly ( i know i did) its item 21058 a small flat head screw kinda on the side of the carb (not the screw that holds the carb in plave though)

http://www.hobao-racing.com/download...%20Diagram.pdf

if you find the truck runs ok at 7.25 on pickup just keep an eye on the top end and temperatures. for me im around anywhere between 1.8 and 2.5 depending from day to day on the HSN

On another note i tiralled the 13t clutch bell in hope it would ease the slow pickup but to be honest it made no - little difference. It still had very slow off the VERY bottom and then rapidly picked up (created to much spin). Its prolly better with the stock 14t a lot smoother. You just need to make sure you at least keep the truggy crawling so you dont notice the lag. Like ive always said once its on song its a good engine and plenty powerful enough in my opinion for MOST users.

Big Daddy05

Thanks Snoop! My plans are to continue to try an richen the LSN, I will start at 6. I will let you know!

Big Daddy05

Hey Snoop,

I got the truck out again yesterday. I warmed it up and then started to tune it. I got the HSN down to 2.5-2.25 and I was impressed with the top end.

The probelm I had was the LSN. At about 5.5 the bogging continued to get worse and it constantly stalled making it hard to start again. I got he LSN all the way up to 7, which at that mark it would not even start.

Any thoughts? I think my plans are for a JPX .28 unless I can figure this thing out.

sn00p

that not good dude... i guess you gotta at least try moving your needle the other way (leaner). Like i say each mill is different just dont give up on it just yet... treat it as a good learning curve for nitro tuning... this will be 1 of the hardest mills your likely to tune so its all good from here on.

Big Daddy05

Anyone else having trouble turning? I have upgraded the servo to a hitec 645 which is not the best but should certainly do the job. The wheels turn no problem off the ground. When I place them on the ground the servo seems to turn slightly pause and then continue.

I am using a 1600 MAh hump pack, and I know that it is fully charged. Anyone have any ideas? I am thinking about taking the steering column apart, but not sure if it needs to be oiled, or greased or something else.

madmax22

does it do this wile driving? some times my servo has a hard time moving the tires wile its sitting still......

Big Daddy05

While driving the turning seems to be worse than when I had the stock servo. I wish I still had it to test but I blew it up. So I woudl say that it does do this when I am driving because the turning radius seems to be hindered.

sn00p

you are using the servo horn that came with the hitec servo right???? only the stock alloy servo horn that came on the truck doesnt fit the spline of the hitec. Whenever you play around with the horn or servo make sure to power OFF the servo or you will end up shearing the gears

A quick test would be to remove the servo horn from the servo and then by hand turn the steering and see that you have NO binding and that it is easy to trun to full extent in both directions. that way you can narrow it down to either servo or steering assembly.