I just bought a macstar to put in my ofna mbx buggy.I didn't get anything other than the motor and carb in the box[&o]No setting sheet/nothing.I can't find the factory settings for this motor anywhere online.I was gonna go with the settings off my force 28 but the carb is different has a screw on bottom of the fuel inlet.It fired right up, yesterday was the first try at getting it broke in.It is way fat the way they all came set.I got it to 220 and shut it down at BDC.I haven't tried again becouse i'm lost on what that other screw does and where my needles should be set at for break in.Any info on where they should be and what is the other screw on the inlet.Thanks

here ya go
its a diffrent moter but with the same carb


http://ofna.com/pdf/eng-hyper21.pdf

Thanks that should get me going.Thanks again

hey i just got my 28 running again and i set the HSN 1 n 3/4 turns down from flush setting and the LSN 3/4 of a turn out from flush setting and it works just fine. might want to try that

241 is that the new Mac-Star? turbo plug version? if not, let us know how that thing runs and holds a tune. I heard the other day in a LHS that the Mac-Star .28 that came with the Hyper ST RTR could be made to haul tail! I have to be honest tho' mine is a paperweight as I couldnt get it to hold a tune for nothing!! ran very hot and just didnt have any bottom end. once it started revving tho it would scream then get hot as hades. hope it goes better for you keep us posted.

Rican this is the old version Macstar 28.I spent hours trying to get this carb dialed with no luck [:@].I''m gonna see if I can swap the carb with one of my backup ofna''s and see how that goes.I can''t get this thing to hold a tune for more than a few passes at best.If I can''t get it to run better than it is now it will become a paper weight aswell[]I''m gonna try the carb later today.

Its sad to say but the MacStar engines are terrible motors....Pretty much worthless no matter what you do to them

Buy the carb o-ring set [link=http://www.nitrohouse.com/eng%20parts,_hyper_21.htm]here[/link]
Its quite a common fault on that carb. Alternativley look out for an OS 20E carb on ebay second hand

let me know how that carb swap goes.... like I said it hauls when its revving but there is absolutely no I mean NO low end on this thing at all!! and it likes to run hot for some reason..

I used the info from zjwhitlock and it was running but no power what so ever at those settings from the ofna site.I called a ofna tech and he told me where to set everything at so I did and tried it yesterday [:@].This carb is a total pos[:'(]I have tried everything with this motor with little sucess.I was aiming for decent temps with decent power and I'm getting good temps with absolutly no power,my other 28's will run circles around this thing and hold good tune.Well I got pissed and decided it was gonna run like I wanted or it was gonna grenade one or the other was gonna happen.After some more tuning, I got it to run pretty good.I ran the whole tank with no issues and it was running like it should had great power all the way through the rpm's.It ran out of gas so I checked the temp and it was right at 300[&o].I'm gonna run it some more today and see how it goes.This carb is one finiky sob thats for sure,Iv'e never had a problem tuning till I bought this soon to be paperweight if I can't get temps down.

Rican my other carbs are to small and won't work.I think I will be looking for another motor soon since this one won't last long at these temps.

What fuel, plug combo are you running. I had a macstar that I recently sold with one of my buggies. I to had a problem at first. I was using the suggested plug with bad results. Switched to a OS A5 and it helped. The needle settings I used. HSN 3 3/4 turns from closed, MSN flush with carb body, LSN flush with linkage collar, idle screw 1.5mm opening. Running O'Donnell 30% race blend. After that I was able to run 240-270 F with good acceleration and top end. Hope this helps. You can atleast use these needle settings as a starting point.

I have a macstar .28 with my hyper 7, but i cant seem to find the rigth tunning because it gets hot.
Does this motor is meant to run hot?

thanx

question solved
http://www.rcuniverse.com/forum/m_44...tm.htm#4479616

i really need to find some macstar .28 head screws, somebody has, o knows which size are them??? I lost one.. and im running with 3

are they not just m3 threaded cap heads? about 20mm long ish?

are you guessing, or is it the correct size for the head screws?

thanks

The 6 port Macstar is one querky engine to tune and they dont hold a tune well either.I've had 3 of them and they can be a pain in the butt.The HSN is 4.5 turns out from closed and the LSN is 2.5 turns out from closed.Be careful with the LSN it only needs to slightly touch the the Fuel supply nozzle valve very lightly when closed up.....

This is just for your future reference by the way,I have the setup sheet for the Macstar.28

do you have that sheet in pdf? can you email it to me: [email protected]. by the way don´t you know the size of the head screws?
thanks a lot

ill check the head screw size now

thanks

[:@] dang, its not metric. its bigger than m3 smaller than m4