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Mach .15 problems

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S

SmokinFast

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Alright i am at a loss. within the first week of having my xxxnt the pullstart had begun to slip after every time i ran the car and shut the engine off. that was since early january. basically i just dealt with it until about a week ago. i then went and changed the backplate thinking that might be it, no dice. i then changed the one way bearing, still no dice. so then i changed the starter shaft (the little bolt) and that worked for about a day and a half, then no dice after that. so like i said i am at a loss and i could really use some help.
 
When the one way bearrings get too oily, to greasy, or too sludged up they quit working.

My suggestion for you. next time oyu have the PS off, drill a tiny hole in the bottom of the plastic PS case.

When it starts slippen' , stick the end of a wd40 can in there and give it a thorough hosing. You will find it will work much better.

They also fail a lot on breakin.

My thougts as tto why you are having problems.

#1 breaking in still?
#2 runningina bit too rich
#3 too much oil content in your fuel

Hope this helps
 
i know that the starter shaft not the bearing is slipping and that is cause it is oily of course, i knew that. my ? is why the hell is it doing that! by the way the way the pullstart is set up makes the "hosing" impossible. and the nitro i use is what the company says to use 20% and as for to rich that isnt it cause its runnin at the "optimum" temp

after all the parts I've replaced and stuff i just need to find out why every time i run the car i have to clean the shaft and the inside of the bearing because theyre slipping
 
I'm just letting you know the oil in the shaft gets there from the fuel. I wasn't saying you are doing anything wrong. I was pointing out what does make a one way slip, and how to fix it.

The point is the oil from the fuel is getting on the shaft. It's also gettting on the one way bearing. That's what is causing it to slip, every time.

If you drill a small hole in the bottom of the pullstart case, and shoot either wd40, or brake cleaner in the hole, it WILL make it to the one way bearing and shaft.

That is about the only way to clean it without pulling off the backplate, and the P/S. I've done it, it works.

One way's and the shafts are just a pain in the butt. It's the nature of all of them, not just yours.

G'luck
 
I think it may also be that it's a cheap engine. I have the truck as well and remember mine doing the same. I think the one-way, shaft and pull start mechanism are all pretty cheaply made.

I've since dropped in an OS 15 cv-r(x). This thing rarely slips and I am getting way more life out of it than I did with the MACH.
 
Hey olds, did you aget alot more power out of the new os VS the new mach?

I know the OS would be faser than the old mach lol, did you have the mach when it was new?

Reason I am asking is that I am considering replacing my mach with something better.
 
I bought the xxx-nt brand new with the mach in it. It was my first nitro vehicle. I destroyed that engine pretty quickly. Probably less than 3 gallons. First time, didn't break it in, didn't know what a manual was... you know, a newbie story.

I first attempted to rebuild the mach. So I wasted $ on a new piston/sleeve and connecting rod. It still ran like crap. I futzed with it for a few weekends and couldn't get it running right. So, I decided a new engine was on the menu.

I bought the os 15 cv-r soley on the fact that the LHS guy said it was a good engine. Fortunetly, he wasn't lieing. If I remember correctly, it was a drop in. Didn't have to modify anything.

The OS rips of the trans pretty bad though. It's a very good engine for an ST. Plenty of power, easy to tune and friggen fast. I'll be starting gallon #7 on that engine when it warms up outside, or when I get entirely fed up with my maxx.

To avoid blowing the trans every time out if you get this engine, get a RRP aluminum monster diff gear and someone makes a good diff adjusting nut, but I can't remember who. I also put in losi's carbide diff balls when I bought the RRP gear. Before I upgraded to these mods, I had rebuilt the diff 4 times in a gallon. After the mods, I havn't even cracked the trans case open in 5 gallons.

You do the math.
 
Yes guys, the CVR is fast.....very fast......but and a big but is if you run on short tracks and not WFO style tracks it is tooooo fast.

I remedied the pullstart problem on my NT by spraying Nitro Clean in the hole the rope goes thru....it will penetrate to the bearing good enuff to start it.

I also am going to say unless you run on tracks with 100 foot straights or you just bash you CAN run the mach motor to its potential and it will still be controllable. I have a Megatech M-16, .12 CVR, and yes they are faster but for bashing I don't like to put wear on a good race motor.

Tune that Mach till its right and add a AE Factory Pipe and it will run fairly well with even the mighty CV-R. I found that my Mach runs best on a low oil percentage fuel.

I am in no way saying the Mach is better than the CV-R. What I'm saying is that if you can't upgrade your engine there are ways to get more power out of the Mach till you can.

I run run mine arounf 215 degrees and it runs fine. Its not the fastest thing around but its easier to drive on a tight indoor track than a CV-R or even the M-16.

Also , if you go spend 150 bucks (not to mention the tranny upgrades) or so on a CV-R pullstart engine you will have the exact same problem from the one way bearing. Actually I had more trouble out of that style than did I the one on the Mach. Buying a new pullstart engine , no matter what type, will not fix or do away with the pullstart blues.

Just my opinion here but I think I would buy a starter box first and this

http://www.dynamiterc.com/Products/Detail.aspx?ProductID=DYN6534

and eliminate the pullstart. You will gain some more power from the mach and then when you upgrade to a faster better engine you can get a non pullstart and be set up right.

Just my $.02 worth

-Sag
 
The mach .15 awakens.

I have axtm .18 it's a wild one. It really cranks out the HP for it's size. tonight I was tuning the mach .15 and running it around.

I was wondering really wha the big difference was. Is .02 cm really that big a difference?

The only difference I saw was the pipes. So I switched pipes, and put the XTM .81 pipe on it. Wow, it really woke it up. It held a tune better, and has way better low end, and a bit better high end as well.

If you have a sweet running engine, try throwing that engine on your mach. It might just surprise you.
 
I was thinking of changing the engine in my XXX-NT as well. It has the Mach .15. But I had the same problem as SmokinFast. All I did was take the pull starter off and cleaned out the one way bearing with some WD-40. But you have to take the back plate off the engine to get to the bearing. After that it worked fine.

What kind off engine do you recommend for a XXX-NT?
 
As I said up above, the OS 15 cv-r(x) is a good engine for a stadium. Almost to much power for the xxx-nt's fragile trans. After a few hop-up's in the trans, it's all good though.
 
I'm sorry I was so excited above I mis typed. I put the XTM PIPE on the mach .15, and it really did wake it up.

The mach .15 I have is in my maxx. I was completely surpised by the power it gained. All i did was put the xtm pipe on it.

I' satisfied with the power the Mach puts out now for my maxx..

Sorry grrr I hate when I mistype a post like above then it sits for along time.

If you have another pipe on a easy to tune-good power rig. try puttting that pipe on the Mach .15 and see what it does.
 
I have the XXX-NT with the Mach .15 and I have been totally pleased with the engine since day one, It has never NOT started with just a couple of tugs on the pull start. Not only is it easy to start and tune...it feels almost over powered for the Losi. Its a great bashing engine.

sLY


Originally posted by Wildcatfreek
I was thinking of changing the engine in my XXX-NT as well. It has the Mach .15. But I had the same problem as SmokinFast. All I did was take the pull starter off and cleaned out the one way bearing with some WD-40. But you have to take the back plate off the engine to get to the bearing. After that it worked fine.

What kind off engine do you recommend for a XXX-NT?
Click to expand...
 
I had the same thing happen to my Mach .15 when i got my losi. There are a couple of things you have to do to get it to a good operating engine. First thing I did is drill a small hole in the middle of the pullstart, That will let any fuel or oil in the pullstart case escape so it wont make it slip. Second thing I did was seal up the whole engine with silicon to insure that NO air leaks would happen. Mach .15's are commen with those. Then basically oil it and keep it running good. There pretty easy to tune. Hope you get it to run good man. See ya! -Colton :banana:

Also if you want a new engine as i saw the post. I would get a .18. The XTM one that comes with the truck seems to be a pure Beast!! Check into those... Or if you want a screamin engine get a O.S CV-R .15. They are killer fast and are a blast to tune.

Also MSLY is right, It does start up great every pull if you have it set right :)
 
BTW the XTM .18 motors on the back of hobbypeople.net 's cataloge $79.99

OKay I gota mach Q now. I slapped an OS 10e carb on it (actually came with the carb) I sealed it all up and put a new p/s in it. I just can't seem to get tuned right.

Either so rich it bogs, or so lean it stalls out overheated. Any ideas? The XTM pipe really woke it up, but it is still a pain to get dialed in.
 
hmm... os carbs are usually the easier carbs to tune.. temp it and see how long it idles before it dies.. then we'll talk bra
 

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