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Old Dec 30, 2002, 08:12 PM
free.teranews.com
Guest
n/a Posts
Nearly another 'how to tune my engine' question

Hi all,
I really need some advice on this.
I have 3 Traxxas nitro cars, a Rustler, 4TEC and of course the TMAXX. All
have the TRX 0.15 engine in them.
The Rustler runs great - very fast very powerful - it is also the oldest at
3 years old...
The 4TEC is not bad - but seems to have (and always has had) huge amounts of
compression compared to the other two - once running it tunes in and runs
very well, it is just a bit of a pig to start sometimes.

The TMAXX though is odd. When I first got it (about 9 months ago) I could
run it all day with no problems at all, I would have said it was the best of
the 3.
It now starts very easily and will run quite well for about 5 minutes. It
then starts to sound as though it is running hot (clacking sound, uneven
tickover) and the water drop test suggests that it really might be a bit
hot. To compensate for this I richen the mixture (top end) and obviously it
makes a difference to the power, but does not seem to cool the engine down
and I still have the uneven running at tickover. I have tried adjusting the
bottom end mixture instead and all I do is get a truck that will stall if I
accelerate too hard and is still hot. The basics of this problem are if I
set it rich enough to keep cool the thing has no power and splutters like
mad.
The driving I do is a mixture of high speed and low speed - not that this
seems to change the symptoms.
All the engines were run in the same and exactly as per the instructions.

So far I have done/ checked for...
Dirt in the fuel line
Dirt in the carburettor (disassembled and cleaned)
Damage to the mixture needles
Dirt / damage in the engine (not disassembled - just looked for score marks
on the piston and crank)
Ensure the air filter is clean
Leaks in the fuel line etc
Binding gear train
Binding clutch (at tickover)
Avoiding driving on grass (not that I have done this much anyway)
Reset to factory tuning settings and start again

I use 20% blue thunder fuel in all the cars and wonder if fuel is
contributing to the problem (not that I have had any problems before), but
why would it work in the other 2 cars?

Sorry to post another subject on 'how do I tune my engine' but I am getting
very frustrated with this now.
Please, please help me with this, it is spoiling my fun!!

Thanks
Garry


Old Dec 30, 2002, 10:12 PM
TempestNightmare
Guest
n/a Posts
Re: Nearly another 'how to tune my engine' question

The clacking sound makes me think either the piston and sleeve are worn, or
the con rod is trashed.......
Jon

"free.teranews.com" <%gpriestland%@lineone.net> wrote in message
news:3e10c08a$1_6@news.teranews.com...
> Hi all,
> I really need some advice on this.
> I have 3 Traxxas nitro cars, a Rustler, 4TEC and of course the TMAXX. All
> have the TRX 0.15 engine in them.
> The Rustler runs great - very fast very powerful - it is also the oldest

at
> 3 years old...
> The 4TEC is not bad - but seems to have (and always has had) huge amounts

of
> compression compared to the other two - once running it tunes in and runs
> very well, it is just a bit of a pig to start sometimes.
>
> The TMAXX though is odd. When I first got it (about 9 months ago) I could
> run it all day with no problems at all, I would have said it was the best

of
> the 3.
> It now starts very easily and will run quite well for about 5 minutes. It
> then starts to sound as though it is running hot (clacking sound, uneven
> tickover) and the water drop test suggests that it really might be a bit
> hot. To compensate for this I richen the mixture (top end) and obviously

it
> makes a difference to the power, but does not seem to cool the engine down
> and I still have the uneven running at tickover. I have tried adjusting

the
> bottom end mixture instead and all I do is get a truck that will stall if

I
> accelerate too hard and is still hot. The basics of this problem are if I
> set it rich enough to keep cool the thing has no power and splutters like
> mad.
> The driving I do is a mixture of high speed and low speed - not that this
> seems to change the symptoms.
> All the engines were run in the same and exactly as per the instructions.
>
> So far I have done/ checked for...
> Dirt in the fuel line
> Dirt in the carburettor (disassembled and cleaned)
> Damage to the mixture needles
> Dirt / damage in the engine (not disassembled - just looked for score

marks
> on the piston and crank)
> Ensure the air filter is clean
> Leaks in the fuel line etc
> Binding gear train
> Binding clutch (at tickover)
> Avoiding driving on grass (not that I have done this much anyway)
> Reset to factory tuning settings and start again
>
> I use 20% blue thunder fuel in all the cars and wonder if fuel is
> contributing to the problem (not that I have had any problems before), but
> why would it work in the other 2 cars?
>
> Sorry to post another subject on 'how do I tune my engine' but I am

getting
> very frustrated with this now.
> Please, please help me with this, it is spoiling my fun!!
>
> Thanks
> Garry
>
>



Old Dec 31, 2002, 03:02 AM
Mr R. Laramee
Guest
n/a Posts
Re: Nearly another 'how to tune my engine' question

tempestnightmare is on the money, id say the sleeve is gone needs a rebuild
kit...


"TempestNightmare" <tempestnightmare@comcast.net> wrote in message
news:EbadnVC4X_ZrlYyjXTWc3g@comcast.com...
> The clacking sound makes me think either the piston and sleeve are worn,

or
> the con rod is trashed.......
> Jon
>
> "free.teranews.com" <%gpriestland%@lineone.net> wrote in message
> news:3e10c08a$1_6@news.teranews.com...
> > Hi all,
> > I really need some advice on this.
> > I have 3 Traxxas nitro cars, a Rustler, 4TEC and of course the TMAXX.

All
> > have the TRX 0.15 engine in them.
> > The Rustler runs great - very fast very powerful - it is also the oldest

> at
> > 3 years old...
> > The 4TEC is not bad - but seems to have (and always has had) huge

amounts
> of
> > compression compared to the other two - once running it tunes in and

runs
> > very well, it is just a bit of a pig to start sometimes.
> >
> > The TMAXX though is odd. When I first got it (about 9 months ago) I

could
> > run it all day with no problems at all, I would have said it was the

best
> of
> > the 3.
> > It now starts very easily and will run quite well for about 5 minutes.

It
> > then starts to sound as though it is running hot (clacking sound, uneven
> > tickover) and the water drop test suggests that it really might be a bit
> > hot. To compensate for this I richen the mixture (top end) and

obviously
> it
> > makes a difference to the power, but does not seem to cool the engine

down
> > and I still have the uneven running at tickover. I have tried adjusting

> the
> > bottom end mixture instead and all I do is get a truck that will stall

if
> I
> > accelerate too hard and is still hot. The basics of this problem are if

I
> > set it rich enough to keep cool the thing has no power and splutters

like
> > mad.
> > The driving I do is a mixture of high speed and low speed - not that

this
> > seems to change the symptoms.
> > All the engines were run in the same and exactly as per the

instructions.
> >
> > So far I have done/ checked for...
> > Dirt in the fuel line
> > Dirt in the carburettor (disassembled and cleaned)
> > Damage to the mixture needles
> > Dirt / damage in the engine (not disassembled - just looked for score

> marks
> > on the piston and crank)
> > Ensure the air filter is clean
> > Leaks in the fuel line etc
> > Binding gear train
> > Binding clutch (at tickover)
> > Avoiding driving on grass (not that I have done this much anyway)
> > Reset to factory tuning settings and start again
> >
> > I use 20% blue thunder fuel in all the cars and wonder if fuel is
> > contributing to the problem (not that I have had any problems before),

but
> > why would it work in the other 2 cars?
> >
> > Sorry to post another subject on 'how do I tune my engine' but I am

> getting
> > very frustrated with this now.
> > Please, please help me with this, it is spoiling my fun!!
> >
> > Thanks
> > Garry
> >
> >

>
>



Old Dec 31, 2002, 06:32 AM
Garry P
Guest
n/a Posts
Re: Nearly another 'how to tune my engine' question

I have less than half a gallon through it! Probably not even that!

My description of the noise is probably not too good - it is very difficult
to describe. It does not *exactly* sound mechanical so I don't think it is
the sleeve etc but then I do not know how to check it.
I have checked the compression by pushing the flywheel with my finger - both
when cold and hot (the flywheel gets pretty hot too!) and it is quite
difficult to push round one revolution. The compression is less though when
hot.
The Rustler is much easier to turn than the MAXX or 4TEC but runs the best
at the moment! The MAXX also runs very strong when cold...

What do I look for if I do take the engine apart?

Thanks in advance

GarryP

"TempestNightmare" <tempestnightmare@comcast.net> wrote in message
news:EbadnVC4X_ZrlYyjXTWc3g@comcast.com...
> The clacking sound makes me think either the piston and sleeve are worn,

or
> the con rod is trashed.......
> Jon



Old Dec 31, 2002, 07:02 AM
Mr R. Laramee
Guest
n/a Posts
Re: Nearly another 'how to tune my engine' question

ok its like this there can only be one thing wrong with it.
let start from the beginning and work from there.

20% good fuel not something been setting for a year!
ok check plug.
check fuel line free from crap and residue pin holes.
check fuel line going to exhaust pipe make sure its fitted properly and
working well.
check fuel tank (this is good possibility) make sure o ring makes good seal
around lip of opening. no cracks in tank or anything that could impede its
implementation.
make sure the plug has its copper seal ring in place and tight enough.
next. start engine and look for fuel that may be coming out of a spot like
anywhere it should not,
eg, back plate to crank case, front bearing( this is anther good choice),
head, glow plug.
if it all checks out my friend that only leave one thing!
that there is something wrong inside and the only things that can go wrong
inside are the piston, piston rod, wrist pin, crank shaft, ballbearings, and
lastly the liner. that's it for the engine end.

as for the carb look to make sure all your needle valves are well still
needles. and that the crab is still under seal that's it for the carb.

good luck

"Garry P" <%gpriestland%@lineone.net> wrote in message
news:3e117984$1_3@news.teranews.com...
> I have less than half a gallon through it! Probably not even that!
>
> My description of the noise is probably not too good - it is very

difficult
> to describe. It does not *exactly* sound mechanical so I don't think it

is
> the sleeve etc but then I do not know how to check it.
> I have checked the compression by pushing the flywheel with my finger -

both
> when cold and hot (the flywheel gets pretty hot too!) and it is quite
> difficult to push round one revolution. The compression is less though

when
> hot.
> The Rustler is much easier to turn than the MAXX or 4TEC but runs the best
> at the moment! The MAXX also runs very strong when cold...
>
> What do I look for if I do take the engine apart?
>
> Thanks in advance
>
> GarryP
>
> "TempestNightmare" <tempestnightmare@comcast.net> wrote in message
> news:EbadnVC4X_ZrlYyjXTWc3g@comcast.com...
> > The clacking sound makes me think either the piston and sleeve are worn,

> or
> > the con rod is trashed.......
> > Jon

>
>



Old Dec 31, 2002, 05:52 PM
Garry P
Guest
n/a Posts
Re: Nearly another 'how to tune my engine' question

I have less than half a gallon through it! Probably not even that!

My description of the noise is probably not too good - it is very difficult
to describe. It does not *exactly* sound mechanical so I don't think it is
the sleeve etc but then I do not know how to check it.
I have checked the compression by pushing the flywheel with my finger - both
when cold and hot (the flywheel gets pretty hot too!) and it is quite
difficult to push round one revolution. The compression is less though when
hot.
The Rustler is much easier to turn than the MAXX or 4TEC but runs the best
at the moment! The MAXX also runs very strong when cold...

What do I look for if I do take the engine apart?

Thanks in advance

GarryP

"TempestNightmare" <tempestnightmare@comcast.net> wrote in message
news:EbadnVC4X_ZrlYyjXTWc3g@comcast.com...
> The clacking sound makes me think either the piston and sleeve are worn,

or
> the con rod is trashed.......
> Jon



Old Dec 31, 2002, 11:02 PM
TempestNightmare
Guest
n/a Posts
Re: Nearly another 'how to tune my engine' question

After you take the engine apart...push the piston through the sleeve from
the bottom up...if it goes right through...buy a new set...the piston should
stick when it gets to the top of the cylinder...
Jon

"Garry P" <%gpriestland%@lineone.net> wrote in message
news:3e121d25$1_2@mk-nntp-1.news.uk.worldonline.com...
> I have less than half a gallon through it! Probably not even that!
>
> My description of the noise is probably not too good - it is very

difficult
> to describe. It does not *exactly* sound mechanical so I don't think it

is
> the sleeve etc but then I do not know how to check it.
> I have checked the compression by pushing the flywheel with my finger -

both
> when cold and hot (the flywheel gets pretty hot too!) and it is quite
> difficult to push round one revolution. The compression is less though

when
> hot.
> The Rustler is much easier to turn than the MAXX or 4TEC but runs the best
> at the moment! The MAXX also runs very strong when cold...
>
> What do I look for if I do take the engine apart?
>
> Thanks in advance
>
> GarryP
>
> "TempestNightmare" <tempestnightmare@comcast.net> wrote in message
> news:EbadnVC4X_ZrlYyjXTWc3g@comcast.com...
> > The clacking sound makes me think either the piston and sleeve are worn,

> or
> > the con rod is trashed.......
> > Jon

>
>



Old Jan 01, 2003, 10:02 AM
Garry P
Guest
n/a Posts
Re: Nearly another 'how to tune my engine' question

Thanks for your great help...see in body of text below....

"Mr R. Laramee" <ray015@shaw.ca> wrote in message
news:wxfQ9.200801$Qr.5383291@news3.calgary.shaw.ca ...
> ok its like this there can only be one thing wrong with it.
> let start from the beginning and work from there.
>
> 20% good fuel not something been setting for a year!

Fuel is about 2 months old but I have bought some new stuff - will try the
new stuff ASAP

> ok check plug.

I have changed the plug once (for a Traxxas plug) and it did not seem to
make a difference. The new plug did foul up quick though. Or at least I
think it did, what should a good plug look like? I could try and post a
picture of the plug in the binaries if it helps.
It does glow anyway!

> check fuel line free from crap and residue pin holes.

Fuel lines replaced to prevent any pinholes

> check fuel line going to exhaust pipe make sure its fitted properly and

working well.
Made sure the split pipe was not leaking/loose, and changed the tubing from
the pipe to the tank.

> check fuel tank (this is good possibility) make sure o ring makes good

seal
> around lip of opening. no cracks in tank or anything that could impede its
> implementation.

We might have something here - there is possibly a crack in the top of the
tank. I know it sounds funny but its a bit difficult to decide if it is a
crack or not. I blew a small compressor into the tank from the fuel nipple
and blocked the pipe nipple with my finger and the lid popped off! Seems not
to be leaking air but I will replace it anyway since I have one.

> make sure the plug has its copper seal ring in place and tight enough.

I assumed this to be OK because the compression was good. The copper ring
looks undamaged too.

> next. start engine and look for fuel that may be coming out of a spot like
> anywhere it should not,
> eg, back plate to crank case, front bearing( this is anther good choice),
> head, glow plug.

After a run today there seem to be no leaks on the engine, carb seal front
bearing etc but the tank did seem a bit "wet" with fuel on the outside -
perhaps the tank is leaking...

> if it all checks out my friend that only leave one thing!
> that there is something wrong inside and the only things that can go

wrong
> inside are the piston, piston rod, wrist pin, crank shaft, ballbearings,

and
> lastly the liner. that's it for the engine end.

Oh no! Not inside the engine. Would I be looking for scoring/play in the
engine? In my (short) experience bearings will tighten/sieze or break up so
should be easy to spot. Would I see wear on the piston or the sleeve or
would it be too small to see?

> as for the carb look to make sure all your needle valves are well still
> needles. and that the crab is still under seal that's it for the carb.

The carb seems in very good condition and is sealed OK to the crankcase, in
which case I hope the fault is with the fuel tank!!

>
> good luck

Sounds like I might need it...
Funny thing is though it ran perfectly today for about 45mins non stop
showing non of the previous symptoms.

I will probably leave the things as they are for now to see if it has the
problems next time I use it with the new fuel. If they come back I will
change the tank and see how it goes. I would still like to know what it
was/is though - I don't like it when things mend themselves.

Thanks again.
Garry


Old Jan 01, 2003, 03:02 PM
MLogan9235
Guest
n/a Posts
Re: Nearly another 'how to tune my engine' question

Make sure you have a properly oiled air filter !!!
 


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