R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Nitro On-Road > Onroad Nitro Engine Zone

Reply
 
Thread Tools Search this Thread
Old 05-23-2007, 11:24 AM   #16
Tech Elite
 
stefan's Avatar
 
Join Date: Aug 2001
Location: Bavaria, Germany
Posts: 3,273
Send a message via AIM to stefan
Default

Quote:
Originally Posted by areal
Hi Stefan,

If the engine is spraying fuel out of the carb, check if your starter box is rotating in the correct direction.

I hope this helps!
Uumh, no!

It start every other engine the right way.
stefan is offline   Reply With Quote
Old 05-23-2007, 11:27 AM   #17
Tech Elite
 
stefan's Avatar
 
Join Date: Aug 2001
Location: Bavaria, Germany
Posts: 3,273
Send a message via AIM to stefan
Default

Quote:
Originally Posted by RayJ
I have experienced the same phenomenon with my JL Red Dot. I too tried everything from compression change, pipe change, carb change and couldn't figure out what it was. My front bearing is also in great shape with no signs of any leakage at all.

I also run in Toledo where air temps and barometric pressures change dramatically and we're at 600 ft above sea level.

What Massive says makes sense about the front bearing and it's effects. The motor just doesn't seem to want to draw fuel after it warms up(two to three minutes of warm-up) Each time the motor has done it I had to richen it up about three hours on the top end. This only worked sometimes. Then I changed my clutch and bottom end tuning. I really tightened my clutch down to the point where it was slipping, and then backed it off abit so that it wasn't slipping but kept the motor up in the rpm ranges before engaging. I also richened up the bottom end about two to three hours so that it seemed fat and not where I would normally run any other engine. Running the motor that way I could lean the top end where I wanted it, and it would come into the pits and immediately idle down. It would then leave a healthy trail of smoke leaving the pits initially but would be okay on the track with some smoke and good hard acceleration. The motor has a tendency to really lean out alot after two to three minutes of hard running so a good warm-up before a qualifier is really important.

In conclusion.........running the bottom fatter then normal.........tightening down the clutch a bunch stopped my lean bogging. It sems the motor with a lean bottom and lean top starves for fuel, and the rich bottom seems to help a ton. Hope this helps.

Alright, I have been hearing this solution / theory a lot know, so I guess it's time to try it out.

Maybe I'll try to change the taper of the low speed needle as well. Somebody told me that they are very blunt and actually act "digital". It's either on or off.

Thanks buddy, keep 'em coming. We'll get the sucker, sooner or later
stefan is offline   Reply With Quote
Old 05-23-2007, 04:59 PM   #18
Tech Regular
 
RayJ's Avatar
 
Join Date: May 2003
Posts: 445
Default Needle taper

Stefan.........I probably wouldn't bother with the taper of the needle. Just run it rich on the bottom.........Tight clutch...........and tune the HSN for top end performance. Your lean bogging will go away. I spent a whole afternoon figuring that out. I believe my low speed needle is 8 turns out. I know you will be tempted to lean on the lsn as all engine tuners want to......... but resist the temptation........It will sound fat........and it wil be......but on the track it will be fine. The other big plus..............is when the others are struggling to make mileage............you won't!
RayJ is offline   Reply With Quote
Old 05-25-2007, 08:44 AM   #19
Tech Elite
 
EdwardN's Avatar
 
Join Date: May 2003
Location: SoCal
Posts: 2,144
Trader Rating: 1 (100%+)
Default

Pipe too short
__________________
DISCLAIMER: Since 90% of my posts may be BS, and since my posts may be either insanely idiotic, incoherent, and/or not even close to a rational thought, please accord my posts no more than 10% of credibility.
EdwardN is offline   Reply With Quote
Old 05-25-2007, 09:04 AM   #20
Tech Master
 
tl2111's Avatar
 
Join Date: Mar 2002
Location: Love 1/8th
Posts: 1,561
Trader Rating: 21 (100%+)
Send a message via MSN to tl2111
Default

Quote:
Originally Posted by EdwardN
Pipe too short
where have you been Ed??
__________________
*Tourer**Futaba***SpeedPassion
*F1**4PX***TORO
*12th**4PX***TORO
*8th**4PX***OS Speed XZ-R
*10th**4PX***OS Speed XZ
tl2111 is offline   Reply With Quote
Old 05-25-2007, 09:26 AM   #21
Tech Elite
 
stefan's Avatar
 
Join Date: Aug 2001
Location: Bavaria, Germany
Posts: 3,273
Send a message via AIM to stefan
Default

Quote:
Originally Posted by EdwardN
Pipe too short
Original Picco 2607 pipe, as recommended by the manufacturer and as run by most people who have this engine.

Hi Edward, long time no speak.

How are you?
stefan is offline   Reply With Quote
Old 05-25-2007, 10:08 AM   #22
Tech Elite
 
EdwardN's Avatar
 
Join Date: May 2003
Location: SoCal
Posts: 2,144
Trader Rating: 1 (100%+)
Default

Quote:
Originally Posted by tl2111
where have you been Ed??
Hi Tomy it is very long story and now it is all over-I am back
__________________
DISCLAIMER: Since 90% of my posts may be BS, and since my posts may be either insanely idiotic, incoherent, and/or not even close to a rational thought, please accord my posts no more than 10% of credibility.
EdwardN is offline   Reply With Quote
Old 05-25-2007, 10:12 AM   #23
Tech Elite
 
EdwardN's Avatar
 
Join Date: May 2003
Location: SoCal
Posts: 2,144
Trader Rating: 1 (100%+)
Default

Quote:
Originally Posted by stefan
Hi Edward, long time no speak.

How are you?
Hi Stefan.
I am OK, feel different now. I am not working for Axial any more, got another job.
__________________
DISCLAIMER: Since 90% of my posts may be BS, and since my posts may be either insanely idiotic, incoherent, and/or not even close to a rational thought, please accord my posts no more than 10% of credibility.
EdwardN is offline   Reply With Quote
Old 05-25-2007, 11:08 AM   #24
Tech Master
 
tl2111's Avatar
 
Join Date: Mar 2002
Location: Love 1/8th
Posts: 1,561
Trader Rating: 21 (100%+)
Send a message via MSN to tl2111
Default

Quote:
Originally Posted by EdwardN
Hi Stefan.
I am OK, feel different now. I am not working for Axial any more, got another job.
Wow this is huge Edward, no more Axial????
__________________
*Tourer**Futaba***SpeedPassion
*F1**4PX***TORO
*12th**4PX***TORO
*8th**4PX***OS Speed XZ-R
*10th**4PX***OS Speed XZ
tl2111 is offline   Reply With Quote
Old 05-25-2007, 01:40 PM   #25
Tech Elite
 
Corse-R's Avatar
 
Join Date: Aug 2001
Location: Madrid (Spain)
Posts: 2,121
Default

Quote:
Originally Posted by EdwardN
Hi Tomy it is very long story and now it is all over-I am back
Excellent news!
__________________
Cheers,
Corse-R
---
[quote=MugenDrew;2684554]BATTERIES are for FLASH LIGHTS, gasoline is for cleanin parts, alcohol is for me to drink and well NITRO...everybody know thats for racing.[/quote] :D:D:D
Corse-R is offline   Reply With Quote
Old 05-25-2007, 03:20 PM   #26
Tech Elite
 
stefan's Avatar
 
Join Date: Aug 2001
Location: Bavaria, Germany
Posts: 3,273
Send a message via AIM to stefan
Default

Quote:
Originally Posted by EdwardN
Hi Stefan.
I am OK, feel different now. I am not working for Axial any more, got another job.
Hi Edward, you say you feel different now. I hope better?

I didn't even know that you worked full time for Axial. Did you quit your maintenance job that you did before?
stefan is offline   Reply With Quote
Old 05-25-2007, 05:35 PM   #27
Tech Elite
 
EdwardN's Avatar
 
Join Date: May 2003
Location: SoCal
Posts: 2,144
Trader Rating: 1 (100%+)
Default

Quote:
Originally Posted by stefan
Hi Edward, you say you feel different now. I hope better?

I didn't even know that you worked full time for Axial. Did you quit your maintenance job that you did before?
I didn't quit mainetnance manager position-last year while I was in Fl on Winternats company went out of business, after I came back I was offered to work for Axial. Now I am no longer work for Axial.
__________________
DISCLAIMER: Since 90% of my posts may be BS, and since my posts may be either insanely idiotic, incoherent, and/or not even close to a rational thought, please accord my posts no more than 10% of credibility.
EdwardN is offline   Reply With Quote
Old 05-25-2007, 05:36 PM   #28
Tech Elite
 
EdwardN's Avatar
 
Join Date: May 2003
Location: SoCal
Posts: 2,144
Trader Rating: 1 (100%+)
Default

Quote:
Originally Posted by Corse-R
Excellent news!
Thanks a lot Alfonso.
How are you been?
__________________
DISCLAIMER: Since 90% of my posts may be BS, and since my posts may be either insanely idiotic, incoherent, and/or not even close to a rational thought, please accord my posts no more than 10% of credibility.
EdwardN is offline   Reply With Quote
Old 05-25-2007, 05:53 PM   #29
Tech Master
 
MassiveMods's Avatar
 
Join Date: Jan 2006
Location: Sydney
Posts: 1,977
Default

Quote:
Originally Posted by stefan
Hi MassiveMods, thanks for the hint. Could this also cause the engine spraying fuel out of the carb?

Cheers.

I dbout it , sounds like a hydro lock when flooded sending the piton back the opposite way , the only place the pressure can escape is out through the carb..

I could be wrong..

Ok heres another theory , Do you have an MSN on any of these carbs ? if so feel how loose it is .. if its not tight as a squirrels nuts then you will have tune probs. Take out the MSN and cover the end seal with plummers tape, make sure you only cover the very end of the seal, screw this back in and see what happens..

the problem you are encountering in my opinion is tuning the engine from a full tank. If you were to tune the engine from half to 3/4 empty you would have a better average tune. remember the tuning on these things changes as the tank pressure changes. When you are at half tank you have an average pressure. When you tune from a full tank you have plenty of fuel pressure, forcing fuel into the carb, you lean it to suit, but when the pressure drops you have less fuel = lean engine. this can over heat it to the point where the power dropps off out of corners when the lsn is too lean or it wont go hard till you hit half way down the straight, meaning too lean on HSN.. When this is left for too long you will pre maturely wear the piston on the exhaust side and cause blow by .. then all sorts of other problems occour.. and tuning isnt gonna fix it .. When its cold it will seem like its got heaps of pop , but at temp the flat spot on the piston will allow compression to escape and stoppig the pupm effect of the engine. This leans it out even further cos thers no suction to draw the correct amount of fuel on the down stroke ..

So best way to fix this is to tune it right from the start , if once you got the tune right and one day its all out .. dont try to fix it with tuning , look around the engine for a cause or strip down the engine to see why its changed.. Unless you have a crappy carb with loose needles you should only ever have to make very tiny changes to tuning if any .. I tend to get a tune on an engine then leave it .. dont be tempted to lean it off when you start it cos it seems rich... it takes half a tank to get to operating temp..



Hope this helps !

Cheers mM
__________________
Engine development manager Rifling Pty Ltd. Nitro fuel designer : Neo + World record title holder 2012 Austalian Nationals 147.6 KPH , 1 st 2 nd and TQ Australian National Buggy titles 2012. Victorian State title 2012 Neo + , South Australian state title ON and Off Road 1/8 2012 Neo + :-) QLD State Titles 2012 1st buggy & trruggy + TQ Neo + MG66 RX7 1st Sportsman Class Truggy QLD State Titles 2012 !! Nitro Addicts Australia . com
MassiveMods is offline   Reply With Quote
Old 06-12-2007, 12:46 AM   #30
Tech Apprentice
 
Morgan Johns's Avatar
 
Join Date: Jan 2006
Location: Mississauga
Posts: 74
Default

Hello All,

I have recently posted in the Serpent 720 thread about a similar issue. My motor is beautiful for 2-3minutes then slpowly looses power to the point its like running a blackcan. This happened in both motors I tried(Mention they were both working perfect fro 3weeks then all of a sudden this happened)

I am using the Mega ZX12 Race and Mega MF, both had the same issue after my 3rd qualifier when the issue happened the motor just lost power. I took the motor apart (both) cleaned and everything to inspect but there were no leaks or anything no unusual wear nothing. I then took the tank to a air compressor and blew it into the pressure nipple. turns out almost all of the air was esacping through the cap, I applied a little bit of pressure to the cap, and I mean alittle and voilla it all came out the fuel resevoir.

It may not seem noticable but try it(if you have an air compressor, rember these engines at high RPM are forcing through alot of air. I have read elsewhere people using fuel filters on the pressure line to decrease air pressure and volume going into the tank. I will try this this weekend with a new cap, spring and seal of course. Hopefully this will solve the issue.

Also I have heard wind that using the wrong glow plug will cause this isue, but I dont know about that as I was using a NR 7Cold on a day with medium humidity and about 24-27deg celcius which everyone else was running and both motors experienced the same issue.

It has to be a result of air leakage, anyone else have other thoughts?
Morgan Johns is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Engine problems cherokee Nitro Off-Road 2 04-18-2008 11:24 AM
Mysterious Glitching Program TEM Electric On-Road 5 02-11-2007 04:53 PM
Engine Problems LosiSuperTruck Monster Trucks 4 10-07-2005 06:40 AM
Hara's mysterious battery charging aid EddieO Electric On-Road 170 08-04-2004 11:05 AM
Engine problems nanjoutai Nitro On-Road 4 06-09-2003 10:20 AM



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 07:20 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net