R/C Tech Forums

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

Reply
 
Thread Tools Search this Thread
Old 12-31-2003, 04:54 PM   #1
Tech Initiate
 
Join Date: Dec 2003
Posts: 45
Post Engine Temperature CHANGES with fuel level?

I noticed with the GS21R noob engine, the temperature of the engine increases as the fuel is used up in the fuel tank.

At the current setting - it starts (after running 2 tanks already - so the engine is warmed up) at the low 190F when the tank is full then goes as high as 250F just as the tank is about to run out of fuel.

Anyone else notice this with their engines? Race engine or not.

I'd assume that the engine ran rich at FULL fuel level as the *head* of the fuel liquid gives the engine that certain pressure. As the fuel is used up, the pressure head drops - causing the engine to run leaner - thus in effect - raising the temperature of the engine.

Comments?


NOTE: There is NO leak whatsoever on the fuel tubing (its new tubing) and all fuel inlet outlet from the tank to the engine and to the exhaust is snug.
gonsped is offline   Reply With Quote
Old 12-31-2003, 05:33 PM   #2
Tech Apprentice
 
Join Date: Dec 2002
Posts: 74
Default

I don't have a .21 engine at the present time but from my expereance nitro engines range from 240f to about 270f depending on the engine and the tuning. If your engine is tuned coeectly you should be running at about 220f after a one minute run. This should go up the longer the engine is run until you get up to about 250F to 270F. I have two .12 nova engines and they run at about 260 to 270F. You should tune for performance not temperature. If you are getting good power at the high and low end, I would not worry about it.
nitro dipstick is offline   Reply With Quote
Old 12-31-2003, 06:40 PM   #3
Tech Initiate
 
Join Date: Dec 2003
Posts: 45
Default

What is the max. temp limit (in F) in their engine everyone tries to go below?

I read 270F should be as high as you want to go.
gonsped is offline   Reply With Quote
Old 01-02-2004, 10:11 AM   #4
Tech Master
 
Ah10's Avatar
R/C Tech Charter Subscriber
 
Join Date: Sep 2001
Location: Pasadena/Southern California
Posts: 1,370
Send a message via ICQ to Ah10 Send a message via AIM to Ah10 Send a message via Yahoo to Ah10
Default Re: Engine Temperature CHANGES with fuel level?

Quote:
Originally posted by gonsped
I noticed with the GS21R noob engine, the temperature of the engine increases as the fuel is used up in the fuel tank.

At the current setting - it starts (after running 2 tanks already - so the engine is warmed up) at the low 190F when the tank is full then goes as high as 250F just as the tank is about to run out of fuel.

Anyone else notice this with their engines? Race engine or not.

I'd assume that the engine ran rich at FULL fuel level as the *head* of the fuel liquid gives the engine that certain pressure. As the fuel is used up, the pressure head drops - causing the engine to run leaner - thus in effect - raising the temperature of the engine.

Comments?

NOTE: There is NO leak whatsoever on the fuel tubing (its new tubing) and all fuel inlet outlet from the tank to the engine and to the exhaust is snug.
your bottom end needle(idle fuel mixture adjustment) might be too lean. Meaning even when your high speed needle is rich enough but when you are off throttle you will be running lean and makes your motor running hotter and hotter!
Granted when you are out of fuel the engine temp will rise up but not that big of a gap, from 190 to 250.

On 0.21 size onroad motor you dont want to run it hotter then 210 on pratice day, 230 on race day! if you run it hotter expect the life of the engine will become shorter!
Ah10 is offline   Reply With Quote
Old 01-02-2004, 10:24 AM   #5
Tech Adept
 
The Sleeper's Avatar
 
Join Date: Aug 2003
Location: West Virginia
Posts: 123
Default Re: Engine Temperature CHANGES with fuel level?

Quote:
Originally posted by gonsped
At the current setting - it starts (after running 2 tanks already - so the engine is warmed up) at the low 190F when the tank is full then goes as high as 250F just as the tank is about to run out of fuel.
Alittle more info would be helpful.

Are you filling your tank then starting the engine and just letting it idle? If so, then your low end needle is too lean.

Or, are you filling your tank then starting your engine and taking its' temperature before running your car around the track? If so, then you're not doing a good comparison between a full tank and a near empty tank.
The Sleeper is offline   Reply With Quote
Old 01-02-2004, 03:56 PM   #6
afm
Tech Master
 
afm's Avatar
 
Join Date: Nov 2003
Location: lima-peru
Posts: 1,807
Default

Also keep in mind that the longer the fuel pressure line coming out from the pipe, the leaner you can make your engine at mid range, so that fine tuning can also make the difference in temp. cahnges between full and low tank.
AFM
afm is offline   Reply With Quote
Old 01-02-2004, 07:04 PM   #7
Tech Master
 
Rapid Roy's Avatar
 
Join Date: Oct 2002
Location: L.A. (Rowland Hts)
Posts: 1,531
Default

Having the temp gradually rise is a normal thing. If you look at Ron Paris' web site, he doesn't think that an engine is warmed up until the chassis is hot as well. This happens with the top racers when they flame out in the long mains.
Rapid Roy is offline   Reply With Quote
Old 01-04-2004, 10:08 AM   #8
Tech Elite
 
popsracer's Avatar
 
Join Date: Oct 2002
Location: "Hot, Sunny Southern California"
Posts: 3,120
Default Engine Temperature CHANGES with fuel level?

gonsped;

This is common in ALL Vehicles, but even more so in Trucks with large fuel tanks. A very long pressure line from the Pipe can also exacerbate the problem.

The solution is to tune your engine at about 1/2 a tank and fully warmed up (200 F). Also try making the pressure line to the tank a little shorter if possible.
popsracer is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Fuel Temperature Ramiel Nitro On-Road 9 06-22-2008 07:34 PM
Engine temperature steponit! Malaysian R/C Racers 27 12-14-2006 01:50 AM
engine temperature any one?? downunder23 Electric Off-Road 16 10-02-2006 07:51 AM
Engine Temperature adsl Onroad Nitro Engine Zone 2 11-24-2004 10:02 AM
Engine Tune MAJORLY effected by Tank fuel level V-One S Onroad Nitro Engine Zone 10 04-12-2004 01:42 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 07:02 AM.


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