Win a Proline body of your choice: RCNT Fantasy Football League!!

Go Back   RCNitroTalk > R/C Forums > Traxxas T-Maxx

Air bubbles building up in fuel feed line.

Discussion in Traxxas T-Maxx forum, started by svecobrar.

Post Reply
Thread Tools
Unread 5-07-2012, 10:19 PM   #1
svecobrar
RCNT Member
 
Join Date: Mar 2012
Posts: 25
Trader Feedback: (0)
Mentioned: 0 Post(s)
Air bubbles building up in fuel feed line.

Hey guys I need help. I have classic tmaxx with a 2.5, and the truck runs pretty good but it runs a bit too hot and i've tried sealing the engine and all thr basic stuff. One thing I have noticed is that the fuel feed line is constantly full of air bubbles.

Ive put a brand new gas tank in it and I've tried a few different fuel line routings to try and keep the fuel as cool as possible but I feel that the heat is still getting to the fuel and causing vapor lock.

I have three other nitro monster trucks so im not a beginner by any means but am not a expert either.

Thanks in advance
Status: Offline
 
Quote
Unread 5-07-2012, 11:25 PM   #2
REVO-5309
Hardcore RCNT User
 
REVO-5309's Avatar
 
Join Date: Sep 2011
Location: Australia
Posts: 1,276
Experience: I am new to RC
Trader Feedback: (0)
Mentioned: 1 Post(s)
there isn't enough back pressure going through the exhaust to push the fuel through the line.... check the header seal
Status: Offline
 
Quote
Unread 5-08-2012, 4:18 AM   #3
2revo1maxx
Hardcore RCNT User
 
2revo1maxx's Avatar
 
Join Date: Nov 2009
Location: Uzbekistan
Posts: 4,647
Experience: I am an experienced RC driver
Trader Feedback: (0)
Mentioned: 4 Post(s)
Is it a brand new tank? Are all the screws in it and tight? A loose or missing screw can cause foaming.
Status: Offline
 
Quote
Unread 5-08-2012, 6:23 AM   #4
Phins Fan
Hardcore RCNT User
 
Phins Fan's Avatar
 
Join Date: Aug 2011
Location: Chester, MA
Posts: 2,103
Experience: I am an experienced RC driver
Trader Feedback: (7)
Mentioned: 8 Post(s)
Do you have anything else in the fueline like a filter or a finned cooler? Those extra breaks in the line can cause airleaks as well.
Status: Offline
 
Quote
Unread 5-09-2012, 1:17 AM   #5
svecobrar
RCNT Member
 
Join Date: Mar 2012
Posts: 25
Trader Feedback: (0)
Mentioned: 0 Post(s)
I don't have anything else in the fuel tank or on the line. I guess my next step would be to check the header seal. Can I test it for leaks with soap and water while it runs?

Also does the stock pipe on the tmaxx make it sound like the idle is high compared to, lets say a revos? My stock piston and sleeve are out getting repinched so I put my revo 2.5r in it for the time being, same fuel line systems by the way, and it seems like the 2.5r idles a lot higher in the tmaxx then in the revo.

Thanks again.
Status: Offline
 
Quote
Unread 5-09-2012, 2:17 AM   #6
REVO-5309
Hardcore RCNT User
 
REVO-5309's Avatar
 
Join Date: Sep 2011
Location: Australia
Posts: 1,276
Experience: I am new to RC
Trader Feedback: (0)
Mentioned: 1 Post(s)
just blow into the exhaust pipe. if pressure doesn't build up then there is a leak somewhere. if you blow into it and when you stop the air rushes back out then its tight...
Status: Offline
 
Quote
Unread 5-09-2012, 4:26 AM   #7
2revo1maxx
Hardcore RCNT User
 
2revo1maxx's Avatar
 
Join Date: Nov 2009
Location: Uzbekistan
Posts: 4,647
Experience: I am an experienced RC driver
Trader Feedback: (0)
Mentioned: 4 Post(s)
So the screws are all in and tight then?
Status: Offline
 
Quote
Unread 5-09-2012, 4:44 AM   #8
svecobrar
RCNT Member
 
Join Date: Mar 2012
Posts: 25
Trader Feedback: (0)
Mentioned: 0 Post(s)
Ya the screws are in and tight. Its alot easier putting the tmaxx header on compared to.the revo one so I know its on there good. Ill be checking the exhaust for leaks in the morning.

Status: Offline
 
Quote
Unread 5-09-2012, 4:14 PM   #9
2revo1maxx
Hardcore RCNT User
 
2revo1maxx's Avatar
 
Join Date: Nov 2009
Location: Uzbekistan
Posts: 4,647
Experience: I am an experienced RC driver
Trader Feedback: (0)
Mentioned: 4 Post(s)
I meant the fuel tank, make sure it's secure.
Status: Offline
 
Quote
Unread 5-09-2012, 6:58 PM   #10
svecobrar
RCNT Member
 
Join Date: Mar 2012
Posts: 25
Trader Feedback: (0)
Mentioned: 0 Post(s)
Ya the fuel tanks secure, i've removed it a bunch of times and its solid. I'm going to try the suggestions about the header gasket tonight or tomorrow, whenever I get my parts in from rcrenew and amain so I can do everything at once.
Status: Offline
 
Quote
Unread 5-13-2012, 11:12 PM   #11
svecobrar
RCNT Member
 
Join Date: Mar 2012
Posts: 25
Trader Feedback: (0)
Mentioned: 0 Post(s)
I replaced the exhaust to fuel tank fuel line and it helped with the air bubbles but they were definitely still happening and causing some problems although the idle went down very noticeably. I didn't have time to swap out the tank as it was because I was racing my buddy's lrp .30 savage x and didn't want any down time.

I did check the exhaust for leaks and none were found. And I did notice that when I fill the tank full I get fuel that goes into the pipe to tank line. Is that normal?
Status: Offline
 
Quote
Unread 5-13-2012, 11:43 PM   #12
Pope
RCNT Talkaholic
 
Pope's Avatar
 
Join Date: May 2012
Posts: 263
Trader Feedback: (0)
Mentioned: 0 Post(s)
Replace all fuel lines and check all seals on header and fuel tank. You may have a clogged in tank filter and need to replace the tank.
Status: Offline
 
Quote
Unread 5-14-2012, 4:35 AM   #13
2revo1maxx
Hardcore RCNT User
 
2revo1maxx's Avatar
 
Join Date: Nov 2009
Location: Uzbekistan
Posts: 4,647
Experience: I am an experienced RC driver
Trader Feedback: (0)
Mentioned: 4 Post(s)
Just get a new tank, it obvious that your problem is with that.
Status: Offline
 
Quote
Unread 5-14-2012, 9:00 PM   #14
svecobrar
RCNT Member
 
Join Date: Mar 2012
Posts: 25
Trader Feedback: (0)
Mentioned: 0 Post(s)
thanks i'm going to swap it after I swap the springs on the mgt 8.0 I just bought.
Status: Offline
 
Quote
Unread 5-23-2012, 3:07 AM   #15
svecobrar
RCNT Member
 
Join Date: Mar 2012
Posts: 25
Trader Feedback: (0)
Mentioned: 0 Post(s)
swapped tanks but still having the same problems. The car runs pretty good with the newly repinched motor but it tends to run hot so I bought a golden horizons cooling head and we'll see how that goes.
Status: Offline
 
Quote
Post Reply

Share This Post


Thread Tools

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

Forum Jump

All times are GMT -5. The time now is 6:39 PM.
Copyright © 2008-2011 RCNitroTalk, All Rights Reserved.
Powered by vBulletin®, Copyright ©2000 - 2009, Jelsoft Enterprises Ltd.