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newcarnage

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Im losing fuel pressure runs good goes real lean noticed that primer bulb empty ive replaced gas tank grommet in upgrade kit and little plug for gas cap. even changed fuel lines .Other question is everyone running standard CMR7H NGK or hotter plug
 
I had the exact issue, only I changed the carb, checked the intake, thought it might have been some issue with the ADA intake I just installed.


It takes a bit to setup the clunk in the tank and it can not be done with the stock fuel lines, they are too rigid. I was through it all too, it is frustrating, it almost makes you wonder if you know what you are doing ... I was just about stumped.


Definetly vent the fuel tank too it is a good idea.
 
ya, the tank just need to be vented. my mt is fine, but my tt needed a vent hole. tryed the upgraded one but was the same. at first i took the nipple thats inside the cap out, but it would leak fuel when i tipped it on its side on the bench, so i just put a small barbed end thru the cap with some fuel line


im running the standard plug
 
Ok ive searched around but no one has said how to vent the cap i see the brass nipple but do you leave the rubber parts in the cap
 
NEWCARNAGE said:
Ok ive searched around but no one has said how to vent the cap i see the brass nipple but do you leave the rubber parts in the cap
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I just did this to my 5B. I drilled a small hole in the cap from the outside and had an old 90 degree fuel line connector from one of my nitros. Threaded that into the cap and ran a piece of Tygon and attached a filter on the end of the line so it won't suck in dirt. What happens is the tank gets a vacuum from the engine burning the fuel and sometimes the cap (there are 4 parts to it) won't let air in around the rubber/plastic insert causing your engine to starve. Simply venting the cap like this allows it to suck air in but the vent gasket won't let fuel out in case of a roll over. It's an easy fix and yes, it had me stumped as well why my Baja would start to die at WOT. If you need I can take a pic and post it here.
 
NEWCARNAGE said:
Ok ive searched around but no one has said how to vent the cap i see the brass nipple but do you leave the rubber parts in the cap
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I have done them both way, the aircraft guys have access to the bass barbed fittings, I used a rubber gromet on my Redcat, all you realy need to do is drill a hole in the top of the fuel cap just small enough so the vent tube will fit in. Yes, remove all the guts from the cap.
 
Clubin said:
I have done them both way, the aircraft guys have access to the bass barbed fittings, I used a rubber gromet on my Redcat, all you realy need to do is drill a hole in the top of the fuel cap just small enough so the vent tube will fit in. Yes, remove all the guts from the cap.
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I left mine in. Does the mod you are talking about prevent fuel from coming out of the cap on a rollover? I can't have any fuel leaks because of where I store my RC's. I'd hate to wake in the middle of the night to a Bar-B-Que!
 
How is your carb set ?


1- 1/4 turns LOW END


1- 1/2 TURNS HIGH END


25 : 1 mixture


Sounds like your not getting fuel .......
 
Rammer said:
How is your carb set ?
1- 1/4 turns LOW END


1- 1/2 TURNS HIGH END


25 : 1 mixture


Sounds like your not getting fuel .......
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ya couse the tank cant breathe. as your using fuel it needs to be replaced with air. some tanks are fine and other have this problem. my first 5b was fine and my second was a pain couse of this..same with my ramps. you can easly tell if you pull the cap and it sucks air in


edit: and those settings are factory. its really rich. wont run well like that for long
 
Yes, that works,but the holes don't look very big ( like pin holes ) in the cap ?


Does not breath very well ? My baja 5b is the same , never had a problem with it. Mabe there is some other kind of air leak in the carb,or clunk in tank


is to low ? You need pressure to force gas to the carb .......
 
I just took off my gas cap to see if air would be sucked in. Found out the diaphram rubber part that goes into the cap is torn. Probably from screwing the cap down too tight. Anybody know where I can get an aftermarket one or the upgraded Rampage one like I had installed in it?
 
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