The Complete Beginners Guide To RC's

Jam Racing 1

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Airplane and surface engines are way different most of the plane engines do not get throttled like our car/truck engines do, if seeing bubbles in the fuel line it is telling you there is air getting in somewhere...
I know it is a bit of work but you will thank yourself after it is done.......
 

seeingeyegod

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I'm not really willing to take apart the entire engine but I am thinking I must have a leak in the carb. When priming I easily get fuel to the engine with no bubbles, but as soon as I actually try to start, a bunch of bubbles appear. I took the one hex screw out at the base of the carb which appears to be the only thing holding it in, but it didn't seem to want to budge. Maybe it is sealed/glued in? Perhaps it is my fuel inlet where I removed and replaced the needle which is leaking
 

Jam Racing 1

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I'm not really willing to take apart the entire engine but I am thinking I must have a leak in the carb. When priming I easily get fuel to the engine with no bubbles, but as soon as I actually try to start, a bunch of bubbles appear. I took the one hex screw out at the base of the carb which appears to be the only thing holding it in, but it didn't seem to want to budge. Maybe it is sealed/glued in? Perhaps it is my fuel inlet where I removed and replaced the needle which is leaking

It is not difficult to take it apart and clean, seal and put back together... as for the carb bolt you have to tap it with the nut still on too loosen it up for removal... it is on a taper and just takes a bit of finesse, the fuel barrel has 2 washers on it and if tight enough it should seal..., if you have had plane engines then this one outta be pretty easy....

you have to remember these :ercm: are mass produced in china and the tolerances do change from engine to engine.....
Go get some permatex o2 safe copper seal and a tube of green slime from the hobby shop, anyone who sells associated RC stuff outta have the green slime, just do it to save yourself a bunch of blisters and headache :DOH:
 

JVT73

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I'm not really willing to take apart the entire engine but I am thinking I must have a leak in the carb. When priming I easily get fuel to the engine with no bubbles, but as soon as I actually try to start, a bunch of bubbles appear. I took the one hex screw out at the base of the carb which appears to be the only thing holding it in, but it didn't seem to want to budge. Maybe it is sealed/glued in? Perhaps it is my fuel inlet where I removed and replaced the needle which is leaking
Something sounds way wrong, pic's of your rig would be great. The pictures help other members with years of knowledge sort out your problems. No pic's leads to the question game...like are you running a primer bulb? No/yes? Are you running a inline fuel filter? No/yes? Air can be getting in from lots of places. Pictures save time and a million questions.
 

seeingeyegod

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Something sounds way wrong, pic's of your rig would be great. The pictures help other members with years of knowledge sort out your problems. No pic's leads to the question game...like are you running a primer bulb? No/yes? Are you running a inline fuel filter? No/yes? Air can be getting in from lots of places. Pictures save time and a million questions.
Well I think I've now fixed the leak, I screwed my carb fuel inlet down more and they (bubbles) went away. I'm thinking my problem is inconsistent glow now. I'm using a D battery powered one and I realized it sometimes loses connection to the plug while I was testing it. When it moves around as I crank it's probably losing connection. No fuel filter, no primer bulb. I don't think pics would help really, I have nothing questionable to take a picture of. This is a brand new stock k4.6 on a brand new Savage X SS, it looks exactly like one of those. All the needles are at factory settings.
 

X

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I'm thinking my problem is inconsistent glow now. I'm using a D battery powered one and I realized it sometimes loses connection to the plug while I was testing it. When it moves around as I crank it's probably losing connection.
I assume this is a glow plug igniter that you've had for a while? I find I need to clean the contact (portion that touches the glow plug) from time to time. I just use a q-tip.
 

JVT73

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Well I think I've now fixed the leak, I screwed my carb fuel inlet down more and they (bubbles) went away. I'm thinking my problem is inconsistent glow now. I'm using a D battery powered one and I realized it sometimes loses connection to the plug while I was testing it. When it moves around as I crank it's probably losing connection. No fuel filter, no primer bulb. I don't think pics would help really, I have nothing questionable to take a picture of. This is a brand new stock k4.6 on a brand new Savage X SS, it looks exactly like one of those. All the needles are at factory settings.
I'm still not understanding how air is getting from your carb and into the fuel line coming from your fuel tank? Unless it can flow in both direction at the same time. I'm thinking your new SS is doing the same thing mine did, which is as the clunk(stone) filter in the tank was agitated by vibration, little air bubbles would be released until it was completely saturated and like wise for my inline filter. Took about three tanks to clear up.
 

seeingeyegod

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I'm still not understanding how air is getting from your carb and into the fuel line coming from your fuel tank? Unless it can flow in both direction at the same time. I'm thinking your new SS is doing the same thing mine did, which is as the clunk(stone) filter in the tank was agitated by vibration, little air bubbles would be released until it was completely saturated and like wise for my inline filter. Took about three tanks to clear up.
Pretty sure it was a leak between the needle valve base and the crankshaft. That alone might not have been the prob. Update though, i got her running! It was the glow igniter. Cleaned the contact and put in a new batt and got it got much brighter! Thanks for the suggestion from other poster. Ran a fyll tank at about half throttle. Startes getting a bit stronger by the end. Ran over some rough ground and it soaked the bumps up really well. Steering feels really nice also, good handling!
 

seeingeyegod

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Okay so I'm an idiot, after saying how I'm gonna follow the manual instructions for break in, I just realized I read the instructions wrong. I thought it said run the 1st tank at 1/4 throttle, when really it said start at 1/4 throttle and run the first tank at idle! So now I'm afraid I screwed up the initial break in. so far I've run approx 3 tanks. 1 at partial idle and mostly 1/4 throttle with wheels off the ground, and 2 at mostly 50% throttle with periods of idle and some in between driving around in circles and figure 8s. I have adjusted the needle to be slightly leaner than factory (maybe 2/8ths of a turn in) because otherwise it would bog down and quit as I approached 50%, and acceleration/power overall was extremely weak (which is to be expect when super rich and new). The whole time I'm getting lots of smoke so obviously it's still quite rich. I'm thinking I should now just let it idle through an entire tank before putting it on it's wheels again and then probably do at least one more tank at less than 50%. I was at least able to do some short bursts of full throttle without it stalling near the end of the last tank.
 
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Jam Racing 1

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I always do my breaking in running on the ground... having the wheels off the ground can stress the engine in my opinion....
I run a few tanks just messing around at part throttle and after I tune for running and get after it.......

So keep after it and it will come around, better to go slow and let the engine wear in a bit so it will last and run right....
 
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