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carb settings wont start

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andrewn5998

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i got a revo 3.3 motor thats new, i had it running before but it got hot the other day and shut off, now i can't get it started. i tried adjusting the low fuel screw on the left side of the carb and was wondering where is a good place to set it at, how many turns out. the manual says to set it flush, i tried that and nothing, the motor has really good compression because my hand hurts like hell from trying to pull start it, any ideas?
 
Did you check the plug? A new 3.3 can ruin a plug quick, especially if it got hot. Flush is good, make sure the idle is ok and run it flush.
 
i have tried new plugs and still nothing, i can see fuel moving in the lines when i pull it but dont seem like its getting any, it never floods i keep checking it, i tried the exhaust mod i seen on here cutting 3/8 off the head pipe, would that cause anything?
 
That might give you a little more low end, but probably not. Try taking the line off the exhaust and blowing in it. Hold your throttle 1/4 to 1/2 open then blow until you see the fuel hit the carb, you should be able to hear it too. Then if it still doesn't run, hold your finger over the exhaust outlet and pull a couple times. Try that until it starts. Also make sure you have a fresh battery in your glow ignitor.
 
so far done all that and still nothing, i can see the fuel going to the carb, have 3 glo plug igniters i keep switching and recharging, and still nothing
 
I would say flood it then. You won't be able to pull it over easily when it floods. Next, remove the glow plug and pull it over quickly a few times while holding it upside-down. Now is a great time to burn the excess fuel off the plug and MAKE SURE it's glowing hot. Replace the plug, then try to start it, 3- 5 pulls only. Repeat the above mentioned process until it goes. Once it's flooded you can even try unhooking the fuel line while you pull it.....it'll start. Just unhook the exhaust line so the fuel doesn't run out of the tank when it starts.
 
can't do anything now until i get a new starter, my ez stripped a gear today so i put the pull start on then it broke so i fixed it, took me about 2 hrs with that stupid spring, then it just broke again so I'm done until i get a new electric start, hell with that pull start, i got blisters on about all my finger and my arms sore
 
Throw a glove on. Are you at factory setting on the hsn? Did you seal the engine? If the engine isn't sealed, it probably has an air leak, causing the heat issue. Make sure the head is tight and that everything is sealed up. Let your ignitors charge until they are slightly warm.
 
i havent sealed the engine yet while I'm waiting on a new starter i will try to get that done. I'm new to these what is hsn?
 
High speed needle=hsn. Use high-temp, sensor-safe copper rtv on the carb throat, back plate and header. Make sure the hsn housing is sealed too. That's where the fuel line attaches to the carb. Make sure there is no debris under the hsn. The needle and housing are very easy to strip out. Be careful. Never tighten the needle hard. Just turn it until it stops, then count 4 rotations out. That's the factory setting. Same with the housing. Very easy to strip.
 
Last edited:
Metalhead Matt said:
High speed needle=hsn. Use high-temp, sensor-safe copper rtv on the carb throat, back plate and header. Make sure the hsn housing is sealed too. That's where the fuel line attaches to the carb. Make sure there is no debris under the hsn. The needle and housing are very easy to strip out. Be careful. Never tighten the needle hard. Just turn it until it stops, then count 4 rotations out. That's the factory setting. Same with the housing. Very easy to strip.
Click to expand...

I coudln't have put it better!! i know from experience that the hsn housing will strip easily!!! so be EXTRA cautious!!!!
 
Flush with the housing. Remember that factory settings are just starting points. Until you have determined that the engine is sealed, adjusting the carb won't get you anywhere. And you definitely want to avoid over-heating the engine. Air leaks cause a lean condition, which almost always leads to temp spikes.
 
how much fuel line is required? on mine the guy had about 20 inches of line that looks like way too much to me.
 
It doesn't really matter how much fuel line you have, a little long is good, but 20 inches seems like a bit much. Revos come with quite a bit when they're new.
 
just got done sealing my engine and have a couple of questions. how do i get the connecting rod off of the crank? the book says to pull with needle nose pliers i tried that and it came off a little but then stopped i tried pulling but was afraid of breaking something so i stopped. and i couldnt seal my hsn because it turns extremely hard and was afraid of breaking it so i just removed the whole thing by the nut and sealed under it and where the gas goes in the carb, how could i tell when the hsn is all the way in so i can get it back to factory setting I'm afraid of breaking it since it turns so hard?
 
You have to get the sleeve out, it's not necessary for sealing an engine. Also just hold the hsn nut and turn the needle with a screwdriver. Do not seal in there, you sealed the right part.
 
so the needle turns that hard how do i know when its all the way in so i can turn it out 4 turns because i know i got it moved?
 

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