cemeb4dk

Why does my savage run great for only 1/2 then die and then can't restart til it completely cools. I don't even have a gallon of gas thru it.

I've tried running a longer fuel line. I have 2 fuel filters one to carburator and one one exhaust return.

I've tried to run it richer(HSN & LSN and combinations of both), because i know as the tank level lowers the truck automatically runs leaner.

Should i try the idle adjustment screw. i've tried playing with the idle on the transmitter with no success.

I'm only 2 weeks into this hobby, so as i'm learning quickly thanks to my savage, but i don't have all the answers. so if anyone is having or has had this problem please share your pain or how you fixed the problem. Because man i love this truck i just want more time than a half of tank.

Thanks for any and all suggestions..

grampi

Someone mentioned earlier that many of the Savages have been coming form the factory with fuel tank problems. You may have one of them. You might try doing a search to see if you can find that thread. I don't remember the title of it. Good luck.

redbluffwingnut

My Feedback: (2)

check to see of you have a pinhole in the fuel inside the tank , bench run and watch fuel in the line and see if bubbles apear right before it quits

cemeb4dk

Ok redbluff i will check, but would that prevent it from restarting and wouldn't i see leakage.

Thanks for the info and keep it coming i have to solve this issue, and will search for the other thread.

Avalanche

Get rid of the fuel filter on the exhaust side, its not doing anthing but potentially reducing fuel pressure. Return your fuel line to its stock configuration and reset the carb needles to factory specs. It sounds like you are overheating the engine. Once you get it running, look fo air bubbles in the the supply line, if you have them it may be that the primer is leaking.

fourwheeler

It definately sounds as if you are running too lean. This situation compounds itself with 1/2 or less in the tank. Try setting your needles with a little less than half in the tank.

new72Savage

I am having the sam e problem. Suposedly there are a couple of tank mods than can relieve the problem (see savage-central). one uses a header tank and one uses a one way valve. I find pinching the fule line when its hot, then rev the controller once it fires. U are right this is very frustrating. I have quite figured it out yet. turn up the idle and leaning the LSN does make it easier to get it fired again. Soon i will be doing a tank mod.

Based on observation i think the whole problem is that the pick is lower than the carb center line. when the tank is full, gravity pushes on the fuel. At about half a tank the carb center line is even with the fule level. No more gravity, now it has to suck. Teh one way value helps by maintain pressure into the tank from the exhaust (it goes in the scavange line). The header tank solves the prob by repositioning the tank pick up above the carb center line (header tanks are used in heli's). I havent tried either yet, but both make sense based on my observations regarding the problem.

new72Savage

Rigth now i am trying to figure out an easy way to raise the tank mount to solve the problem. And no the savage hates to start when its hot. SAve ur sweat and have a cig break when it stalls...then go at it.

Avalanche

The pressure line from the exhaust keeps the tank positively charged and provides fuel under pressure. The Savage .21 is a very easy starting engine, you have the carb set wrong or the tank isnt sealed properly. Make sure the line from the exhaust is secure, the cap is properly seated on the tank and the feed line isnt pinched. It may also be a good idea to pull the fuel filter until you get things straightened out and running right.

cemeb4dk

Round 2.

here is the latest.

1- replaced both fuel lines with no filters attached. check lines for air bubbles. none seen

2- set carb at factory settings.

Results: Still cannot keep running. So i haven't even got back to the 1/2 tank issue. before resetting carb setting tried leaning and richening with no success. Just seems like no getting fuel.

Question if i push down the primer multiple times should i be able to get fuel all the way thru the line into carb. Because i cannot. only gets about half way.

When i first got the truck it flooded alot, wich i know savages due. Now i can pull on the pull start until my arm falls off without building alot of compression. pull start never hard like when compression builds.

Piston moves freely. not seized or anything.

well thanks for the advice and keep it comming please I'm probably off to the LHS tomorrow.

MeYHymN

If your fuel system is in check and airtight (if your primer is only gettn fuel halfway up the line you got a leak somewhere) you may be having an airleak at the carb. If your engine is running cool and then it dies when it's up to operating temp you may have a worn out sleeve/piston. GL with that.

cemeb4dk

How would i have an air leak at my carb?

MeYHymN

Air could be getting in at the base of the carb where it meets the motor bypassing the needles therefore leaning out the mixture excessively, or the o-rings on your needles could be bad. These are just ideas, but it sounds as if you've got an airleak either in the tank or your fuelline or maybe the primer. With the leak, not enough pressure is exherted on the fuel and that's why it's only reaching up the line half-way. You can take your tank off the truck and put it in the bottom of a water-filled bowl. Put your thumb on the fuel line and blow in the scavenge line and see if you got any bubbles. If your lines and your tank pass this test look for air leaks on the carb.

cemeb4dk

Thanks give it a try.

at this point i'll try anything....

badboy2

My Feedback: (13)

i am having same problem mine is hard to start after it turns of manually or by it self(after finishing the tank) what do i need to adjust..i had this truck for just 2 weeks..and so far this the only problem i had ..but this kind of problem sucks..its better to break something rather than havin this

littlepiston

My Feedback: (12)

take the high end needle out /off and check for stuff in there hell take the hole carb off and clean it out I MEAN COMPLETELY OFF TAKE IT ALL APART AND CHECK FOR ANY DE-BREE

dainjarouz

sometimes..esp. with the 21 bb carb, the fuel gets too hot and doesnt allow the engine to start until its cooled down. thats why high end engines have composite carbs, they dont have the super heated fuel problem.

someone else that knows about this wanna post? i dont know specifically why or how it happens, but i think that might be the prob.

Isphius

My Feedback: (1)

well in full size cars the intake manifold can heat the carb and make the gas boil, this may be the same for the savage. But then all the 21bb motors would do this, not just some. Try sealing the carb/engine mating surface with gasket sealer. and mount the fuel tank higher than it is, if its possible. I know my friends dirtbike does something like that, but it starts revving and then quits when its hot, ill ask him about that.

Unstable

its called hydrolock.

then fuel hits the metal of the carb and vaporises, the pressure pushes the fuel back down the tube, no fuel to the engine.

sounds like its running lean if its getting that hot , I had that happen to me once but the engine was sizzling hot.

clean out the carb and flush the fuel system a bit of debris could have got in and can be leaning you out during the run.

Avalanche

Nope, its "vapor lock" Basicy its when the fuel "vaporizes" instead of "atomizes" In order for fuel to burn well it nees to remain in its original state but finely atomized. When it vaporizes it changes to a sort of fuel "steam" and is way to lean to burn. I would bet $100 that you are too lean, to hot and or your fuel line is right up against the base of the head. If not, your fuel primer has a leak, inwhich case get a new tank. Do you have a temp gun? How hot is it when it stalls? Hydro lock is when the cylinder fills with raw unburnt fuel, since liquids dont compress the cylinder becomes locked hence "Hydro lock"

Unstable

vaporlock, hydrolock, whatever they both make starting a pain.

sorry posted too early in the morning and my brain wasnt in gear yet.

Justintoxicated

So you can start your truck with less than 1/2 a tank after it cools?

If not then i doubt hydro lock is the problem, (BTW I know nothing about RC cars but it would only make sense)

cemeb4dk

The fuel tank is fine, i submerged it in water held my thumb over the fuel line and blew into the exhaust line and no air, so my tank is sealing with no leaks. i reset the carb to factory settings going out now and see how many blisters i can get or maybe throw my should out completely.

will keep posting. please keep ideas comming.

Fast Guy

We are having the same problem with ours. We have to make the carb very rich so when we get below 1/2 a tank it's not too lean. If we adjust the carb to run well with a full tank and when it gets bellow 1/2 it runs way too hot and stalls. The fuel in the carb and line just boils back toward the tank and it won't restart until it cools a while. Running the carb so rich makes it very easy to flood when when starting cold. Sometimes we have to disconnect the pressure line to get it to start cold. Always takes about 20 pulls. If I adjust for proper running with a full tank it is easy to start the next time when cold. The last while we have been refueling when we get down to 1/2 tank as a work around. I'm starting to think we should have waited for the Monster GT.

remten2001

I think its an engine issue the piston and sleeve might be deffective from factory and beleive me it happens...

I am a lucky savage owner that don't have those problems...I even cracked my fuel tank at one time and fixed it with NHP ca glue.....Mine runs the same from the beginning of the tank till the end of the tank....

Make sure your carb is seal and that the hex bolt on the side is tight...and make sure the back plate of the engine is seal and tight as well....

Those are all little things i had to do on mine....