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HPI Savage X4.6 engine issues.

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Old 01-25-2015, 02:04 PM
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linkadrip
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Question HPI Savage X4.6 engine issues.

​Bought a Savage X4.6 back in september. did all the break in procedures ect. truck came new in the box. all excited to play. burned out two one way bearings with the roto start went to the pull start much better. Well when the truck came the engine wouldnt move the flywheel was wrenched on so tight the engine couldn't move. so i had to buy a new flywheel. so that was fixed.. i ran it around the yard for awhile had a little fun. Then the engine starting having its issues.

I can get it to start but it wont stay running.. i give it some gas and it just goes Blahhh and dies.. the high and low speed needles have been set back to factory positions and i have replaced the glow plug. i notice the fuel in the line will siphon back into the tank. So i open the tank lid and close it and that little bit of pressure will push fuel back toward the carb. and i can get it to start. then it will run for a bit and die.

I replaced the stock muffler because it cracked with a new HPI metal one. used on the Savage XL i think. i dont know if this is what is causing my engine issues or not. the engine ran before with it with no problems.

Over the years i have has many rc cars and trucks and never had the issues i am having with this one. my last savage 25, i bought as a roller and bought an sts racing engine for it and it ran like a champ never had these issues.

So is there any advice i can get on what might be the issues with the engine.?

is the engine just a poorly made engine that has issues.

Theres something im not thinking of and i cant figure it out.

Tank seems okay. but i notice when i put my figure over the exhaust and crank it it doesn't seem to pressurize the tank.

But i can pull the line off the muffler and blow into it and the fuel will go to the carb.

Put the glow stick on it and crank it and it fires up and runs for a little bit then just dies or i give it gas an it just goes blahh and dies..



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Old 01-25-2015, 05:22 PM
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Put a 260cc rc airplane fuel tank on it. and got it to run and go pretty good still bogs out and dies. leaned the high speed needle out that seemed to help some. low speed needle is very touchy. leaned it out a little seemed to help some. eventually i'll get the engine issue fixed. seems to be the tank wasn't giving it enough fuel. so it wouldn't run, just bog out at least its running now.
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Old 01-25-2015, 06:03 PM
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Originally Posted by linkadrip View Post
Put a 260cc rc airplane fuel tank on it. and got it to run and go pretty good still bogs out and dies. leaned the high speed needle out that seemed to help some. low speed needle is very touchy. leaned it out a little seemed to help some. eventually i'll get the engine issue fixed. seems to be the tank wasn't giving it enough fuel. so it wouldn't run, just bog out at least its running now.
It sounds like some kind of air leak...It was probably the tank.However,other things can cause it.
Like carb air leak,dirty needles.Loose head.
But does sound like you needed to adjust the tune from a rich setting,that will strain the starter.
Most engines now have 3 needle carb.s with a mid needle,so dont confuse the mid needle with low like
I did one time.I fragged a brand new 8.0 engine that way by a hydrualic lock with a drill start because
I thougt the mid needle was the low.I forgot to set my needles back after finding out that it was a clogged
fuel tank...
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Old 01-25-2015, 06:58 PM
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Yes your right. it has three screws on the carb. one is the idle stop screw. and the low speed screw witch is super sensitive. and the high speed main screw. i got it to scream around the yard pretty good after installing the new tank. but it still bogs on acceleration. slight bogging then it catches up and goes like a banshee across the yard.. it will go good for a little bit then i'll accelerate and it will just Blahhhh and die.. I broke the engine in like the HPI video said in the begining. and it was going good. then i guess that tank just quit working. it has that o ring on the lid. maybe thats it.

Problem i can see with that tank its theres no way to take the pick up out of it and clean it if it is clogged just buy a new tank. they sure do know how to make money. build a tank that isn't serviceable.

Im going to pull the engine and check it. make sure there aren't any air leaks. it is possible that is the problem that is why i cant get a good tune on it. seems to run fine and go great until it gets hot then it. just bogs out and dies. and is hard to start. must be expanding and letting in air somewhere. possibly..
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Old 01-25-2015, 07:44 PM
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Originally Posted by linkadrip View Post


Yes your right. it has three screws on the carb. one is the idle stop screw. and the low speed screw witch is super sensitive. and the high speed main screw. i got it to scream around the yard pretty good after installing the new tank. but it still bogs on acceleration. slight bogging then it catches up and goes like a banshee across the yard.. it will go good for a little bit then i'll accelerate and it will just Blahhhh and die.. I broke the engine in like the HPI video said in the begining. and it was going good. then i guess that tank just quit working. it has that o ring on the lid. maybe thats it.

Problem i can see with that tank its theres no way to take the pick up out of it and clean it if it is clogged just buy a new tank. they sure do know how to make money. build a tank that isn't serviceable.

Im going to pull the engine and check it. make sure there aren't any air leaks. it is possible that is the problem that is why i cant get a good tune on it. seems to run fine and go great until it gets hot then it. just bogs out and dies. and is hard to start. must be expanding and letting in air somewhere. possibly..
Yea,I know what you mean with the tanks..Ive modded acouple of mine,an did away with the internal filter.
I use hot soapy water to clean them,an use back pressure to flush the filter.
Some brands sell tank rebuild kits.
I wish that I had a smaller fuel economy car,I would drive up there an we can tune an bash...
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