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Break in problem

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Maddogjez

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Hi guys, I've searched around the forum and cannot find a good solution to my problem, so sorry for asking what has probably been asked a million times.

I'm trying to run in my Savage x ss, i can start it up ok and drive very slowly, but when i give it the slightest bit of throttle the engine lowers in revs and dies, i cannot reach half throttle without the engine cutting out. Also, not sure how this happend but i just found a hole at the top of the fuel tank, the pullstarter snaps back sometimes when the engine dies and the handle probably smashed the tank, i tried sealing the hole with a coin and bluetack/tape and drove the car around but still experiancing the same problem, maybe that is what the problem is? or could it be a clutch problem? or maybe to lean? :S
 
That hole on the fuel tank, are you taking about the one that goes to the pipe? That is the pressure line. The one on the bottom is the on that goes to your carburetor inlet nipple. If you are talking about a new hole, than I suggest replacing it with a primerless tank from HPI. Less hassle about leaks.

Are you breaking this engine in? How many tanks have been run? Your symptoms scream air leak. Do a search here for "air leaks" to help you find articles about "how to seal an engine?".

Let us know more so we can better assist you.
 
Ok thanks, yes I'm breaking the engine in, it has had almost 4 tanks of fuel so far. The hole in the tank is a new hole that shouldnt be there, i think the pull starter handle made the hole:( And as far as i know it is a primerless tank, i just have to cover the exhaust and pull the starter a few times to prime.
 
If you have the hole as you say, stop running it and get a new tank. Running with a damaged tank will make your break in difficult. Break in is already difficult as it is.
 
You definately need to replace the tank. These setups are pressurized through the nipple on the pipe, and without the proper pressure, you're not getting the proper fuel/air mix.
This is also the break in period. Take your time and do it right.
 
Ok thanks guys, ill get a new tank asap and see if that helps. If i can seal the hole on the tank would it be ok to try give it a run tomorrow to see if it helps?
 
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I would go ahead and get the new tank. You could never be absolutely sure that it is sealed if you try to repair it. That way you could rule out the tank for sure.
 
I recommend against that. No telling what the sealant will do to the fuel or how well the seal will work. A new one is alike 9 bucks.
 
I haven't found a seal that both sticks to tank plastic and doesn't dissolve in the fuel yet. I've tried a lot of stuff... About all I know that works (in a pinch) is melting another piece of fuel tank type plastic over the hole with a soldering iron. So, when you get your new tank, don't throw away your old one. You might be able to salvage pieces to patch a hole later on.
 
Ok thanks everyone, ill let you know if a new tank sorts the problem. unfortunatly a new tank over here in the UK is like £15, which is about $25, so gonna be a couple days before i can get one:(
 
Olds is right. You definately want to save the tank, especially the lid. Seal went bad in mine and had the old one laying around so I used that and it works fine.
 
Well, i sealed the hole pretty nicely with a bit of plastic covering it, held down and sealed with bluetack, theres no way the sealant can get into the tank and it seems pretty good so far. took it for another test run today, did a bit of tuning, and got it to accelerate very nicely, and top speed slightly increased and also it does not stall when accelerating hard, so a big improvment from yesturdays run. However, when i punch the throttle the engine bogs down and almost fails, so i cannot get any speed out of it. Could this be an air leak problem still?
Also, been trying to get it to idle without the wheels turning and its very, very close to working but if i lower the idle speed any lower then it stalls, maybe this is a clutch problem?
 
You shouldn't be concerned with how it behaves when you punch it, since you're still in the break in period. As it breaks in, it will need some tweeking, and then can be tuned for performance.
 
As rolex suggests, don't worry over the rough tune right now. Once you get 7-10 tanks through it, you can lean it more and get performance out of it. After engines break in, the tend to settle down a bit. By that I mean they tend to start easier, idle better, hold a tune better, wrap through the RPM's cleanly...

With only a few tanks through it, it's not to that point of good running yet. The name of the game during break in is temp, get it up to 210F and keep it there.
 
Thanks for your help everyone, unfortunatly my savage is still not working,, I've been trying differant needle settings and it just wont get any speed, it doesn't change into second gear also. I have not tried to seal any air leaks yet, i think i might have to try that?. But the slipper clutch kept coming loose today, even after tightening it, it still acts strange,,, it sounds like it is slipping although it is pretty tight on, I've no idea what is wrong. Could it be the idle setting on the engine that causes wierd clutch issues? i can't get it to idle properly at all, the wheels always turn a little bit.
 
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How many tanks through it so far? What percent oil/nitro are you running? What are your temps at the glow plug?

I test my slipper by holding the truck stationary, typically I step on the roll bar and hold it down. Then I peg the throttle. If it revs and slips right away, I tighten it. If it takes a bit before slipping, then I typically let it be. By holding it stationary with the body off, you can see the spur. If it spins, it's slipping or something else is slipping. Since it's new, I'd say the slipper would be slipping if the spur turns.
 
just over half a gallon now. running 30% nitro fuel. I dont know the temps because i dont have a temp reader, but it seems to get pretty hot at times. I'm starting to think the transmission box is dodgy:S think I'm gonna have to resort to my LHS and see what they say:(
 
Actually,, i tightend the slipper last night and also moved the engine slightly to get a closer mesh between the slipper and clutch. I've just come back from the best run I've had yet, it all seemed fine, was getting some nice acceleration/speed from it, although I'm still not sure about second gear, i cannot hear it change. The only problem that still stands is the iratic idling, when the truck rolls forward (without throttle) the clutch sounds mental, like its slipping loads, but as soon as i accelerate it seems fine, it does this after I've been running the truck for about 10-15 mins and it seems like its heat causing the issue. And also, was just priming the engine and the pull starter is stuck, it wont go back in:S

Apart from these 2 problems i think its pretty much 90% running fine
 
Maddogjez said:
Actually,, i tightend the slipper last night and also moved the engine slightly to get a closer mesh between the slipper and clutch. I've just come back from the best run I've had yet, it all seemed fine, was getting some nice acceleration/speed from it, although I'm still not sure about second gear, i cannot hear it change. The only problem that still stands is the iratic idling, when the truck rolls forward (without throttle) the clutch sounds mental, like its slipping loads, but as soon as i accelerate it seems fine, it does this after I've been running the truck for about 10-15 mins and it seems like its heat causing the issue. And also, was just priming the engine and the pull starter is stuck, it wont go back in:S

Apart from these 2 problems i think its pretty much 90% running fine
Click to expand...


One big problem I had with my savage X during break in was the idleing. The thing would never idle without the wheels turning, and I lowered the idle so far that the thing would always stall. I chased the problem to the flywheel. The clutch pins on the flywheel were coming loose and making thier way out of the flywheel as far as the clutch bell. Then they would rub on the clutch bell basically holding the clutch back from turning. In chasing this problem I managed to strip out the bevel gears and ruin one clutch bell. So I contacted HPI about the problem and within 5 days thier was a new clutch bell, flywheel and differential assembly at my door....no charge!! thats what I call service.

anyway may want to look into your clutch, take the engine out and take the clutch bell off and check things out in there.

Good luck
 

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