under powered and over heating issue.

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Harrington81

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Hello there.I'm having a major over heating issue.I know how to tune the engine properly .I first started with turning the HSN 1/8 but it boggs off the line and is not that fast.Then i raced it around for about 20 minutes and the temp was around 255F or more.Then i backed it off a 1/8 to richen it up till it was around the factory setting and it still ran about 250 to 270f.I know it's not sopposed to run this hot.It also boggs of the line and is under powered even when the HSN is turned in about 1 to 1 and half from flush.There must be a air leak somewhere in the engine.Can anyone help.
 
You may need to try the low speed needle. Do the pinch test. Get the engine up to about 200. Pinch the fuel line close to the carb. If the engine dies right away it is too lean, if it runs for awhile you are too fat. It should start to rev up and then die after a second or 2.
 
Hi there. Ya i adjusted the LSN so it's about 1 and a half turns from flush with good results off the line but it still burns way to hot,about 250 to 260F.Theres gotta be a problem with the engine.
 
Not necessarily. Some motors just like to run hotter than others. Are you maybe running a hot plug in hot weather? That will run your temp up also. If it had air leaks the engine would not hold a tune. I just had that problem yesterday. My exhaust gasket had crapped out on me and I didn't even notice it. So mean time I am twisting all the needles trying to get it dialed back in. All I did was get it way out of whack. Replaced the gasket and reset the needles to factory and went from there.
 
um i don't know.When i bought the car and tuned it right it ran great and the temp stayed around 220F it was perfect.It pulled wheelies all day.Now it won't pull wheelies at all.For some odd reason i turned back all the screws to factory and then i could never get that smame performance back.I've been running the same plug since new but i'll try to run a cooler one next time.The exaust gasket i'll check to.If i keep running the engine it'll just get hotter and hotter if i don't bring the engine to an idile.
 
Remember these steps always. Idle. HSN, LSN, Idle. Follow those steps when tuning. If she's bogging right off the line, richen that LSN just a little. If it's running hot after continous full throttle it might need richened a little.

Something to remember always. I've learned, sometimes a motor will run way to rich, and have an extended period of burning in the chamber, which can actually cause higher heat. Sometimes leaning it out when the motor runs like that, it will actually cool it down. You'll notice a ton by the condition of your plug as well. If it comes out right after a run where it's white, it is usually running too lean, if it's black it's too rich. If it's a goldish color, it's good to go. As has been said in some previous posts though, some motors just run hot. Don't rely on the temps only to tune the engine. Sometimes performance can be a better tuning method.

Take it out, reset the needles to factory. Start tuning from there. Drop the temp gun, get it dialed in where you like it. THEN, and only then, start watching the temps. That's a good method to use.

Most engines run around these ranges, 200F to 260F, but I've heard of people running motors rich and reaching over 300F on occasion. Each motor is different, and sometimes it just depends on the current conditions. Also, if you're running a body, make sure to cut some ventilation holes like the windshield so that motor can breathe. I've seen people run bodies without any ventilation and burn motors up quick. :)
 
mine got a sweet spot around 265 to 275.
try setting it back to factory,turn the low side in a half turn then don't mess with it untill you get the high speed set.after you get the high side set the start on the low side.
this method works best for me
 
tuning.

Thanks for the input.Can the motor be running at 250F when it's really lean at factory settings.
 
It's really wierd but when i lean out the HSN about a full turn it runs not bad but then it gets like 260f.So i'll back if off making it to factory settings and it still has the same power as when i richened it out.Does theat make any sense?lol.I'll try to tune it without the temp gun but i don't wanna burn out my engine.
 
Do not tune it for temps, tune it for performance then check temps. There are a lit of variables which will affect the engine temps like AoD posted. Weather has a big affect when tuning these motors also. When you reset your needles to factory, the motor will run very rich for break in purposes. Get the engine to maintain an idle. You may need to lean the HSN in very small increments to get the engine to idle then start tuning the motor with HSN. Like previously stated, each motor is unique and runs/tunes/temps differently than another exact motor. Keep at it and you will get that baby going
 
alright thanks.Is it normal for a engine to just keep climbing past 260F when running.I'm just woried about blowing the engine so i bring it to an idle when it gets past 250F.I know you mentioned don't tune it with temps.My buddys dosn't get past 225F and he runs his all day.
 
I would get it running good then worry about temperature, have you sealed the motor as you mentioned it was bogging?

One of my buddies had similar problems tunning his used to bog off the line and run hot, he sealed the engine as per the FAQ in here and after that the temps dropped and it ran like a dream.

Anyway good luck,

Gav
 
if your thinking its tuned pretty good but still runs a bit hot as was said check the glow plug and see what one your running and i've heard those nova cooling heads will drop temps alot and they look awsome!! I'm sure someone else can vouch for the nova heads...
 
over heating prob

I read some how to seal it but some of it was just greak to me.Is there anyway if you can take the time and explain some of it.Thanks.
 
engine under powered and over heating.

Hi there.I'm running a cool plug and i just replaced the header gasket but it still runs way to hot like 270F plus and has barelly any throttle response.I tried backing off the HSN to flush and played with the LSN at bit and it still runs at 230F when i'm idieling.I know this is normal but when it's 1/3 of a tank it rips really good but still over heats like crazy.Can u guys help please.
 
Ok here is one thread to check out
https://www.hpisavageforum.com/forums/showthread.php?t=1511

Here is the other
https://www.hpisavageforum.com/forums/showthread.php?t=2572

the first thread may be easier to understand on how to do it. Bsically all you are doing is removing the backplate and carb to seal those little pesky air leaks that drives us crazy. When its properly done, there will be a big difference in your engine performance. When you do this, have the manual with you so you are familiar where the correct screws go and how to reassemble properly, and its a great tool to help you become familiar with your truck. Keep working at it, you will get it!
 
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