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Carb. tuning??????????? hpi 21 savage

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M

mark b

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I found a savage 21 at the thrift store for $15 . It looks like it was never driven. I try to start it but it runs wide open with carb slide closed. moving linkage by hand doesn't effect it then it shuts down. I tried to reset the needles to factory but every time I tighten the low speed needle the mid range needle unscrews. also when I prime the fuel tank I am unable to get all the air bubbles out due to backflow.
Thanks Mark
 
WOW, that's some deal. It's quite obvious you have a major air leak. Start by replacing all your fuel and return lines. Install a filter, then let us know what it does when you start it. We'll help you get it running.
 
The lines appear ok. is it normal for the low needle to turn while I adjust the mid range needle and vice versa. I am unable to achieve factory settings.What about the back flow of fuel to tank from carb.
Thanks Mark
 
For what you paid for a Savage, don't skimp on something that's only a buck a foot. It may LOOK fine, but it might be leaking around the fittings. You could also have a leak in the fuel tank cap seal.
Again, for what you paid for it, you'd still be WAY ahead if you avoided the headaches and got a new carb.
 
Those lines are more than likely porous from sitting around for so long. You definitely have air leaks so you really need to find them and fix them.

I don't understand how you can have "backflow" from the carb to the tank unless you have something plumbed wrong. The pressure from the exhaust is what forces fuel into the carb not vice versa. Please explain! The "bubbles" are not a symptom of "backflow" they are caused by an airleak.
 
I will put new lines on tomorrow. When I pump the fuel tank with the primer the fuel goes up the line a little and then flows back a little so that I am unable to get all of the air out of fuel line. What about my needle predicament? I could easily afford to buy a new carb. But what is the challenge in that? I will get this car to run. Thank You for helping me!
Mark
 
Here's the motor
 

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NICE!!! $15 for a Savage...WOW!!!

Ya replace all fuel lines, maybe check the o-ring on the cap of the fuel tank to see if its not damaged or missing. Got any pics of the whole truck? Wanna see what that $15 Savage looks like...Congrats for that score.
 
mark b said:
I found a savage 21 at the thrift store for $15 . It looks like it was never driven. I try to start it but it runs wide open with carb slide closed. moving linkage by hand doesn't effect it then it shuts down. I tried to reset the needles to factory but every time I tighten the low speed needle the mid range needle unscrews. also when I prime the fuel tank I am unable to get all the air bubbles out due to backflow.
Thanks Mark
Click to expand...

If your tank has a primer on it, ditch it and get the updated primerless tank. Just one less HUGE airleak to contend with.
 
It does have the primer. Silicone it up or swap to the newer tank. That is a heck of a find!
 
Scrogg said:
It does have the primer. Silicone it up or swap to the newer tank. That is a heck of a find!
Click to expand...

Actually silicon sealers will be eaten away by nitro fuel. You can remove the primer and seal the hole with JB Weld.

mark b said:
I will put new lines on tomorrow. When I pump the fuel tank with the primer the fuel goes up the line a little and then flows back a little so that I am unable to get all of the air out of fuel line. What about my needle predicament? I could easily afford to buy a new carb. But what is the challenge in that? I will get this car to run. Thank You for helping me!
Mark
Click to expand...

Find and fix all the air leaks first then you can work on the needle situation if it persists.
Like others have said--get rid of that primer button!
 
Thank guys!!! I will replace lines, add filter, and dump the primer. Then I will see if I can get the needles sorted out and fire this thing up.

Here's some other pictures, They wanted $25 for this thing but I told them that was too much, But Lets see what the bottom line is when I actually get this truck to drive.

Mark
 

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Looking at the pics, it's worth an easy 150 bucks.
Just buy the newer tank of an X model Savage. It has an internal filter. External fuel filters are just another place to leak.
 
SHE RUNS!!!!!!! LIKE A SCREAMING BANSHEEE!!!!!
My neighbors are now giving me dirty looks.
I did all suggestions and reset carb. I think my major prob. was the low speed needle, it threads all the way through the slide and was hard for me to find the closed position so that I would have a starting position from which to back it off, but all is good, just need a little fine tuning.
Thanks to all!!!!!!!!!!!!!!
Mark
 
Cool, those HPi .21's are quicker than most people think. I was shocked seeing a truck like yours' in action for the first time.
 
Thanks! we'll see how it looks after my kids get their turns. Once they figure out how to be proficient with the remote I'll probably pull my planes out of the attic. I've never flown an rc plane before, but I was cleaning out a clients garage and he paid me to dump 3 complete planes and several large boxes of rc stuff - servos,controllers,motors,props and such. I just threw it all in the attic and haven't touched it since.
Thanks again, Mark
 

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