Rebuilding My Old Savage 21

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The slipper clutch for all savage trucks are the same. The gears are all the same style with the bearing on the outside. So you can use what size you want. Make sure to adjust the motor so the clutch bell gear mesh is set with a piece of paper with the spur gear. Then tighten motor down again. I think your not setting the gear mesh correct and are stripping the gears out.
 
Yeah that's what it is. We didn't back that nut off after getting it tight.
 
Ok, so new question. Had to get fuel the other day. Didn't want to go to my normal rc shop. Went to another one. Got fuel but it's higher oil content. I only have it in my current savage with the 3.5 and it isn't wanting to run. It had the perfect tune for the regular fuel. But this is purple fuel. I believe 14% oil. And before I was running the blue fuel. 9% oil.

Should I dump it from the tank and run the 12% oil fuel. I really don't want to change the tune. It's been running really well and I don't want to mess with that.
 
switching fuels you will need to re-tune, and typically unless day to day is almost exactly the same ambient temperature and humidity, there are going to need to be slight adjustments.
i would start by richening up the mixture on the HSN about 1/8-1/4 turn, its fine to be a bit rich, but the last thing you want is to be lean. it should only be within a few hours tuning away, or who knows might not actually need tuned, but better safe then sorry. purple fuel and 14% oil I'm guessing VP master basher?
if all else fails to get it to run, richen the LSN and HSN slightly, and slightly open the idle gap and start from there. its pretty handy to keep track by keeping a small notebook, and noting what adjustments you make.
 
Well I didn't want to switch fuels to be honest. I should have just gone to my original fuel of the sidewinder. I'm in AZ. It's maybe 70 during the day. No humidity. And 40's at night. Blue VP fuel has been amazing. Only wish I could pick up the original hpi fuel tank without having to wait on shipping. I've only got a 60cc tank on it right now. So my run time is short. But when it runs it rips.
 
yeah, i try to stay with the same fuel, but sometimes just doesn't happen like that. given in arizona, pretty consistent day to day so probably wouldnt need much adjustment unless you were running during middle of the day and running early in the am when its cooler out.
yeah, still pretty slim pickings on the fuel tanks. id check in often with https://www.hobbyrecreationproducts.com/ for when parts come back in stock, next time I'm at my LHS i can check, i know they have some savage parts.
 
That's where I get my stuff from. And they have been out for over a month. About to dig into rebuilding my original savage since I got the motor shims and metal spur gear. Take off the 47T from the 4.6 Savage put the metal 52T on it. Rebuild the 4.6 motor. And move the 3.5 back to its original home. If that doesn't work out then I have a brand new dynamite 28 ready to go on one of them. I just feel it'll do better on the 4.6 Savage version since it's got upgraded parts from the start when it was made.
 
Ok, so new question. Had to get fuel the other day. Didn't want to go to my normal rc shop. Went to another one. Got fuel but it's higher oil content. I only have it in my current savage with the 3.5 and it isn't wanting to run. It had the perfect tune for the regular fuel. But this is purple fuel. I believe 14% oil. And before I was running the blue fuel. 9% oil.

Should I dump it from the tank and run the 12% oil fuel. I really don't want to change the tune. It's been running really well and I don't want to mess with that.
This is thee problem I identified earlier. What are the settings now when you had it tuned with 9% oil lube. Compared to the factory start settings ?You shouldn't have to touch the low. All that should be adjusted it the idle to keep engine running. More oil lube is only going to change the high needle. Once you starve a engine of oil lube it's conditioned to that and damage can be done. You should have no problem running14% oil lube. Just re set the high and tune again. Adjust the idle up if you have to keep it running.

You need to know where you tune settings are Especially the high. If you are near or past the maximum lean setting Then you're going to have problems. If you are 1/2 way between the factory start setting and max lean setting the better off you are when switching % oil lube.
 
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I'll have to ask my buddy. He watched the guy at the rc shop tune it. I know he put it all the way down on all settings. Then went to factory. Then added just a little to that. That's as much as I know because I haven't touched it since other than an 1/8th turn on the high needle to get the proper smoke out the exhaust.
 
That would be a good sign? With more oil lube you should be able to turn in more 1/8 turn . But it should run with factory setting on the high. It will be rich but run. A good engine will do that.
 
We are also thinking that after a short run at the park yesterday, that the motor might be done and it's time to get the dynamite 28 hooked up. Problem with that is the break in process. It'll be a good learning experience for sure. But may I say I'm not looking forward to it?

I'm almost positive that these 2 Traxxas motors I have won't go into my hpi. Anyways, the reason behind thinking the 3.5 motor is gone is because it doesn't sound like there is good if any compression when trying to start it yesterday after the run in the park. It's more of a plop plop plop sound.
 
This all comes back to oil lube and engine break in. Those Traxxas engines run good on18% oil lube and the high should Not be less than 4-1/4 turns open. As a engine gets older you can run more oil lube if you were running less to start. As for break in just go slow and listen to the engine. Know how far you can turn in the high and stay away from it. Use a Temp gun and watch the temp. It should be 200-235 degrees max.
 
It would be good to start out fresh with a new engine ,I also heard that Dynamite is using a new starter system .is that engine
the new updated version?
Also ,sense you are in Arizona ,how come you dont just order Torcco fuels ,their based in your backyard?
 
Hadn't heard of that fuel. And if I'm running my trucks on a daily or on the weekends with my kids seeing as I'm about to go back to work. I would have to wait for it to get here. It's funny, I've got 15 plus years in customer service and I have patience for years when it comes to that. However for myself, I'm way more of a do it right now rather than wait type. Weird huh?

And no, this dynamite is the pull start that breaks after about 5 times. I have roto starts on the side so long as they match up to it that I'll use if I need to.

We tuned the traxxas motors. We started at factory and only adjusted very little from there. Don't have them running the new fuel yet as we still have some of the original blue fuel left. Might just put the sidewinder fuel in them as a stepping stone to the other. However by the weekend I was planning on just getting the original blue VP fuel. I know it, I know my trucks run great with it. Plus it's going to start getting warmer next month most likely. If it stays colder like I hope it does then I won't worry as much.

Another note on the break in, my buddy who has gotten into this with me he has watched so many videos about breaking in a new motor and maybe it'll go fast but from what he's said it's tedious. But hey, gotta do it if I'm going to have a hobby. Right?
 
Torcco fuel is expensive (FREE SHIPPING ) Yea right Its built in. I plan to run Morgan cool power @store its $22 a gallon for 15%. Working on a deal to get 4 cases. I just can't get any other fuel local. I would have to ship it and the Hazmat charge per case is ridiculous and add shipping on top. Forget it. If it gets worse I will make it! To make it would be $16 a gallon.

Break in in no big deal Just leave the high alone and have fun.
 
I get it sent to my door in Cali from Arizona in about 2 to 3 days ,fast enough!
But I switched to Bones brew ,in which is made from VP products!
 
My trucks seem to really like the VP fuel. And it's reasonable on cost. That's why I was sticking with it.
 
I seriously have to Google me some fuel then. All these names keep coming up. Lol
 
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