Savage X 4.6 RTR break-in

[raymond]

Hello all, newbie here!
I have just bought a Savage X 4.6. Read the manual carefully and started the break-in procedure. I am sad to say that it hasn’t been as smooth as I wanted it.
I put it on a stand and primed the engine. My first silly mistake was inserting the Rotostart wrongly and scratching its shaft a little bit. Instead of having it go above the bumper, stupid me tried inserting it through the hole in the bumper… I can’t believe I didn’t notice earlier.

Anyways, I started it and once started, it idled for a few seconds then started revving up. Wheels started spinning like crazy. Turned it off, turned it back on and set the trim via the transmitter. Wheels no longer spun (this was a big mistake on my part).

While idling, there was smoke coming from the engine area. I honestly DID find it peculiar, but I figured it would be oil from the factory that could have been on the engine (sorry if this sounds stupid). Oh boy, I know the reason behind the smoke now. The spur gear is stripped and there are black plastic bits all over the area. I have already ordered two spur gears just in case I strip another one. Clutch bell gear had tons of melted plastic from the spur, but I cleaned it. Forgetting it's a steel CB, I initially thought it was chewed too.

I have contacted HPI and they have said that it’s normal for the wheels to spin at idle during break-in and that I should let them. I have already meticulously taken apart the truck to remove the engine to check the condition of the clutch. It seems to be fine. I am going to be replacing the Philips screw (the one that goes in the shaft and holds the clutch bell) with a high tensile hex of the same dimensions (obviously).

My question is: Is this what I should really do? It’s not that I don’t trust HPI, but I’d really love to get more details on this. I watched their learning lab video and their Savage’s wheels were not spinning at idle.

I just bought this truck and I am already shelling out cash for replacements. 2/5ths of a tank is all I ran it for. The manual is missing some things, I think it’s outdated….
The instructions for setting the failsafe are wrong, and I would have really loved to know that the wheels should spin at idle, if this is true, of course.

Here is a link to an album of pictures of the disassembly procedure for any who are interested: https://drive.google.com/open?id=1-QG6OcArIl1q74Kt9jIpAHcTZJlVn-GE

Thanks for reading.

 

[InTheZone]

Make sure to adjust your clutch bell / spur gear mesh, but first make sure your clutch bell doesn't move back and forth a lot, you want it to have the slightest amount of play and any tighter might bind it to the crank.

To set gear mesh:

-Take a strip of paper and move it between the clutch bell and spur.

-Now with the engine mount loose slide and hold the engine towards the spur gear.

-You don't need to force the engine onto the spur, just slide it to where it pinches the paper into the teeth and it won't budge anymore. Hold it there and tighten the engine mounts in a cross pattern. Example (upper left first, then lower right, then upper right, then lower left).

-Make sure you have blue threadlock at the tip of every bolt and screw in the engine plate, engine mount (lower and upper), clutch bell screw and the pilot / clutch nut that secures the flywheel.

When done you should be able to gently move the spur gear back and forth and hear the slightest tick. Rotation should be smooth but with a slight tick on initial movement.

Make sure your spur is adjusted as well. You need to tighten down the spur nut all the way and then back it off half a turn. Make sure the transmission spur shaft isn't spinning as you tighten the nut. Adjust this when you're ready to drive, if the truck revs but barely moved you'll need to tighten this nut in small increments. Keep throttle low to mid, nothing crazy until the spur is good otherwise you'll burn pads. If mesh is bad you'll strip gears again.

 

[raymond]

Hello, thanks for the reply.

Sorry, but that is not what I asked. I think I will be able to set the mesh just fine.
What I need to know is if it's normal for the wheels to spin at idle when the truck has its wheels off the ground.
HPI have said it is but I need to be sure.

Thanks again.

 

[mr havoc]

First of all if you bought the truck new i would be asking HPI to supply you a new spur gear as the mesh was clearly out, who knows who's building them at the moment ! if the idle is fairly high the wheels will spin with the truck off the ground, maybe try turning it down or put the truck on the ground, if it moves off at low idle then theres clearly a problem with the clutch.But looking at the pictures it seems fine.

 

[raymond]

First of all if you bought the truck new i would be asking HPI to supply you a new spur gear as the mesh was clearly out, who knows who's building them at the moment ! if the idle is fairly high the wheels will spin with the truck off the ground, maybe try turning it down or put the truck on the ground, if it moves off at low idle then theres clearly a problem with the clutch.But looking at the pictures it seems fine.

Thanks for your reply. Yes, I bought the truck new but as I have said in my original post, upon seeing the wheels spin, I thought it would be a good idea to set the throttle trim, which might have been enough to engage the brakes and cause the CB to chew the spur. That is what HPI themselves are saying. Initially, I thought the mesh was off but I don't think it was the case. They have also said that this is not covered by warranty as the user should check beforehand. This is the biggest load of crap I've heard. Are they expecting me to take the truck apart right out of the box just in case the work in their cheap labor factories was not done properly?

They said that it is normal for the idle to be high from the factory and that eventually, the engine will begin to stall all the time because it is set to be too rich. Again, is this true or...?

 

[Jam Racing 1]

These threads may help clear up some of your confusion......
Please read through them so you can get your rig running better......

https://www.hpisavageforum.com/threads/list-of-useful-nitro-engine-threads.13941/

 

[raymond]

Hello, I have reassembled it and it seems to be running well now apart from the fact it's a little too rich.
One thing I have noticed is that after each tank there's dust under the spur gear (which I am assuming is plastic from the spur itself).
I have carefully followed the instructions when I set it. It does not seem like it's getting excessively chewed but it is slightly discolored.
It is worth mentioning that the spur gear itself is not perfect. Unfortunately, it slightly warped and I know this for sure because of 3 things:

-When you turn it you can see that's it doesn't turn perfectly (it kinda wobbles)
-When I set it tight I and rolled the truck, I could notice that at times it was smooth and others it was getting stuck
-When I first started the truck, it started wearing down in some places and in some others not

Before you ask, yes, I did install it correctly paying close attention to back it up a bit once fully tightened.

Is this dust normal? Should there be any? Will it settle after some time or do I need to set it again?

Thanks

 

[Jared]

man it really sounds like your gear ratio for spur gear and clutchbell are off. You have to have that engine secure and the paper test before and after securing the engine mount bolts. You should have NO DUST aka metal shavings from gears grinding ... Maybe adjust your slipper nut also you may just be super tight...

 

[raymond]

man it really sounds like your gear ratio for spur gear and clutchbell are off. You have to have that engine secure and the paper test before and after securing the engine mount bolts. You should have NO DUST aka metal shavings from gears grinding ... Maybe adjust your slipper nut also you may just be super tight...

Thanks for the reply. Slipper nut is ok. I tightened it fully then backed it off half a turn.

There are plastic shavings after each run. Do you think the spur gear might be too loose or too tight?

 

[InTheZone]

Thanks for the reply. Slipper nut is ok. I tightened it fully then backed it off half a turn.

There are plastic shavings after each run. Do you think the spur gear might be too loose or too tight?

Hold the clutch bell in place, do not let it move. Slowly rotate the spur gear back and forth. You should feel the slightest play or hear a very slight tick before the teeth engage.

Go back to my first video for how to set mesh, it's very simple. You know it's too tight when there's no play between the teeth. That is why we use paper to set the mesh because a tad less than no play between teeth should net you the smallest gap and spinning the spur by hand should have minimal resistance.

If you're talking about the spur nut being too loose or too tight here's this. Too loose means your engine revs, engages the clutch bell, but the spur slips (doesn't spin). You need to slowly tighten, I would say 1/4 to 1/2 turn at a time. And do this with the truck on the ground so the weight of the vehicle is against it. Too tight and it'll never slip, putting all the stress on the transmission.

 

[Jam Racing 1]

I have been running my slipper locked down tight and I have not broken anything in my transmission, it will still slip when there is a heavy load such as when it flips and tumbles..... running it loose is going to cause other problems.....

 

[raymond]

I was wrong all this time. What I was seeing is dust from the clutch...
Hpi said it's normal. Spur is fine.