Buy or repair?

[Cat]

Hello
First post!

So i recently picked up this Revo 3.3. I had problem with engine right of the box. The problem with engine its an aeroholic (air leak). Through the front bearing and backplate. The engine has 1 quarts through it, i have to run it 7 turn out on HSN in order to get a good temp. I'm thinking of replacing the bearings or buy an OS 21-TM.

In order to replace bearings i need to buy ball bearing extractor and ballbearings, which would cost me about. 110 €
OR
Buy the OS engine + glow plugs that going be more expensive. around 270 €. But i will run better..

 

[Kris407]

Won't Traxxas replace it? they give a lifetime warranty or something like it if i remember correctly and the traxxas 3.3 is the better of the two IMO.

 

[Cat]

Won't Traxxas replace it? they give a lifetime warranty or something like it if i remember correctly and the traxxas 3.3 is the better of the two IMO.

From traxxas..
The only warranty is the 30 day electronic warranty. Unfortunately
there is no warranty covering nitro engines. You are welcome to send
the engine in and our Lab Techs will determine if there was a
manufacturing defect and if it can be handled at no charge. They
will not cover wear and tear, poor tuning, inadequate maintenance,
incorrect fuel, abuse or neglect.

Is it possible to replace the bearings without a tool?

I know that the os 21tm is a bit pricy, but i will be a good engine.

 

[WoodiE]

@Cat the OS 21-TM is a great motor and would be one you'd likely see a nice improvement over the Trx 3.3, but is a bit pricey. That said a good starting place for a leaky engine is the Sealing a Nitro Engine for air leaks post.

 

[Kris407]

Send it to Traxxas before you spend $110-$250. It sounds like a manufacturing defect for sure and i know it sucks to wait but they have the tools to fix it and they have excellent service, plus it's a brand new engine and it's not even broken in yet. I know that fancy OS is tempting and you should get it if you really want it but i think the 3.3 deserves a proper chance. Even if they charge you to fix it i bet it's cheaper than buying that bearing punch.

 

[hotrodrob]

Backplate can be sealed with copper rtv,also the carb,...if has only a quart through it and the front bearing is that bad then it's Deffinetely a defective bearing

 

[Cat]

Gonna seal and replace bearing during this weekend.

 

[hotrodrob]

Incase you haven't ever done one you will need to completely disassemble the engine and put the case in the oven for like 10 mins @300f or so

 

[Cat]

Thx, but i'm aware of this. This is gonna me be me alot of weekend prjoect.

 

[Alexander_0_1]

I've changed the bearings in two axial engine, back when you could still buy them in a hobby shop, I never put either of them in an oven. I just used my hudy bearing tool and a piece of wood, as a soft persuader.

I won't put an engine in my oven, but I'll put one in someone else's.

 

[Greywolf74]

Try sealing the engine like the other have suggested and if you still feel like you need to replace the bearings in teh engine you dont need an expensive bearing removal tool. This video shows you how to do it. Now in the video the guy uses a hotplate which is a lot cheaper than a bearing puller however you dont even need this, I've done it by sticking my engine in the oven at 250F. I use an infrared temp gun to check the temp and whne it reaches about 220F you should be able to just tap the crank case a tad and the inner bearing will just fall right out. the outter one is easy to just push out from the back side with a small wooden dowel or anything that wont damage the bearing. I would highly recommend a heat glove though.

 

[Cat]

Beginner question; Is there any front or back of the rear bearing when it looks like this?

OR

Which side should face the small bearing/carb?

 

[Greywolf74]

I've not changed a lot of bearings so i could be wrong about this but i dont think i am so I'll answer this. The sealed side should face the carb. The open side would face the inside of the engine because it gets lubed from the oil in your fuel. the other side helps keep that oil inside your crankcase.

 

[ninnon]

Beginner question; Is there any front or back of the rear bearing when it looks like this?

OR

Which side should face the small bearing/carb?

The sealed side should face outwards, otherwise there'd be no point in the shield....

 

[Cat]

The sealed side should face outwards, otherwise there'd be no point in the shield....

Thats what i thought. Test run tomorrow.

 

[Rolex]

It all seems logical to me.

 

[ninnon]

Thats what i thought. Test run tomorrow.

sounds good

 

[Cat]

Update: Ok, the front and the rear bearing were changed with no direct success. I sealed the front bearing did a test run today. Still needs to have around 6 turns out of HSN. Atleast it held the tune through the tank. I will use this engine untill its worn out. The probably go for the OS 21.

 

[ninnon]

Update: Ok, the front and the rear bearing were changed with no direct success. I sealed the front bearing did a test run today. Still needs to have around 6 turns out of HSN. Atleast it held the tune through the tank. I will use this engine untill its worn out. The probably go for the OS 21.

sounds good- I always think that if you spend more time messing around with it trying to chase down the problem- it'd be easier to just keep on going and use it till it dies

 

[Rolex]

if you spend more time messing around with it trying to chase down the problem- it'd be easier to just keep on going and use it till it dies

I heard that my girlfriend has said that about me.