Kraton hello I need help please!

[sipes190]

Hello I’m really new to hobby style rc I bought an Arrma kraton 6s (used) the front wheel drive did not work the guy told me I need the bearing that goes on the outside of the front differential I bought the bearing put it in and put everything back together and the car was working perfectly fine while it was in rear wheel drive but now the front wheels lock after about a full rotation and it can be forced past the stopping point but makes a bad click/grinding sound and it’s only the front that lock up I have taken the front diff apart and it seems fine I put new diff fluid and closed it up making sure not to tighten the top down too tight so it doesn’t spin and it spins perfectly by hand when I have the front diff out but I throw it in the car and it starts locking up please help I can post a video if anyone needs it to diagnose anyone please

 

[Tex Koder]

Hello I’m really new to hobby style rc I bought an Arrma kraton 6s (used) the front wheel drive did not work the guy told me I need the bearing that goes on the outside of the front differential I bought the bearing put it in and put everything back together and the car was working perfectly fine while it was in rear wheel drive but now the front wheels lock after about a full rotation and it can be forced past the stopping point but makes a bad click/grinding sound and it’s only the front that lock up I have taken the front diff apart and it seems fine I put new diff fluid and closed it up making sure not to tighten the top down too tight so it doesn’t spin and it spins perfectly by hand when I have the front diff out but I throw it in the car and it starts locking up please help I can post a video if anyone needs it to diagnose anyone please

Let's see the video..

 

[sipes190]

Let's see the video..

Ok I’m new to the arrma forums I took a video and have it saved how do I put it on here

Here is the video of the wheels locking and agin never did this when it was in rear wheel drive just did it when I put the front drive shaft and bearing in

 

[joshludden]

Ok I’m new to the arrma forums I took a video and have it saved how do I put it on here

Here is the video of the wheels locking and agin never did this when it was in rear wheel drive just did it when I put the front drive shaft and bearing in

Something is binding, maybe check how you put front diff inside the case. It should be on the left side?

 

[sipes190]

Something is binding, maybe check how you put front diff inside the case. It should be on the left side?

Just took the cover off and it is on the left side just like how it’s supposed to be

 

[joshludden]

Just took the cover off and it is on the left side just like how it’s supposed to be

View attachment 354722

Does everything still spin freely?

 

[sipes190]

Does everything still spin freely?

It binds up like in the video but when I take the front differential out and just spin it by hand it does spin with resistance because of the new 50k silicone diff oil yes I can spin it but right when it goes into the car it starts binding is it maybe the diff housing cover am I maybe tightening it too tight and it’s binding on the gears I have no idea

 

[RC Steve]

My recommendation is to pull it apart and clean everything spotless clean. It sounds like you have something stuck in between your gear teeth. Also clean the inside of the gearbox the best you can. If nothing else you can see what condition everything is in. I also recommend you remove your center diff to make sure it's really your front diff that's the problem.

 

[joshludden]

My recommendation is to pull it apart and clean everything spotless clean. It sounds like you have something stuck in between your gear teeth. Also clean the inside of the gearbox the best you can. If nothing else you can see what condition everything is in. I also recommend you remove your center diff to make sure it's really your front diff that's the problem.

+1

 

[sipes190]

My recommendation is to pull it apart and clean everything spotless clean. It sounds like you have something stuck in between your gear teeth. Also clean the inside of the gearbox the best you can. If nothing else you can see what condition everything is in. I also recommend you remove your center diff to make sure it's really your front diff that's the problem.

Ok I will remove the center and see if the front is still binding

 

[sipes190]

My recommendation is to pull it apart and clean everything spotless clean. It sounds like you have something stuck in between your gear teeth. Also clean the inside of the gearbox the best you can. If nothing else you can see what condition everything is in. I also recommend you remove your center diff to make sure it's really your front diff that's the problem.

Ok Steve I have pulled the center diff out and tried rolling it the front indeed is still getting locked up and a certain spot

 

[sipes190]

So I should now take the front diff apart and clean the housing and inside of the diff case and everything

 

[RC Steve]

It's a short list at this point.

Something stuck in between your gear teeth.
A deformed gear tooth.
Mismatched EXB/BLX ring/input gear.
And my favorit, you got a stick stuck in one of your wheels.
This is rare but does happen, a dogbone cross pin has loosened up and is off center and making contact with one of your a-arms.

I can't think of anything else it could be.

 

[JLspeeddragon]

I have to agree with @RC Steve , I think you might have maybe a ball bearing in between the teeth or possibly deformed.. check the small pinion gear, bearings, etc.. there is something that is jamming it up bad..

 

[parcou]

@sipes190

All good advice above, and I, too, would start with all 3 diffs. It's classic for me. My wheel bearings always lock the inner bearing first. I check and change if needed 3-4 runs esp if they sound crunchy.

I'm just saying that as you are checking it, do not overlook the wheel hub bearings. Certainly, I would be into all 3-diffs to get my comfort level.

 

[sipes190]

+1

I finished pulling the front apart took each gear apart and found out after cleaning all the diff fluid off that there was a single tooth that was missing from one of the sun gears in the diff I really appreciate the advice everyone has given me to help me figure the problem out and gain more knowledge about the car here’s the picture of what was broken if anyone was interested in seeing it

@sipes190

All good advice above, and I, too, would start with all 3 diffs. It's classic for me. My wheel bearings always lock the inner bearing first. I check and change if needed 3-4 runs esp if they sound crunchy.

I'm just saying that as you are checking it, do not overlook the wheel hub bearings. Certainly, I would be into all 3-diffs to get my comfort level.

Thank you for that info and you were right mostly I had a broken tooth on one of the diff gears and I also did find a bearing in side of the diff case so thank you for helping me I thought I was never going to figure it out

 

[Garcbomber]

Broken cast teeth will wreak havoc quickly.

Upgrade to machined/hardened if you’re landing on power often

 

[sipes190]

Broken cast teeth will wreak havoc quickly.

Upgrade to machined/hardened if you’re landing on power often

Funny thing is I bought it used and never used the front wheel drive till now old owner broke it and never told me but it’s ok I got it fixed and yeah I will be looking into stronger gears

 

[parcou]

Funny thing is I bought it used and never used the front wheel drive till now old owner broke it and never told me but it’s ok I got it fixed and yeah I will be looking into stronger gears

I'm not sure how comfortable you are with shimming; make sure your input gear mesh well with the outer ring/crown gear. Of course, the inner spider gears in the diff... I'm a nutball on shimming

 

[sipes190]

Anyone know what this part is called I got it when I bought the car and I have no clue I’m guessing it’s a long pin for something because it has that flat top and a hole on the other end but I don’t know where it would go on the car