b4 spinning round mid corner

[xray011]

I've ran my b4 with no real problems,that is till i rebiult the diff.
i re done it 4 times now and still have to run it tight to stop the screaming.The last time i did notice that the diff spring is flat(no bounce).
can this cause the screaming?
Also when i turn left the buggy spins on its self but runs wide when i turn right.The left to right turning circle is the same at slow speeds.
So what i am asking is.
will the spring make it sceam?
will the tight diff make the left to right turning different?
or is there some other reason that im missing?
setup is pretty standard
front blue 35w
rear silver 30w
Please help
Alan

[kayce]

If you killed/flattened the spring it obviously needs replacing.
"rebuilding the diff" requires a little more than just relubing it (dead parts need replacing).
I'd also suggest backing off on the slipper, as running it locked puts more strain on the diff.

[carpenterdean]

alan, i would try a new spring first and go from there.

[xray011]

I allready changed the plates and both sets of bearing for ceramics.I just ordered a new rebiuld kit with spring,so i will redo it.
Could the diff effect the steering left to right if it's run to tight?

[adey]

in theory a tighter diff would make the car harder to turn and may cause lack of rear grip in the turn as i understand it. Again, thats how i understand it and i am open to correction.

[kayce]

Originally Posted by xray011

I allready changed the plates and both sets of bearing for ceramics.I just ordered a new rebiuld kit with spring,so i will redo it.
Could the diff effect the steering left to right if it's run to tight?

You can use ceramics for the diff balls, but not in the thrust bearings - THAT's your screaming (well, that and your crushed spring).

[xray011]

Originally Posted by kayce

You can use ceramics for the diff balls, but not in the thrust bearings - THAT's your screaming (well, that and your crushed spring).

Ok well the rebiuld kit has thrust bearings so im just gona replace every thing.
cheers Alan

[xray011]

I have replaced all parts in the diff and its still spinning out on right hand corners.
i also changed the servo just incase.
i did notice that on the bench if i turn left the movement is smooth but when i turn it right it is smooth but flicks the last 10mm of the movement.
i reversed the servo on my transmitter and i still does it on the same side,so its not transmiter setup.
All the turn buckles are the same and the turning circle equal at slow testing.
Could it be the servo arm.(to short or long)?
Im fedup with this now
please help
Alan

[mdb_75]

Is the servo horn set at 90deg/straight up when sat at neutral in the car?

Also when at neutral is the cars steering arm also at 90deg/straight not slightly towards the left or right of the car before you even start to turn?

[blue_pinky]

Check the steering linkage is running smooth and free...and can turn fully each way without restrictions while the servo is powered down.

I wonder if some part of the linkage that moves near the bulkhead might be catching...and popping past an interference once the servo gets the full load on it???

Also, is the servo spaced correctly away from the steering linkage on it's mounts? If it's too close then the end of the steering arm can rub on the front of the servo, and might behave like you've described?

[xray011]

Th e servo horn is at 90deg when wheels are straight,I can not see any binding on the servo.
i will try moving horn one notch right and i will get a offset horn to move the turn buckle more inline with the servo.
cheers guys
Alan

[Pitman Ed]

This is confusing! Firstly you said you were spinning on LH turns, now I think you say RH turns. Anyway, the "flick right" you state that happens on full travel is not good, and suggests you need to reduce the servo travel in that direction. It really sounds as if you have too much RH steering, and too little LH. Slippers do screem on applying punch, especially on high grip surfaces. You could try reducing punch, although if you had way too much it would wheely.

I assume you have replaced the bearings that house the diff outdrives, or confirmed they are free. And be carefull as TA have different sizes that look almost the same but are for different diffs.

[xray011]

well spotted my bad,it spins when turning right.

[xray011]

All sorted, i changed the servo arm for a b4 one and set the servo right back,witch made the turnbuckle on the servo arm straight with the servo.it was angled before and was rubbing on the servo.
ran it last night n im back baby!
cheers for the help guys
Alan